Release notes
*************

This file describes changes in recent versions of Modules. It
primarily documents those changes that are of interest to users and
admins.


Modules 5.2.0 (2022-11-08)
==========================

* Introduce the "--optional" option on "prereq", "prereq-all",
  "depends-on" and "always-load" modulefile commands. Expressed
  optional dependency is considered satisfied even if modulefile is
  not loaded. If optional requirement is loaded afterward, dependent
  module is automatically reloaded, unless if the "auto_handling"
  configuration option is disabled.

* A dependency expressed in modulefile with "module try-load" command
  is considered optional. Dependent module is automatically reloaded
  if the optional requirement is loaded afterward, unless if the
  "auto_handling" configuration option is disabled.

* Raise error in case of unknown or misplaced option set on "prereq",
  "prereq-all", "depends-on" or "always-load" modulefile commands.

* Add the "--timer" command-line switch to report the total execution
  time of the **module** command. Also report the execution time of
  every internal procedure calls when mixed with "--debug" option.

* Init: move "PATH" setup (to locate Modules' binaries location) from
  shell initialization scripts to the "autoinit" sub-command. (fix
  issue #462)

* Init: move "MANPATH" setup (to locate Modules' man-pages) from shell
  initialization scripts to the "autoinit" sub-command. (fix issue
  #462)

* Init: move shell completion setup from shell initialization scripts
  to the "autoinit" sub-command. (fix issue #462)

* Enclose installation path references in shell code produced by
  "autoinit", in initialization scripts and Makefiles to guaranty
  correct evaluation in case these paths contain a space character.
  Note that the quarantine mechanism is not compatible with such
  installation paths.

* Fix "source-sh" and "sh-to-mod" when used with *fish* shell script
  if "regex-easyesc" fish option is enabled. (fix issue #463)

* Add the "protected_envvars" configuration option to define a list of
  environment variables that cannot be modified by modulefile
  commands. When set, "protected_envvars" defines
  "MODULES_PROTECTED_ENVVARS" environment variable. (fix issue #429
  with contribution from Adrien Cotte)

* Introduce the "lint" sub-command to statically analyze syntax of
  modulefiles, modulerc and global/user rc. (fix issue #451)

* Add the "tcl_linter" configuration option to define the program used
  to analyze files with "lint" sub-command. This option is set to
  "nagelfar.tcl" by default. When changed from default value, the
  "MODULES_TCL_LINTER" environment variable is defined. Default value
  can be changed with "--with-tcl-linter" and "--with-tcl-linter-opts"
  installation options.

* Add the "--enable-nagelfar-addons" installation option (enabled by
  default) to install specific syntax databases and plugins to lint
  modulefiles, modulerc and global/user rc with Nagelfar. These files
  are installed in the directory designated by the "--nagelfardatadir"
  ("DATAROOTDIR/nagelfar" by default).

* Doc: add lint sub-command design notes.

* Install: use **install** command rather **cp** or **mkdir** to
  install Modules and guaranty consistent permission modes on deployed
  files.

* Also unset "pushenv" value stacks on "clear" sub-command.

* Doc: add mod-to-sh sub-command design notes.

* Introduce the "mod-to-sh" sub-command to translate designated
  modulefile(s) into code for specified shell. (fix issue #447)

* Make "source" sub-command accepts modulefile specification as
  argument. If argument does not correspond to a file path, search it
  among available modulefiles. (fix issue #424)

* Doc: clarify "set-alias" only define shell alias and not shell
  function.

* Add the ability to filter the list of collections returned by
  "savelist" sub-command. Filtering pattern is matched in a case
  insensitive manner by default.

* Add support for "--starts-with" and "--contains" options on
  "savelist" sub-command.

* Highlight all search patterns on "list" sub-command output instead
  of only the first one..

* Highlight all search patterns on "savelist" sub-command output.

* Add support for "--all" option on "savelist" sub-command not to
  limit result to the collection matching currently defined
  "collection_target".

* Doc: add Shell support section in modulefile man page to describe
  how shells support the different kind of environment changes that
  can be defined in modulefiles.

* Record during "autoinit" sub-command the initial environment state
  in "__MODULES_LMINIT". Enabled modulepaths and loaded modulefiles
  through "modulespath" and "initrc" initialization configuration
  files are recorded in this new environment variable.

* Add "reset" sub-command to restore initial environment. It takes
  recorded environment in "__MODULES_LMINIT" and restores it.

* Initial environment is restored when collection name specified on
  "restore" sub-command equals "__init__".

* When no argument is provided to "restore" sub-command and if
  *default* collection does not exist, initial environment is
  restored.

* Initial environment content is displayed when collection name
  specified on "saveshow" sub-command equals "__init__".

* When no argument is provided to "saveshow" sub-command and if
  *default* collection does not exist, initial environment content is
  displayed.

* Add "reset_target_state" configuration option to determine behavior
  of "reset" sub-command. When set to "__init__" (default value)
  initial environment is restored. When set to "__purge__", a "purge"
  sub-command is performed. Any other value, corresponds to the name
  of a collection to "restore". When set, "reset_target_state" defines
  "MODULES_RESET_TARGET_STATE" environment variable.

* Doc: add Initial environment design notes.

* Unload *sticky* modules on "restore" and "reset" sub-commands to
  fully set environment in collection or initial state.

* Testsuite: add *lint* testsuite to validate syntax of shell and Tcl
  scripts of this project. This testsuite can be invoked with "make
  testlint" or "script/mt lint". sh, bash and ksh scripts are checked
  with ShellCheck tool and tcl scripts are checked with Nagelfar.

* Update "modulecmd.tcl" code and add Nagelfar inline comments to fix
  linter reports.

* Script: add usage message and support for "-h"/"--help" option on
  **mrel**, **mpub**, **mt**, **mtreview**, **nglfar2ccov**, **mb**
  and **mlprof** development utilities.

* Doc: describe **script/mt** and **script/mb** utilities in
  Contributing guide.

* Fix ShellCheck error, warning and info reports over all sh, bash and
  ksh shell scripts. (fix issue #470 with contribution from Lukáš
  Zaoral)

* Init: update profile script for sh-like shells to only source sh or
  bash initialization script when BASH environment variable is found
  set. (fix issue #473)

* Add "stash" sub-command to save current environment and restore
  initial one.

* Add "stashpop" sub-command to restore stash collection then delete
  this collection file.

* Add "stashrm" sub-command to delete stash collection file.

* Add "stashshow" sub-command to display stash collection file.

* Add "stashclear" sub-command to delete all stash collection files.

* Add "stashlist" sub-command to list all stash collection files.

* Update "savelist" sub-command to filter out stash collections unless
  if "--all" option is set.

* Doc: ensure current user environment does not break logging system
  in Log module command recipe. (fix issue #475)

* Rename the default git branch from *master* to *main* to use
  inclusive terminology.

* Mark loaded modules that could benefit from a refresh evaluation in
  the "__MODULES_LMREFRESH" environment variable.

* Optimize "refresh" sub-command to only evaluate loaded modules that
  defines volatile environment changes (shell completion, alias or
  function). (fix issue #477)

* Add "modulefile_extra_cmds" hook variable that could be defined in
  "siteconfig.tcl" file to define specific commands in modulefile
  interpreter context. "modulefile_extra_cmds" is a list of command
  name and relative procedure pairs. (fix issue #286)

* Add "modulefile_extra_vars" hook variable that could be defined in
  "siteconfig.tcl" file to define specific variables in modulefile
  interpreter context. "modulefile_extra_vars" is a list of variable
  name and value pairs. (fix issue #286)

* Add "modulerc_extra_cmds" hook variable that could be defined in
  "siteconfig.tcl" file to define specific commands in modulerc
  interpreter context. "modulerc_extra_cmds" is a list of command name
  and relative procedure pairs. (fix issue #286)

* Add "modulerc_extra_vars" hook variable that could be defined in
  "siteconfig.tcl" file to define specific variables in modulerc
  interpreter context. "modulerc_extra_vars" is a list of variable
  name and value pairs. (fix issue #286)

* Doc: Add Site-specific configuration section in module man page.

* Doc: extend Collections section with examples in module man page.


Modules 5.1.1 (2022-05-31)
==========================

* Install: add **rpmlint** rc configuration file to filter false
  positive warning messages.

* Install: better guess "libdir64" and "libdir32" directory locations
  when "libdir" does not end with *64* but contains *64*.

* Install: update RPM spec file to move libtclenvmodules in an
  environment-modules directory under "libdir".

* Fix rendering of loading or unloading module designation when
  configured color palette does not set the "hi" color key. (fix issue
  #455)

* Remove the *already loaded* message displayed when verbosity level
  is higher or equal to "verbose2" if new tags are applied to the
  loaded module. (fix issue #456)

* Report a global known error when current working directory cannot be
  retrieved due to the removal of this directory. (fix issue #457)

* Update tags set through "prereq" command on all already loaded
  requirements. (fix issue #459)

* Update module designation with the tags set by reloading dependent
  module. (fix issue #460)

* Install: include the "lib/config.guess" and "lib/config.sub" scripts
  in distribution tarball if generated by **autoreconf**.

* Install: call "git" command in "Makefile" only if the definitions of
  "version.inc" need to get built or refreshed.


Modules 5.1.0 (2022-04-30)
==========================

* Allow to declare "variant" with no list of accepted value. Such
  variant accepts any value specified. (fix issue #405)

* Add the "redirect_output" configuration option to control on *sh*,
  *bash*, *ksh*, *zsh* and *fish* shells whether or not the output of
  the **module** function should be redirected from stderr to stdout.
  When set, "redirect_output" defines "MODULES_REDIRECT_OUTPUT"
  environment variable.

* Introduce the "--redirect"/"--no-redirect" command-line switches to
  supersede the value of the "redirect_output" configuration option on
  *sh*, *bash*, *ksh*, *zsh* and *fish* shells. (fix issue #410)

* Add the "--return-value" option to the "getenv" and "getvariant"
  modulefile commands to force to return the value of respectively
  designated environment variable or variant when modulefile is
  evaluated in *display* mode. (fix issue #422)

* Introduce the "state" sub-command to display Modules states.

* Add the "supported_shells" state to get the list of the shells that
  are supported by "modulecmd.tcl" through the "state" sub-command .
  (fix issue #426)

* Filter out the variables intended for Modules private usage when
  processing the environment changes made by a script evaluated by
  "sh-to-mod" sub-command or "source-sh" modulefile command. (fix
  issue #427)

* Doc: add Control mode behaviors design notes.

* Doc: add Add new configuration option design notes.

* Set a Code of conduct for the project and its community based on the
  widely adopted Contributor Covenant.

* Doc: add Add new module sub-command design notes.

* Add the "--remove-on-unload" option to the "remove-path" to also
  remove value when modulefile is unloaded.

* Raise error when an unknown option is set on "module use" or "module
  unuse" modulefile command.

* Rework emitted debug messages to remove obvious ones and
  systematically report each modulefile command processed with their
  arguments.

* Add the "--append-on-unload" option to the "remove-path" and "module
  unuse" modulefile commands to append back when modulefile is
  unloaded the value removed at load time or a specific value set
  after this option.

* Add the "--prepend-on-unload" option to the "remove-path" and
  "module unuse" modulefile commands to prepend back when modulefile
  is unloaded the value removed at load time or a specific value set
  after this option.

* Add the "--noop-on-unload" option to the "unsetenv", "remove-path"
  and "module unuse" modulefile commands to perform no operation when
  modulefile is unloaded.

* Add the "--unset-on-unload" option to the "unsetenv" modulefile
  command to also unset environment variable when modulefile is
  unloaded.

* Add the "--set-if-undef" option to the "setenv" modulefile command
  to set environment variable when modulefile is loaded only this
  variable is not yet defined.

* Install: add the "--with-bashcompletiondir", "--with-
  fishcompletiondir" and "--with-zshcompletiondir" installation
  options to install shell completion scripts in their system-wide
  location. (fix issue #428)

* Doc: add Lmod Tcl modulefile compatibility design notes.

* Introduce the "add-property", "remove-property" and "extensions"
  modulefile commands for compatibility with Lmod Tcl modulefiles.
  These commands are evaluated as a *no-operation* command.

* Introduce the "prereq-any" modulefile command for compatibility with
  Lmod Tcl modulefiles. "prereq-any" is an alias of "prereq" command.

* Produce a clear error message when wrong number of argument is
  received by "prereq" command.

* Doc: describe "ModulesVersion" in *Modules Variables* section in
  modulefile man page.

* Set "ModuleVersion" as an alias over "ModulesVersion" modulefile
  variable for compatibility with Lmod Tcl modulefiles.

* Doc: describe "reportError" and "reportWarning" modulefile commands.

* Add the "require-fullname" modulefile command for compatibility with
  Lmod Tcl modulefiles. This command aborts modulefile *load*
  evaluation if modulefile's name is not fully specified.

* Add the "prereq-all" modulefile command, alias over the "prereq"
  command which acts as an *AND* operation when multiple modulefiles
  are specified.

* Add the "depends-on" modulefile command, alias over the "prereq-all"
  command for compatibility with Lmod Tcl modulefiles.

* Introduce the "keep-loaded" module tag that avoids an auto-loaded
  module to get automatically unloaded when its dependent modules are
  getting unloaded. Update default "tag_abbrev" configuration option
  to add an abbreviation for the new tag ("kL") and default light and
  dark color palettes.

* Add the "always-load" modulefile command for compatibility with Lmod
  Tcl modulefiles. This command loads designated modulefile and
  applies the "keep-loaded" tag to it.

* Add the "load-any" sub-command and "module load-any" modulefile
  command for compatibility with Lmod Tcl modulefiles. This command
  loads one modulefile from specified list.

* Add support for "--not-req" option on "module try-load" and "module
  load-any" modulefile commands.

* Doc: add Module magic cookie check design notes.

* Add the "mcookie_check" configuration option that control whether
  the magic cookie at the start of modulefile (i.e., "#%Module" file
  signature) need to get checked or not. When set to "eval" the number
  of file checks is significantly reduced when walking through
  modulepaths to search for modulefiles. Default value for this option
  is overridden by the "MODULES_MCOOKIE_CHECK" environment variable.

* Doc: describe "puts" Tcl command and its specific feature when used
  in modulefile.

* Create the "prestdout" channel for "puts" modulefile command to be
  able to send content that will be evaluated in current shell session
  prior any other content. (fix issue #432)

* Add the "family" modulefile command for compatibility with Lmod Tcl
  modulefiles. This command defines family name as a module alias over
  currently loading module and express a conflict over this name to
  ensure only one member of a family can be loaded in user
  environment. "family" also defines the "MODULES_FAMILY_<NAME>" and
  "LMOD_FAMILY_<NAME>" environment variables.

* Doc: add Reduce I/O load cookbook recipe.

* Add the ability to filter the list of loaded modules returned by
  "list" sub-command. Filtering pattern could be part of module name,
  symbolic version or alias and is matched in a case insensitive
  manner by default. It could also leverage the Advanced module
  version specifiers syntax.

* Add support for "--starts-with" and "--contains" options on "list"
  sub-command.

* Doc: add Shell completion design notes.

* Introduce "complete" and "uncomplete" modulefile commands to
  respectively enable and disable shell completion for a given command
  name. *bash*, *tcsh* and *fish* shells are supported.

* Track shell completion changes of *bash*, *tcsh* and *fish* shell
  scripts on "sh-to-mod" sub-command and "source-sh" modulefile
  command.

* Fix typos found in code, tests and documentation. (contribution from
  Dimitri Papadopoulos Orfanos)

* Update the "sh-to-mod" and "source-sh" mechanisms to support nested
  function definition on fish shell.

* Fix the "sh-to-mod" and "source-sh" mechanisms to correctly detect
  functions with a "_" character in their name on fish shell.

* Update the **module** shell function definition for sh-kind shell to
  enclose the output generated by "modulecmd.tcl" in quotes in order
  to pass it to the eval command. This change fixes definition of
  shell function, especially when coming from shell script evaluation
  over the "sh-to-mod" and "source-sh" mechanisms. (fix issue #434)

* Fix csh shell alias detection on "sh-to-mod" and "source-sh"
  mechanisms when enclosed in parenthesis. (fix issue #434)

* Include for fish shell environment analysis on "sh-to-mod" and
  "source-sh" mechanisms the private functions defined by evaluated
  script, in order to catch all definitions that may be useful for
  shell completion.

* Fix the "sh-to-mod" and "source-sh" mechanisms to correctly detect
  empty function on fish shell.

* Script: add **pre-commit** git hook script to help verify if commits
  are free of misspellings (with codespell tool) and trailing spaces.

* Doc: fix typos found in documentation with Aspell utility.

* Doc: describe Dependencies between modulefiles in modulefile man
  page. (fix issues #431 and #433)

* Script: update **pre-commit** git hook script to spell check
  documentation files with Aspell tool.

* Script: add **commit-msg** git hook script to spell check commit
  message with Aspell tool.

* Doc: clarify that "#%Module" is a file signature also called Modules
  magic cookie.

* Doc: update the ENVIRONMENT section in module man page to provide
  for each Modules environment variable the name of the configuration
  option that could be used to set the variable with the "config" sub-
  command.

* Doc: clarify in module man page that "MODULES_SET_SHELL_STARTUP",
  "MODULES_SHELLS_WITH_KSH_FPATH" and "MODULES_WA_277" should be set
  prior Modules initialization to get taken into account.

* Doc: update Installing Modules on Unix document to provide the name
  of the configuration option linked the installation options.

* Doc: describe in module man page the default value of each
  configuration option and linked installation option and command-line
  switches.

* Doc: add *Configuration options* section in Installing Modules on
  Unix document with a table summarizing all configuration options and
  their relative installation options and environment variables.

* Add the "pushenv" modulefile command for compatibility with Lmod Tcl
  modulefiles. This command sets designated environment variable with
  specified value and save the previous value set to restore it when
  the modulefile is unloaded. Previous values are saved in a
  "__MODULES_PUSHENV_<VAR>" environment variable.

* Doc: add Compatibility with Lmod Tcl modulefile section in
  modulefile man page.

* Update definition of the "module()" python function and python
  initialization script to explicitly send output to "sys.stderr" to
  get the ability to catch this content.

* Lib: handle "sysconf" error in function implementing the
  "initStateUsergroups" procedure. (contribution from Lukáš Zaoral)

* Introduce the "--tag" option for the "load", "try-load", "load-any",
  "switch" sub-commands and associated "module" modulefile commands
  and "prereq", "prereq-all", "depends-on" and "always-load"
  modulefile commands. This new option applies specified tags to the
  module to load.

* Record tags set to loaded modules with the "--tag" option in the
  "__MODULES_LMEXTRATAG" environment variable to make this information
  persists after module being loaded.

* When saving a collection, record loaded module tags set with the "--
  tag" option and those resulting from module load states (like "auto-
  loaded" and "keep-loaded"). The "--notuasked" string previously used
  to designate auto-loaded modules in collection is changed into the "
  --tag=auto-loaded" option.

* Introduce the "collection_pin_tag" configuration option, that
  records in collection all tags set on loaded modules when enabled.
  Option is disabled by default and when set it defines the
  "MODULES_COLLECTION_PIN_TAG" environment variable.

* When a collection is saved, its content starts with a "#%Module5.1"
  file signature if "--tag" option is recorded in it.

* Update the "restore", "savelist", "saveshow" and "is-saved" sub-
  commands to exclude from result or return an error when checking a
  collection expressing a higher Modules version requirement in its
  header signature than the one currently in use.

* Doc: describe differences between run-command file and modulefile
  interpretation in modulefile man page.

* Doc: describe "module" sub-commands available as modulefile Tcl
  command for each interpretation context in modulefile man page.

* When loading a module with some extra tags defined through the "--
  tag" option, if this module is already loaded the new tags are added
  to those already set.

* When reporting result of "avail" or "list" sub-commands, enclose
  module names in single quotes if they contain a space character.

* When mentioning the loading, unloading or refreshing evaluation of a
  module, report the tags associated to this module as done when
  printing results of "list" sub-command.

* Fix Log module command cookbook recipe not to break Modules
  initialization when using provided "siteconfig.tcl" file. (fix issue
  #453 with contribution from Eric Burgueño)

* Mention tagging evaluation of a module, when tag list of an already
  loaded module is updated.


Modules 5.0.1 (2021-10-16)
==========================

* Doc: add *How to preserve my loaded environment when running screen*
  entry in Frequently Asked Questions.

* Fix the advanced version specifier resolution when the
  "extended_default" option is off and "icase" option is on when
  resolving version list specification. (fix issue #411)

* Doc: improve the Log module command cookbook to rely on the "trace"
  Tcl command to track every modulefile evaluation and module/ml
  procedure calls. (fix issue #412)

* Doc: fix missing space between list entries in Variants design doc.
  (fix issue #413)

* Correctly detect tags set on loaded modules when refreshing them.

* Set the "__MODULES_AUTOINIT_INPROGRESS" environment variable when
  running the "autoinit" sub-command and quit autoinit process if this
  variable is found defined and equal to 1 when starting it. Ensure
  this way that an autoinit process will not be triggered indefinitely
  by itself when the "set_shell_startup" option is enabled and some
  module loaded at initialization time relies on the execution of a
  bash script. (fix issue #414)

* Remove warning message when unloading a "prepend-path" or "append-
  path" modulefile command with "--duplicates" option set. (fix issue
  #421)

* Clarify the module sub-commands that are allowed to be used within a
  modulefile. (fix issue #423)

* Install: set in the module magic cookie of the "initrc"
  configuration file installed by default the version of Modules
  required to evaluate this file.

* Doc: fix documentation of "getenv" modulefile command to describe
  that an empty string is now returned when designated environment
  variable is not defined and no default value to return is specified.


Modules 5.0.0 (2021-09-12)
==========================

* Remove deprecated **createmodule.sh** and **createmodule.py** tools
  as shell script to modulefile conversion is now achieved with the
  "sh-to-mod" sub-command.

* Remove mention of the "init*" sub-commands in module usage message
  to put focus on the collection handling sub-commands.

* Do not declare anymore the "chdir", "module", "module-trace",
  "module-verbosity", "module-user" and "module-log" commands under
  the modulerc Tcl interpreter as no-op commands. A clear error
  message is obtained if these commands are still used in modulerc
  files instead of silently ignoring them.

* Return by default an empty string rather "_UNDEFINED_" on "getenv"
  modulefile command if passed environment variable is not defined.

* Align empty directory name error message obtained on "use" sub-
  command with message obtained when module or collection name is
  empty.

* Accept non-existent modulepath on "use" sub-command.

* Install: installation option "--enable-auto-handling" is set on by
  default which enables the automated module handling mode (see
  "MODULES_AUTO_HANDLING").

* Install: installation option "--enable-extended-default" is set on
  by default which allows partial module version specification (see
  "MODULES_EXTENDED_DEFAULT").

* Install: installation option "--enable-advanced-version-spec" is set
  on by default which activates the Advanced module version specifiers

* Install: installation option "--enable-color" is set on by default
  which enables the "auto" output color mode (see "MODULES_COLOR").

* Install: installation option "--with-icase" is set to "search" by
  default to activate case insensitive match on search contexts (see
  "MODULES_ICASE").

* Install: installation option "--enable-new-features" has been reset
  following major version change as all the options it implied are now
  enabled by default.

* Install: installation option "--enable-set-shell-startup" is set off
  by default but could be enabled once installed through the "initrc"
  configuration file.

* Install: installation option "--with-initconf-in" is set to "etcdir"
  by default to locate configuration files in the directory designated
  by the "--etcdir" option. Therefore the initialization configuration
  file is named "initrc" in this directory, and the modulepath-
  specific configuration file is named "modulespath".

* Only look at configuration files found in the location designated by
  the "--etcdir" or "--initdir" option (depending on the value of "--
  with-initconf-in" option). Configuration files were previously
  searched in both locations.

* Install: remove installation option "--enable-compat-version".
  Compatibility version co-installation is discontinued. **switchml**
  shell function and "MODULES_USE_COMPAT_VERSION" are thus removed as
  well.

* Testsuite: introduce the non-regression quick test mode. When the
  "QUICKTEST" environment variable is set to "1", only the main tests
  from the non-regression testsuite are run. When first argument of
  the **mt** script is "quick", tests are run in quick mode.

* Install: run non-regression testsuite in quick mode in RPM spec
  file.

* Rename the environment variables that are used by Modules to track
  loaded environment state (variables whose name starts with
  "MODULES_LM"). A "__" prefix is added to the name of these variables
  to indicate that they are intended for internal use only.

* Rename the environment variables used to indirectly pass to
  "modulecmd.tcl" the value of variables set in quarantine (variables
  whose name finishes with "_modquar"). A "__MODULES_QUAR_" prefix is
  applied to the name of these variables instead of the "_modquar"
  suffix to indicate they are intended for Modules internal use of
  only.

* Update Tcl requirement to version 8.5 as Tcl 8.4 is deprecated since
  a long time and this version is not available anymore on recent OS
  distributions. Update internal code of "modulecmd.tcl" to take
  benefit from the features brought by Tcl 8.5.

* Split source code in several Tcl files hosted in "tcl" directory.
  When building Modules, the Tcl files are concatenated to make the
  "modulecmd.tcl" script.

* Record "auto-loaded" tag of loaded modules in "__MODULES_LMTAG"
  environment variable rather set a specific entry for module in the
  "__MODULES_LMNOTUASKED" environment variable.

* Rename the environment variables used by the reference counting
  mechanism of path-like environment variables. A "__MODULES_SHARE_"
  prefix is applied to the name of these variables instead of the
  "_modshare" suffix to clearly indicate they are intended for Modules
  internal use of only.

* Reference counting mechanism is not anymore applied to the Modules-
  specific path variables (like "LOADEDMODULES"). As a result no
  "__MODULES_SHARE_<VAR>" variable is set in user environment for
  these variables. Exception is made for "MODULEPATH" environment
  variable where the mechanism still applies.

* When an element is added to a path-like variable through the
  "append-path" or "prepend-path" modulefile commands, add this
  element to the associated reference counter variable (named
  "__MODULES_SHARE_<VAR>") only when this element is added multiple
  times to the path-like variable. When an element is removed from a
  path-like variable, this element is removed from the reference
  counter variable when its counter is equal to 1.

* When the "use" and "unuse" module sub-commands are not called during
  a modulefile evaluation, the reference counter associated with each
  entry in "MODULEPATH" environment variable is ignored. In such
  context, a "module use" will not increase the reference counter of a
  path entry already defined and a "module unuse" will remove
  specified path whatever its reference counter value.

* When the "append-path", "prepend-path" and "remove-path" module sub-
  commands are not called during a modulefile evaluation, the
  reference counter associated with each entry in targeted environment
  variable is ignored. In such context, a "module append-path/prepend-
  path" will not increase the reference counter of a path entry
  already defined and a "module remove-path" will remove specified
  path whatever its reference counter value.

* Fix "unuse" sub-command when several modulepaths are specified as a
  single argument (i.e., "/path/to/dir1:/path/to/dir2"). Enabled
  modulepaths were not correctly detected when specified this way.

* Doc: clarify that an already defined path is not added again or
  moved when passed to the "use" sub-command or the "append-path
  /prepend-path" modulefile commands. (fix issue #60)

* Change the "refresh" sub-command to evaluate all loaded modulefiles
  and re-apply the non-persistent environment changes they define
  (i.e., shell aliases and functions). With this change the "refresh"
  sub-command is restored to the behavior it had on Modules version
  3.2.

* Evaluate the modulefile commands resulting from a "source-sh"
  command through the current modulefile Tcl interpreter in order to
  evaluate them according to the current modulefile evaluation mode.

* When initializing Modules, refresh the loaded modules in case some
  user environment is already configured. This is especially useful
  when starting a sub-shell session as it ensures that the loaded
  environment in parent shell is correctly inherited, as the "refresh"
  sub-command re-applies the non-persistent environment configuration
  (i.e., shell alias and function that are not exported to the sub-
  shell). (fix issue #86)

* Init: add example code in default "initrc", the initialization
  script of Modules, to either restore user's default collection if it
  exists or load a predefined module list at the end of the
  initialization process.

* When initializing Modules, evaluate the "initrc" configuration file
  in addition to the the "modulespath" configuration file and not
  instead of this file. "initrc" is evaluated after "modulespath"
  file.

* When the installation option "--enable-modulespath" is set, the list
  of modulepath to enable by default is now only defined in the
  "modulespath" configuration file and not anymore in the "initrc"
  configuration file.

* No error is raised when evaluating in "display" mode a modulefile
  without a value specified for the "variant" it defines. This change
  helps to learn all the variant a modulefile defines. As a result,
  the unspecified variant is not instantiated in the "ModuleVariant"
  array variable. (fix issue #406)

* When running the "unsetenv" modulefile command on an unload
  evaluation, do not unset designated environment variable if no value
  to restore is provided.

* Fix "unsetenv" to distinguish between being called on a unload
  evaluation without a value to restore or with an empty string value
  to restore.

* Make "system" modulefile command available from a modulerc
  evaluation context whatever the underlying module evaluation mode.

* Make "is-used" modulefile command available from a modulerc
  evaluation context.

* Remove internal state "tcl_version_lt85" as Tcl 8.5+ is now a
  requirement.

* Forbid use of "module source" command in modulefile or in an
  initialization rc file, the "source" Tcl command should be used
  instead. "source" sub-command should only be called from the
  command-line.

* Report the modules loading and unloading during the **module**
  command initialization (i.e., during the evaluation of the "initrc"
  configuration file). These report messages are disabled when the
  "verbosity" configuration option is set to "concise" or "silent".

* During a module "restore" or "source", only report the module load
  and unload directly triggered by these sub-commands. Load and unload
  triggered by other modules are reported through the automated module
  handling messages of the main modules.

* Enforce use of the module magic cookie (i.e., "#%Module") at the
  start of global or user rc files, "initrc" configuration file or any
  scriptfile passed for evaluation to the "source" sub-command. These
  files are not evaluated and an error is produced if the magic cookie
  is missing or if the optional version number placed after the cookie
  string is higher than the version of the "modulecmd.tcl" script in
  use.

* Doc: alphabetically sort installation option in Installing Modules
  on Unix document.

* Update the "--enable-quarantine-support" installation option to
  control a "quarantine_support" configuration option. When this
  option is enabled, the "autoinit" sub-command produces the shell
  code for the **module** shell function definition with quarantine
  mechanism support. When disabled, code is generated without
  quarantine support.

* Install: installation option "--enable-quarantine-support" is set
  off by default.

* Introduce the "MODULES_QUARANTINE_SUPPORT" environment variable to
  control the "quarantine_support" configuration option once Modules
  is installed. To enable the quarantine mechanism,
  "MODULES_QUARANTINE_SUPPORT" should be set to "1" prior Modules
  initialization or "quarantine_support" configuration option should
  be set to "1" in the "initrc" configuration file.

* Quarantine mechanism code in the Modules shell initialization
  scripts is now always defined and mechanism always applies if some
  environment variables are defined in "MODULES_RUN_QUARANTINE".

* Code in the "modulecmd.tcl" script to restore environment variables
  put in quarantine is now always generated and applies if the
  "__MODULES_QUARANTINE_SET" environment variable is set to "1". This
  variable is set by the Modules initialization script prior calling
  the "autoinit" sub-command or by the **module** shell function if it
  has been generated with quarantine support enabled.

* Install: installation option "--enable-silent-shell-debug-support"
  is set off by default.

* Code to silence shell debug properties in the Modules shell
  initialization scripts is now always defined and mechanism applies
  if "MODULES_SILENT_SHELL_DEBUG" environment variable is set to "1".

* Code to silence shell debug properties in the **module** shell
  function could now be enabled if "MODULES_SILENT_SHELL_DEBUG" is set
  to "1" prior Modules initialization or if the "silent_shell_debug"
  configuration option is set to "1" in the "initrc" configuration
  file.

* Doc: clarify TOC and title of MIGRATING document.

* Doc: extend description of Modules configuration steps of in
  Installing Modules on Unix document.

* Doc: document "initrc" and "modulespath" configuration files in
  module man page.

* Install: replace "example.txt" by "INSTALL.txt" guide in RPM.

* Doc/Install: rename "diff_v3_v4" document into changes.

* Doc: reorganize Changes between versions document to let room to
  describe Modules 5 changes.


Modules 4.8.0 (2021-07-14)
==========================

* Introduce the "edit" sub-command that opens modulefile passed as
  argument in a text editor. Modulefile can be specified like with any
  other sub-command, leveraging defined symbolic versions, aliases or
  using advanced version specifiers.

* Add the "editor" configuration option to select the text editor to
  use with "edit" sub-command. When this option is set through the
  "config" sub-command, the "MODULES_EDITOR" environment variable is
  set. The "--with-editor" installation option controls the default
  value of "editor" configuration option. If not set at installation
  time, "vi" is set as default editor.

* Default value of "editor" configuration option is overridden by the
  "VISUAL" or the "EDITOR" environment variables, which are both in
  turn overridden by the "MODULES_EDITOR" environment variable.

* Doc: fix "modulecmd.tcl" internal state check in recipes example
  codes. (fix issue #396)

* The Advanced module version specifiers mechanism now allows the use
  of version range in version list (for instance
  "mod@:1.2,1.4:1.6,1.8:"). Such specification helps to exclude
  specific versions. (fix issue #397)

* Install: fix installation scripts to allow building Modules when its
  repository is set as a git submodule. (fix issue #398)

* Doc: demonstrate in the Source shell script in modulefile recipe how
  to use the "source-sh" command when software provide a specific
  initialization script for each shell it supports. (fix issue #399)

* When defining a shell function with the "set-function" modulefile
  command, only export this function when using the Bash shell (using
  the "export -f" shell command) to make it available in sub-shell
  contexts. Shell function export is not supported on other kind of sh
  shell (sh, ksh and zsh). (fix issue #401)

* Doc: add Variants design notes.

* Add the "variant" modulefile command that enables to pass down
  arguments, specified when designating the module to evaluate, within
  modulefile evaluation context. This command defines a variant name
  and a list of allowed values. When evaluated, "variant" instantiates
  an element in the "ModuleVariant" array whose name equals variant
  name and value is set with value specified for variant when module
  is designated. If specified value does not correspond to an allowed
  value or if no value is specified for variant an error is raised.

* Enhance the Advanced module version specifiers to handle variant
  specification following Spack's syntax (e.g., *name=value*). When
  the "advanced_version_spec" configuration is enabled, variant could
  be specified anywhere a module can be specified.

* Add the "--default" option to the "variant" modulefile command to
  indicate the default value of the variant to apply when the
  designation of the evaluating module does not mention this variant.

* Add the "--boolean" option to the "variant" modulefile command to
  indicate that the variant defined is of the Boolean type, thus no
  list of accepted value is expected.

* Enhance the Advanced module version specifiers to handle Boolean
  variant specification following Spack's syntax (e.g., *+name*,
  *~name* and *-name*). The *-name* syntax is not supported on ml
  command as the minus sign already means to unload designated module.

* Accept any minus argument (*-word*) set after the sub-command name
  when the "advanced_version_spec" configuration is enabled and if
  sub-command accepts Advanced module version specifiers (like "load"
  or "unload" sub-commands). A *false* value may be set to Boolean
  variant this way.

* Add the "variant_shortcut" configuration option to define shortcut
  characters that could be used to specify and report module variants.
  Default value for this option could be set at installation time with
  the "--with-variant-shortcut" option. No variant shortcut is defined
  by default. This value could be superseded by setting up the
  "variant_shortcut" option with "config" sub-command. Which sets the
  "MODULES_VARIANT_SHORTCUT" environment variable.

* Enhance the Advanced module version specifiers to handle variant
  shortcut specification (e.g., *<shortcut>value*).

* Record in user loaded environment, with "MODULES_LMVARIANT"
  environment variable, the value specified for the variants defined
  in the loaded modulefiles and their properties (if it is a Boolean
  variant and if the value set is the default one).

* Add the "variant" element in the allowed value list of the
  "list_output" and "list_terse_output" configuration options. Set
  this new element in the default value list of the "list_output"
  option. When set, the variant defined for loaded modules are
  reported on module "list" command output.

* Add the "va" color key in default light and dark color palettes to
  graphically enhance the report of variant value.

* Update the key section to explain on "list" sub-command output the
  reported variant elements (*name=value*, *+name*, *-name* or
  *<shortcut>value*)

* Record variant specification of loaded modules when saving
  collections and reload specified variants when restoring these
  collections.

* When "collection_pin_version" configuration is disabled, only record
  in collections the variants whose value is not the default one.

* Update module designation in error, warning or informational
  messages to report variant specification enclosed in curly braces
  (*{}*), enclose module name and version or variant specification in
  single quotes (*''*) if they contain a space character and highlight
  the module designation in report message if configured.

* Introduce the "getvariant" modulefile command to query for currently
  evaluating module the value of a given variant name.

* When translating the "@loaded" version specifier also retrieve the
  variant specified for corresponding loaded module.

* Update hide, forbid and tag mechanisms to apply them only if they
  match selected module variant.

* Any variant defined in module specification passed as argument to
  search sub-commands ("avail", "whatis", "is-avail", "path" and
  "paths") is ignored.

* Raise an error if a variant named "version" is declared in a
  modulefile to let room for the future implementation of this
  specific variant.

* Doc: describe in the Changes between versions document argument
  handling change on "setenv" since v3.2. (fix issue #402)

* Introduce the "try-load" sub-command which like "load" sub-command
  tries to load the modulefile passed as argument, but does not
  complain if this modulefile cannot be found. (fix issue #392)

* Init: fix stderr redirection in fish shell initialization script,
  now that use of the "^" character to redirect stderr is disabled by
  default (fish >=3.3).

* Protect quarantine mechanism code from "rcexpandparam" Zsh option
  when initializing the **module** command on this shell. (fix issue
  #403)


Modules 4.7.1 (2021-04-06)
==========================

* Doc: clarify the license terms used by the project. (fix issue #389)

* Align all files from the Modules project under the GPLv2+ license.
  Scripts and libraries that were previously licensed with GPLv3+ have
  been moved to GPLv2+ with the consent of their respective copyright
  holders. (fix issue #389)

* Revert "Install: have "configure" script assume the "." dot
  directory when invoked without the prepended "./"" as consent was
  not obtained from author to re-license the contribution to GPLv2+.

* Doc: fixes few typos in module and modulefile.

* Update the "sh-to-mod" mechanism to support version 3.2 of the fish
  shell. Fish 3.2 introduces the "." builtin command that should be
  regexp-escaped when determining the shell functions or aliases
  defined by the script analyzed by "sh-to-mod".

* Vim: update addon files to highlight modulefile variables
  "ModuleTool", "ModuleToolVersion" and "ModulesCurrentModulefile".

* Doc: update the description and default value of the "--with-dark-
  background-colors" and "--with-light-background-colors" installation
  options.

* Doc: add description of changes that occurred on versions 4.6 and
  4.7 for the "--with-dark-background-colors" and "--with-light-
  background-colors" installation options and for the "MODULES_COLORS"
  environment variable.

* Doc: correct the default value of the "--with-tag-abbrev"
  installation option.

* Doc: add Sticky modules cookbook recipe.


Modules 4.7.0 (2021-02-19)
==========================

* Doc: simplify TOC of New features document

* Add the "ModuleTool" and "ModuleToolVersion" Modules variables to
  determine during modulefile or modulerc evaluation the name and
  version of the *module* implementation currently in use.

* Introduce the "versioncmp" modulefile command to compare two version
  strings passed as argument.

* Enable the use of wildcard character to designate multiple
  directories at once in "modulespath" configuration file. (fix issue
  #125)

* Distinguish aliases from symbolic versions in "MODULES_LMALTNAME"
  environment variable. Prefix these alias entries with the "al|"
  string.

* Fetch modulefile modification time only if required by "list" sub-
  command display format.

* Use symbolic versions recorded in environment, with
  "MODULES_LMALTNAME" variable, to report the symbols applying to
  loaded modules on "list" sub-command. Modulerc files are not
  evaluated anymore when performing a module list.

* Move the definition of the "FPATH" environment variable for Modules
  initialization on ksh shell from the initialization script of this
  shell to the resulting output of the "autoinit" sub-command.

* Introduce the "shells_with_ksh_fpath" configuration option to define
  a list of shell where to ensure that any ksh sub-shell will get the
  module function defined by use of the "FPATH" environment variable.
  When the "shells_with_ksh_fpath" option is set through the "config"
  sub-command, the "MODULES_SHELLS_WITH_KSH_FPATH" environment
  variable is set. Accepted values are a list of shell among *sh*,
  *bash*, *csh*, *tcsh* and *fish* separated by colon character (":").

* Add the "implicit_requirement" configuration option to control
  whether a prereq or a conflict requirement should be implicitly set
  onto modules respectively specified on "module load" or "module
  unload" commands in modulefile. Default value for this option could
  be set at configure time with the "--enable-implicit-requirement"
  option (enabled by default). This value could be superseded by
  setting up the "implicit_requirement" option with "config" sub-
  command. Which sets the "MODULES_IMPLICIT_REQUIREMENT" environment
  variable. (fix issue #260)

* Add the "--not-req" option to the "module" modulefile command to
  inhibit for its "load" and "unload" sub-commands the definition of a
  prereq or conflict requirement onto specified modules.

* Add the "lpopState" and "currentState" procedures to respectively
  remove or return the last entry from the list of values of a given
  state.

* Add the "topState" and "depthState" procedures to respectively
  return the first element from or the number of elements in the list
  of values of a given state.

* Remove the pre-definition of runtime states with no specific
  property. These basic states are defined on-the-fly which implied
  they are not reported on a "module config --dump-state" command
  unless if instantiated.

* Introduce the "loaded" symbolic version among advanced version
  specifiers (e.g. "foo@loaded") to designate the currently loaded
  version of specified module. (fix issue #366)

* Doc: add *Module tags* design notes.

* Report tags applying to the modules returned by the "avail" sub-
  command. Adapt the regular, terse and JSON output styles to report
  these tags along the module they are attached to (enclosed in "<>").
  Reported tags currently are states that apply to modules: "auto-
  loaded", "forbidden", "hidden", "loaded", "nearly-forbidden",
  "sticky" and "super-sticky".

* Record tags applying to each loaded module in the "MODULES_LMTAG"
  environment variable to make this information persist after module
  being loaded.

* Report tags applying to the loaded modules returned by the "list"
  sub-command. Adapt the regular and JSON output styles to report
  these tags along the module they are attached to (enclosed in "<>").
  Reported tags currently are states applying to loaded modules:
  "auto-loaded", "hidden-loaded", "nearly-forbidden", "sticky" and
  "super-sticky".

* Introduce the "module-info tags" modulefile command to query the
  tags that apply to the currently evaluated modulefile.

* Add the "module-tag" modulefile command to associate tag to
  designated modulefile. Those tags are reported on "avail" and "list"
  sub-commands along the module they are attached to. "module-tag"
  supports the advanced module version specifier syntax.

* Add the "tag_abbrev" configuration option to define abbreviated
  strings for module tags and use these abbreviations instead of tag
  names when reporting tags on "avail" and "list" command results.
  Default value for this option could be set at configure time with
  the "--with-tag-abbrev" option. By default the following
  abbreviations are set: "aL" for *auto-loaded*, "F" for *forbidden*,
  "H" for *hidden*, "H" for *hidden-loaded*, "L" for *loaded*, "nF"
  for *nearly-forbidden*, "S" for *sticky*, "sS" for *super-sticky*.
  This value could be superseded by setting up the "tag_abbrev" option
  with "config" sub-command. Which sets the "MODULES_TAG_ABBREV"
  environment variable.

* A Select Graphic Rendition (SGR) code can be associated to module
  tag names or abbreviation strings in the color palette to
  graphically render these tags over the module name they are
  associated to. The default light and dark color palettes have been
  updated to set a color code for all basic module tags. When a color
  code is set for a tag, it is then graphically rendered over the
  module names and not reported along module name by its tag name or
  abbreviation. When multiple colored tags apply to a given module,
  each tag is graphically rendered over a sub-part of the module name.

* Add the "tag_color_name" configuration option to designate module
  tags whose graphical rendering should be applied to their own name
  or abbreviation rather than over the module name they are attached
  to. Default value for this option could be set at configure time
  with the "--with-tag-color-name" option (empty by default). This
  value could be superseded by setting up the "tag_color_name" option
  with "config" sub-command. Which sets the "MODULES_TAG_COLOR_NAME"
  environment variable.

* Add the "--hidden-loaded" option to the "module-hide" modulefile
  command that indicates module should be hidden once loaded. When
  set, the "hidden-loaded" module tag applies to module specification
  set on "module-hide" command.

* Do not report on "list" sub-command results the loaded modules
  associated with the "hidden-loaded" tag, unless if the "--all"
  option is set.

* Doc: add an "hidden-loaded" example in the *Hide and forbid modules*
  cookbook recipe.

* Introduce the "verbose2" verbosity level between "verbose" and
  "trace" levels. Verbose2 mode can be enabled by setting the
  "verbosity" config to the "verbose2" value or by using the "-v"
  command-line switch twice.

* Do not report the load, unload or switch of modules set "hidden-
  loaded" if these modules have been loaded, unloaded or switched
  automatically. Unless the verbosity mode is set to "verbose2" or any
  higher level or if any specific messages have to be reported for
  these module evaluations.

* Report when trying to load a module which is already loaded or when
  trying to unload a module which is not loaded in case the verbosity
  mode is set to "verbose2" or any higher level. (fix issue #187)

* Doc: improve readability of version 4 improvements in Changes
  between versions document.

* Introduce stickiness: module tagged "sticky" with "module-tag"
  command cannot be unloaded unless if the unload is forced or if the
  module is reloaded. (fix issue #269)

* Introduce super-stickiness: module tagged "super-sticky" with
  "module-tag" command cannot be unloaded even if the unload is forced
  unless if the module is reloaded. (fix issue #269)

* Allow swap of sticky or super-sticky modules by another modulefile
  version if stickiness definition applies to module parent name.
  E.g., *foo/1.0* can be swapped by *foo/2.0* if sticky tag applies to
  *foo*.

* When forcing purge with a "purge --force" sub-command, also unload
  the modules that are depended by non-unloadable modules.

* Doc: improve readability of Modules installation configuration in
  Installing Modules on Unix document and enable hypertext reference
  to these elements.

* Doc: improve readability of module command configuration option in
  module document and enable hypertext reference to these elements.

* Doc: describe in HTML documentation when installation options,
  module command configuration options and options of modulefile
  command or module sub-command were introduced.

* Doc: update HTML documentation Table Of Content.

* Doc: improve markup of module sub-commands, modulefile commands,
  installation option, module configuration option across
  documentation.

* Doc: colorize terminal output examples in New features document.

* Abort modulefile read if first file content chunk does not start
  with the "#%Module" magic cookie. (fix issue #375)

* Install: add installation option "--enable-new-features" that
  enables all at once the installation options that are disabled by
  default due to the substantial behavior changes they imply.

* Add a *Key* section at the end of "avail" and "list" sub-commands to
  explain the meaning of graphical renditions or of elements set in
  parentheses or chevrons along module name.

* Fix output of "avail" and "list" sub-commands on very small terminal
  width. (fix issue #378)

* Add "mcookie_version_check" configuration to define if version set
  in modulefile magic cookie should be checked against **module**
  current version to determine if modulefile can be evaluated. The new
  configuration, which is enabled by default, can be set at
  installation time with configure option "--enable-mcookie-version-
  check" or can be superseded later on with the
  "MODULES_MCOOKIE_VERSION_CHECK" environment variable. (fix issue
  #377)

* Fix output of modulefile evaluation error stack trace on very small
  terminal width. (fix issues #379 and #381)

* Correct "config" sub-command to set "nearly_forbidden_days"
  configuration. (fix issue #380)

* Init: reduce usage of helper variables in "bash_completion" and
  "tcsh_completion" that are showing up in the output of the shell's
  "set" command. (fix issue #382 with contribution from Colin
  Marquardt)

* Consider modulepath starting with a reference to an environment
  variable as absolute. (fix issue #376)

* Consider the "module load" performed in the user or the global RC
  file like load commands issued from initialization RC file. (fix
  issue #372)

* Install: have "configure" script assume the "." dot directory when
  invoked without the prepended "./". (contribution from R.K. Owen)

* Install: disable the Makefile rules to build the HTML documentation
  in case if the documentation is found pre-built in the dist archive.

* Install: do not flag documentation as pre-built if "configure"
  script is ran another time after building docs.

* Restrict the value accepted by "nearly_forbidden_days" configuration
  and "--with-nearly-forbidden-days" installation option to integers
  comprised between 0 and 365.

* Install: color *ERROR* and *WARNING* message headers produced by
  "configure" script if output is sent to a terminal.

* Install: split error messages produced by "configure" script over an
  additional line when too long.

* Doc: add *Output configuration* design notes.

* Introduce the "avail_output" and "avail_terse_output" configuration
  options to define the content to report in addition to the available
  module names respectively for "avail" sub-command regular and terse
  output modes. Excepted value for these configuration options is a
  colon separated list of elements to report. Default value is
  "modulepath:alias:dirwsym:sym:tag:key" for "avail_output" and
  "modulepath:alias:dirwsym:sym:tag" for "avail_terse_output". These
  values can be changed at installation time respectively with the "--
  with-avail-output" and "--with-avail-terse-output" options. These
  values can then be superseded by using the "config" sub-command
  which sets the "MODULES_AVAIL_OUTPUT" and
  "MODULES_AVAIL_TERSE_OUTPUT" environment variables.

* Introduce the "list_output" and "list_terse_output" configuration
  options to define the content to report in addition to the available
  module names respectively for "list" sub-command regular and terse
  output modes. Excepted value for these configuration options is a
  colon separated list of elements to report. Default value is
  "header:idx:sym:tag:key" for "list_output" and "header" for
  "list_terse_output". These values can be changed at installation
  time respectively with the "--with-list-output" and "--with-list-
  terse-output" options. These values can then be superseded by using
  the "config" sub-command which sets the "MODULES_LIST_OUTPUT" and
  "MODULES_LIST_TERSE_OUTPUT" environment variables.

* Add the "--output"/"-o" command-line switches to supersede the
  output configuration of "avail" or "list" sub-commands on their
  regular or terse output modes.

* Remove the "avail_report_dir_sym" and "avail_report_mfile_sym"
  locked configuration options whose behaviors can now be obtained by
  respectively adding the "dirwsym" and "sym" elements to the
  "avail_output" or "avail_terse_output" configuration options.

* When "modulepath" is omitted from the content to report on "avail"
  sub-command, available modules collected from global/user rc and
  enabled modulepaths are aggregated and reported all together.

* Install: print generated file names rather commands executed to
  generate these files on Makefile build targets. Output obtained when
  building Modules is this way simplified. When option "V=1" is passed
  to "make", the verbose mode is enabled and run commands are shown.
  The simplified "make" output does not apply to the install, test and
  clean targets or any target similar to them.

* Install: fix configure and build files of Modules Tcl extension
  library to make them compatible with autoconf >=2.69.

* Script: correctly detect previous Modules version number released
  from a side git branch on **mpub** command.

* Install: align RPM spec file syntax with spec file used on Fedora.
  Add missing build dependency on "make" package. Also remove obsolete
  "Group" RPM tag.

* Add the "term_width" configuration option to set the width of the
  output. This configuration option is set to "0" by default, which
  means that the output width is the full terminal width. The "--
  width"/"-w" command line switches are added to supersede the value
  of the configuration option. (fix issue #359 with contribution from
  Anaïs Gaertner)

* Doc: add a *Get Modules* section in Installing Modules on Unix
  document to provide download links for Modules' sources. (fix issue
  #387)


Modules 4.6.1 (2020-11-14)
==========================

* Lib: implement "initStateClockSeconds" as a Tcl command in
  libtclenvmodules to provide an optimized way to retrieve current
  Epoch time.

* Lib: implement "parseDateTimeArg" as a Tcl command in
  libtclenvmodules to provide an optimized way to convert a datetime
  string into an Epoch time.

* When full module specification is equal to "@", raise an error as no
  module name is provided. (fix issue #362)

* Optimize internal recording of hidden module and tag specification
  when parsing modulerc files in order to reduce the time taken to
  test if a given module is hidden or if a given tag applies to it.

* Script: add the ability to select the benchmark test to perform on
  **mb** utility.

* Doc: add *Use new features without breaking old module command*
  cookbook recipe

* Doc: rework option description for "module-hide" and "module-forbid"
  commands in modulefile document.

* Doc: describe in Changes between versions document that shell
  special characters like backticks are escaped when used in values
  starting Modules 4.0. (fix issue #365)

* Doc: make the ENVIRONMENT section from modulefile man page point to
  the ENVIRONMENT section of module man page.

* Fix "clear" sub-command to unset the "MODULES_LMSOURCESH"
  environment variable. (fix issue #367)

* Correctly return on "avail" sub-command a symbolic version defined
  in a global RC file when specifically searched. (fix issue #368)

* Fix module hiding resolution for symbolic versions defined in a
  global RC file when "module-hide" statements are set in the
  modulepath where the modulefiles targeted by these symbols are
  located. (fix issue #369)

* When a module fails to unload during a "purge" sub-command, preserve
  loaded the modules it requires to keep environment consistent. (fix
  issue #370)

* Doc: add *Hide and forbid modules* cookbook recipe.


Modules 4.6.0 (2020-09-16)
==========================

* Rework internal state handling to gather all state definitions in a
  global array and use the same initialization and retrieval
  procedure, named "getState", for all these states.

* Add the "setState", "unsetState", "lappendState", "isStateDefined"
  and "isStateEqual" procedures to provide unified ways to set or
  check the value of state.

* Introduce the "sh-to-mod" sub-command, to evaluate shell script and
  determine the environment changes it does. Corresponding modulefile
  content is outputted as a result. Changes on environment variables,
  shell aliases, shell functions and current working directory are
  tracked. The following shells are supported: sh, dash, csh, tcsh,
  bash, ksh, ksh93, zsh and fish.

* Doc: add *Source shell script in modulefile* design notes.

* Introduce the "source-sh" modulefile command, to evaluate shell
  script and apply resulting environment changes through modulefile
  commands. When a modulefile using "source-sh" modulefile command is
  loaded, the modulefile commands resulting from shell script
  evaluation are recorded in the "MODULES_LMSOURCESH" environment
  variable to be able to undo these environment changes when
  modulefile is unloaded and to report the modulefile commands used
  when modulefile is displayed. The same kind of environment changes
  than the "sh-to-mod" sub-command are tracked. The same list of
  shells than "sh-to-mod" sub-command are supported. (fix issue #346)

* Doc: add *Source shell script in modulefile* cookbook recipe.

* Doc: embed new Modules logo on website, online README and
  documentation portal.

* Install: disable by default the build of Modules compatibility
  version. From now on, option "--enable-compat-version" has to be set
  to trigger this build.

* Introduce the "username" sub-command to the "module-info" modulefile
  command to get the username of the user currently running
  "modulecmd.tcl" or to test a string passed as argument corresponds
  to this username.

* Introduce the "usergroups" sub-command to the "module-info"
  modulefile command to get all the groups of the user currently
  running "modulecmd.tcl" or to test a string passed as argument
  corresponds to one of these groups.

* Doc: improve markup of Release notes and New features documents
  starting from this 4.6 version to enable references to module sub-
  commands, command line switches, environment variables and
  modulefile Tcl commands.

* Use inclusive terminology to eliminate *master* and *slave* terms as
  much as possible from code source and documentation.

* Doc: use a versioned magic cookie in examples that demonstrate new
  modulefile features. (fix issue #349)

* Introduce the "--enable-multilib-support" configure option to add
  mechanism in "modulecmd.tcl" to look at an alternative location to
  find the Modules Tcl extension library in case this library cannot
  be found at its main location.

* Lib: remove *fetch_hidden* argument from "getFilesInDirectory"
  procedure of Modules Tcl extension library.

* Doc: add *Hide or forbid modulefile* design notes.

* Add the "module-hide" modulefile command, to dynamically hide
  modulefile, module alias or symbolic version matching passed
  specification. When hidden, a modulefile, an alias or a symbolic
  version is not reported nor selected unless referred by its exact
  name, like for module whose name or version starts with a dot
  character. "module-hide" supports the advanced module version
  specifiers. (fix issue #202)

* Add option "--soft" to the "module-hide" modulefile command to
  introduce a soften level of camouflage: modules targeted by such
  hide directive are made visible as soon as their root name is part
  of search query.

* Add option "--hard" to the "module-hide" modulefile command to
  introduce a hardened level of camouflage: modules targeted by such
  hide directive keep being hidden even if they are fully matched by
  search query.

* Do not report among "whatis" search result the modulefiles with
  version name prefixed by a dot character and targeted by a symbolic
  version unless if they are precisely searched.

* When a loading module has hidden alternative names (hidden due to
  their name or version starting with a dot character or because they
  match a "module-hide" statement), these alternative names are not
  recorded in environment unless if they are not hard-hidden and if
  they have been used in query to select loading module.

* On "avail" sub-command, remove hidden symbolic versions from the
  list to display along modulefile or directory they target, unless
  these symbols are not hard-hidden and are used in query to search
  modules.

* When the "--default" filter of "avail" sub-command is set, unhide
  all the *default* symbolic versions or modules targeted by these
  symbols unless if they are hard-hidden.

* Define the *default* and *latest* automatic symbolic versions only
  if relative module name matches search query to ensure all elements
  for this module have been processed prior assigning the symbols.

* In case a symbolic version is transitively applied toward a
  modulefile, like for instance when this symbol is first set onto a
  directory, record the resolution of each transitively applied
  symbol. By doing so, a module "load" tentative using the
  transitively applied symbolic version will now correctly resolve to
  the modulefile targeted by symbol.

* Fix use of the advanced version specifiers in arguments to the "is-
  avail" modulefile command.

* Introduce the "--all"/"-a" option for "avail", "aliases", "whatis"
  and "search" sub-commands, to include in the search process all
  hidden modulefiles, module aliases or symbolic versions. Hard-hidden
  modules stay hidden even if "--all"/"-a" option is used.

* Add the "module-forbid" modulefile command, to dynamically forbid
  evaluation of modulefile matching passed specification. When
  forbidden, a module cannot be loaded and an access error is obtained
  when trying to evaluate them. "module-forbid" supports the advanced
  module version specifiers.

* Add "--not-user" and "--not-group" options to "module-hide" and
  "module-forbid" modulefile commands to ignore hiding or forbidding
  definition if current user is respectively part of specified
  username list or member of one of specified group list.

* Add "--before" and "--after" options to "module-hide" and "module-
  forbid" modulefile commands to ignore hiding or forbidding
  definition respectively after and before a specified date time.
  Accepted date time format is "YYYY-MM-DD[THH:MM]".

* Add "--message" option to "module-forbid" modulefile command to
  supplement the error message obtained when trying to evaluate a
  forbidden module.

* When a module that will soon be forbidden (as the date limit
  specified on the "--after" option of a matching "module-forbid"
  command is near) is evaluated, warn user this module access will
  soon be denied.

* The range of time the above warning appears can be controlled with
  the "nearly_forbidden_days" configuration option, whose value equals
  to the number of days prior the module starts to be forbidden. This
  configuration is set to "14" (days) by default and this value can be
  controlled at "configure" time with "--with-nearly-forbidden-days"
  option. When the "nearly_forbidden_days" configuration is set
  through the "config" sub-command, the
  "MODULES_NEARLY_FORBIDDEN_DAYS" environment variable is set.

* Add "--nearly-message" option to "module-forbid" modulefile command
  to supplement the warning message obtained when evaluating a nearly
  forbidden module.

* Add the "debug2" verbosity level, to report each call of
  "modulecmd.tcl" internal procedures in addition to debug messages.
  Debug2 mode can be enabled by setting the "verbosity" config to the
  "debug2" value or by using the "-D" command-line switch twice.

* Install: look for "make" rather "gmake" on MinGW and build library
  with a ".dll" extension on this platform.

* Add the "trace" verbosity level, to report details on module
  searches, resolutions, selections and evaluations. Trace mode can be
  enabled by setting the "verbosity" config to the "trace" value or by
  using the "-T"/"--trace" command-line switches.

* Introduce the "tr" key in the color palette to specifically render
  trace messages. Default value for "tr" key is "2" (decreased
  intensity).

* When trying to set an environment variable to an empty value on the
  Windows platform, unset this environment variable instead to cope
  with the underlying OS behavior.


Modules 4.5.3 (2020-08-31)
==========================

* Install: take into account the "--build", "--host", "--target", "--
  enable-dependency-tracking" and "--disable-dependency-tracking"
  configure options to transmit them to the "configure" scripts of
  Modules Tcl extension library and Modules compatibility version.
  (fix issue #354)

* Install: ignore some regular options of an Autoconf "configure"
  script that are useless for this project but usually implied in
  build macros (like RPM "%configure" macro).

* Install: ignore unsupported "--enable-*" and "--with-*" options on
  "configure" script rather raise an error and add support to define
  environment variable and build system type as "configure" script
  arguments to comply with GNU configuration recommendations.

* Install: fix "modulecmd" pre-alternatives check in RPM spec file.

* Install: use "%make_build" and "%make_install" macros in RPM spec
  file.

* When "module switch" command is used in modulefile, do not state
  when processing it a conflict over switched-off module if its
  specification on the "module switch" command also matches switched-
  on module's specification. Allow this way the replacement of any
  loaded version of a module for a specific one required by currently
  loading module. (fix issue #355)

* Correctly report failed attempts to load module requirements
  expressed with advanced version specifiers. (fix issue #356)


Modules 4.5.2 (2020-07-30)
==========================

* Init: "list" and "source" sub-commands do not take available modules
  as argument in fish completion script.

* Init: fix option list for "search" sub-command in bash completion
  script.

* Fix double error counter increase when modulefile evaluation breaks.

* Install: adapt "configure" script to pass to the "configure" script
  of Modules compatibility version only a subset of the options it
  supports (most commonly used options).

* Install: raise an error when an unknown option is passed to
  "configure" script rather silently ignore it. (fix issue #348)

* Install: enable the definition of installation directory options of
  "configure" script with the "--option value" syntax in addition to
  the "--option=value" syntax. (fix issue #348)

* Doc: alphabetically sort sub-commands of "module-info" modulefile
  Tcl command in modulefile document.

* Script: clean previously built environment-modules RPMs in **mrel**.

* Clearly separate quarantine variable definition from tclsh binary on
  "modulecmd.tcl" evaluated command call in "_module_raw" function for
  *sh*, *bash*, *ksh* and *zsh* shells. (fix issue #350)

* Doc: clarify in documentation index that Environment Modules should
  not be confused with language-specific modules. (contribution from
  Rob Hurt)

* Adapt conflict detection tests to ensure a module loaded by its full
  pathname will not detect itself as a conflict when declaring a
  reflexive conflict. (fix issue #352)

* Adapt the **mrel** and **mpub** commands to produce new Modules
  release from a *vZ.Y.x* git branch rather than from the repository
  main branch.


Modules 4.5.1 (2020-06-01)
==========================

* Install: consistently output Makefile warning messages on stderr.

* Script: add the "mrel" script, that automates build of the Modules
  release files and performs tests over these distribution files to
  guaranty their correctness.

* Script: add the "mpub" script, that automates Modules new release
  publishing over git repositories and websites.

* Install: remove project-specific tools from git repository export
  thus from release distribution files.

* Disable pager when "clear" sub-command is called from "ml" shortcut
  command. (fix issue #338)

* In case a modulefile evaluation fails, environment context prior
  this failed evaluation is restored. Fix environment variable
  restoration mechanism to keep the link that monitors and updates
  environment variable array "env" in every Tcl sub-interpreters. (fix
  issue #340)

* Ensure environment variable change at the Tcl interpreter level is
  propagated to every sub-interpreters used to evaluate modulefiles or
  modulercs. (fix issue #342)

* Use absolute path to load Modules Tcl extension library. (fix issue
  #344 with contribution from Roy Storey)

* Fix formatting of error stack trace not to look for internal
  commands to withdraw if start-up stack pattern cannot be matched.


Modules 4.5.0 (2020-04-07)
==========================

* Doc: fix typos and grammar mistakes on module, modulefile and
  Changes between versions documents. (contribution from Colin
  Marquardt)

* Doc: update cookbook recipes to highlight code of the Tcl scripts
  included. (contribution from Colin Marquardt)

* Doc: improve markup of module, modulefile and Changes between
  versions documents to enable references to module sub-commands,
  command line switches, environment variables and modulefile Tcl
  commands. (contribution from Colin Marquardt)

* Doc: alphabetically sort module sub-commands, command-line switches,
  environment variables and modulefile Tcl commands in module and
  modulefile documents.

* Introduce the "ml" command, a handy frontend to the "module"
  command. "ml" reduces the number of characters to type to trigger
  "module". With no argument "ml" is equivalent to "module list", "ml
  mod" corresponds to "module load mod" and "ml -mod" means "module
  unload mod". Multiple modules to either load or unload can be
  combined on a single command. "ml" accepts all command-line switches
  and sub-commands accepted by "module" command. "ml" command is
  defined by default. Its definition can be controlled at
  "./configure" time with "--enable-ml" option or later on with "ml"
  configuration option (which defines "MODULES_ML" environment
  variable when set).

* Fix module sub-command abbreviation match to ensure passed
  abbreviated form fully match sub-command, not only its minimal
  abbreviated form. As an example, "lod" or "loda" do not match
  anymore the "load" sub-command, "lo" or "loa" still do.

* Add the "-j"/"--json" command line switches to the "avail", "list",
  "savelist", "whatis" and "search" module sub-commands to render
  their output in JSON format. (fix issue #303)

* Script: remove need to build project management-specific tools
  ("mtreview", "mb", "mlprof" and "playdemo") prior using them.

* Script: gather all distributed and maintained scripts in a "script"
  directory at the root of the project repository tree.

* Install: provide Windows-specific batch files when "./configure"
  option "--enable-windows-support" is set. module command wrapper
  "module.cmd" is installed in "bindir" and initialization script
  "cmd.cmd" in "initdir". Those batch files are relocatable and expect
  "modulecmd.tcl" in "..\libexec" directory. (fix issue #272 with
  contribution from Jacques Raphanel)

* Install: add ml command wrapper "ml.cmd" and install it in "bindir"
  when "./configure" option "--enable-windows-support" is set.

* Install: introduce envml command wrapper "envml.cmd" for Windows
  "cmd" shell and install it in "bindir" when "./configure" option "--
  enable-windows-support" is set. (contribution from Jacques Raphanel)

* Doc: improve documentation portal index.

* Install: add "dist-win" target to Makefile in order to build a
  distribution zipball containing the required files to run Modules on
  a Windows platform. "INSTALL.bat" and "UNINSTALL.bat" Windows batch
  files are introduced and shipped in the zipball to automate
  installation and basic configuration of Modules on the Windows
  platform.

* Doc: update Installing Modules on Windows document to describe how
  to install Modules with newly provided Windows-specific distribution
  zipball.

* Install: enable build of Modules from "git archive" tarball or
  zipball exports (like download source archives automatically
  provided on GitHub project)

* Install: ship reStructuredText and MarkDown source documents at the
  root of Modules distribution tarball rather their built txt
  counterpart.

* Script: fix "createmodule.sh" script to correctly analyses
  environment when shell functions are found defined in it.

* Script: inhibit output generated by scripts evaluated by
  "createmodule.sh" and "createmodule.py" to ensure these outputs will
  not get in the way when analyzing the environment changes. (fix
  issue #309)

* Correctly handle symbolic version target including a whitespace in
  their name.

* Testsuite: output test error details whatever the testsuite run
  verbose mode.

* Install: adapt configure script and Makefile to detect "python"
  command location and set it as shebang for "createmodule.py" and
  "gitlog2changelog.py". If "python" command is not found, "python3"
  then "python2" are searched.

* Install: enable to pass a specific Python interpreter command name
  or location at configure step with "--with-python" option. Specified
  command name or location should be found on build system only if
  building from git repository.

* Install: build "createmodule.py" script and install it in "bindir".

* Install: update RPM spec file to explicitly define Python
  interpreter location.

* Script: fix "createmodule.py" script for Python3 (fix issue #315
  with contribution from Armin Wehrfritz)

* Lift Perl variable strictness when defining "_mlstatus" variable in
  case "modulecmd.tcl" output is directly evaluated without use of the
  "module" sub-routine in Perl script. (with contribution from Andrey
  Maslennikov)

* Script: fix path de-duplication in "createmodule.sh". (fix issue
  #316)

* Doc: add *Handling Compiler and other Package Dependencies* cookbook
  recipe, which discusses various strategies for creating modulefiles
  for packages with multiple builds depending on previously loaded
  compiler, MPI libraries, etc. (contribution from Tom Payerle)

* Init: test availability of "compopt" Bash builtin prior using it in
  Bash completion script to avoid error with versions of this shell
  older than 4.0. (fix issue #318)

* Install: adapt configure step to detect if "sed" option "-E" is
  supported and fallback to "-r" otherwise in shell completion
  scripts. (fix issue #317)

* Add support for the "NO_COLOR" environment variable (https://no-
  color.org/) which when set (regardless of its value) prevents the
  addition of ANSI color. When set, "NO_COLOR" prevails over
  "CLICOLOR" and "CLICOLOR_FORCE" environment variables.
  "MODULES_COLOR" overrides these three variables. (fix issue #310)

* Script: when analyzing environment variable changes in
  "createmodule.sh" applied by shell script passed as argument,
  produce a "setenv" modulefile statement for any variable found set
  prior script evaluation and for which value is completely changed
  after script evaluation. (fix issue #320)

* When an error message is composed of multiple lines, render it in
  the same way whether it is part of a block message or not: lines
  after the first one are prepended with a 2-space padding. As a
  result error messages appear clearly separated from each other.

* Append to the error message the error stack trace when a general
  unknown error occurs in "modulecmd.tcl" and provide a link to
  encourage users to report such error to the GitHub project.

* Add to the error message the error stack trace for errors occurring
  during site-specific configuration evaluation. Error stack is
  expunged from the "modulecmd.tcl" internals to only report
  information relevant to site-specific configuration file.

* When an error occurs during the evaluation of a modulefile or a
  modulerc, report associated error stack trace expunged from
  "modulecmd.tcl" internal references to only output useful
  information for users.

* GitHub: add issue templates to guide people submitting a bug report
  or a feature request.

* Doc: provide a link toward issues that have been fixed between
  versions 3.2 and 4.0 in Changes between versions document.

* Script: introduce "envml.cmd" script for Windows platform providing
  similar behavior than "envml" Bash script. (contribution from
  Jacques Raphanel)

* Init: add Bash shell completion for the "ml" command. (contribution
  from Adrien Cotte)

* Fix Fish shell stderr redirection for newer Fish versions. (fix
  issue #325)

* Correctly handle modulefiles and modulepaths containing a space
  character in their name whether they are used from the command-line,
  in collections, within modulefiles or from loaded environment
  definitions.

* Doc: add *Default and latest version specifiers* design note.

* An "avail" search over a symbolic version targeting a directory now
  correctly returns the special modules (alias and virtual module)
  lying in this directory. (fix issue #327)

* "whatis" and "paths" searches only return special modules (symbolic
  version, alias and virtual modules) that fully match search query,
  not those that partially match it. (fix issue #328)

* alias and virtual module whose name mention a directory that does
  not exists are correctly handled. (fix issue #168)

* Hide special modules (aliases, symbolic versions and virtual
  modules) whose version name starts with a dot character (".") from
  "avail", "whatis" and "paths" searches if their query does not fully
  match special module name. (fix issue #329)

* Filter-out from the output of the "aliases" sub-command all hidden
  aliases, symbolic versions or hidden modules targeted by a non-
  hidden symbolic version. (fix issue #330)

* Enable resolution of default module in module sub-directory when
  this default symbol targets a hidden directory (whose name starts
  with a dot character). (fix issue #331)

* Doc: clarify hidden module location in modulefile man page.

* Install: define "LD_PRELOAD" as quarantine var along with
  "LD_LIBRARY_PATH" in RPM specfile.

* When "implicit_default" and "advanced_version_spec" configuration
  are enabled, automatically define a "default" and "latest" symbolic
  version for each module name (at each module depth for deep modules)
  if those version names does not already exist. (fix issue #210)

* Once a module is loaded, the automatically defined symbols
  associated to it are recorded in loaded environment in the
  "MODULES_LMALTNAME" environment variable. They are distinguished
  from the other alternative names applying to the module by a "as|"
  prefix, which qualifies their *auto symbol* type.

* When an advanced version specifier list contains symbolic version
  references, fix resolving to honor default version if part of the
  specified list. (fix issue #334)


Modules 4.4.1 (2020-01-03)
==========================

* Fix error and warning messages relative to dependency management to
  enclose dependency specification in single quotes to clearly
  distinguish specification from each other.

* Skip output of module loading message if module is already loaded.

* Doc: add demonstration material played at SC19 to promote the new
  features of Modules.

* Contrib: add "playdemo" script to play recorded demonstration cast.

* Doc: add a web anchor to each modulefile Tcl command, module sub-
  command and module environment variable documentation.

* Install: update RPM spec file to enable build on "el8".

* Doc: fix RST syntax for bullet lists in design docs. (fix issue
  #306)

* In case "module avail" query does not match a directory but only its
  contained elements (for instance "module av mod/7" matches "mod/7.1"
  and "mod/7.2" but not "mod/"), fix query processing to correctly
  return latest or default element in case "--latest" or "--default"
  flags are set.

* In case a "module avail" query performed in a no-indepth mode with "
  --latest" or "--default" flags either enabled or disabled, fix query
  processing to return directory elements if they are part of result.

* When a "module avail" query performed in no-indepth mode targets a
  virtual module, fix result to filter-out the directory holding the
  virtual module from result.

* Fix "module avail --default" queries when modulefile default version
  does not match query: select latest version from modulefiles
  matching query unless "implicit_default" configuration is disabled
  in which case no default version is returned.

* Improve highlighting of module "avail" and "whatis" search result by
  coloring module names matching search query expressed with the
  advanced version specifiers. "name@1,3" or "name@1:3" queries now
  highlight "name/1" and "name/3" strings found in search result.

* Contrib: add the "mlprof" script which wraps "modulecmd.tcl" to
  collect profiling information on its execution.

* Contrib: adapt "mb" script to profile "modulecmd.tcl" run tests
  rather bench them when "profile" argument is passed to the script.

* Improve overall performances of module names and versions comparison
  by introducing optimized procedures and caching in memory module
  search results.


Modules 4.4.0 (2019-11-17)
==========================

* Doc: add *Return file basename on module-info name for full path
  modulefile* recipe to cookbook. (fix issue #297)

* Rework internal handling of configuration options to gather all
  option definitions in a global array and use the same initialization
  and retrieval procedure, named "getConf", for all these options.

* Add the "setConf", "unsetConf" and "lappendConf" procedures to
  provide unified ways to set the value of configuration option. These
  procedures should be used in site configuration files to override
  configuration option value instead of directly setting corresponding
  option variable as it was done in previous Modules releases.

* Add the ability to match module specification in a case insensitive
  manner. Default case sensitiveness behavior is set at "./configure"
  time with the "--with-icase" option. It could be superseded with the
  "MODULES_ICASE" environment variable, that could be set with
  "config" module sub-command through the "icase" option. Command-line
  switch "--icase" ("-i") enables to supersede defined case
  sensitiveness configuration. (fix issue #212 with contribution from
  Eric Deveaud)

* Introduce the extended default mechanism, to help selecting a module
  when only the first numbers in its version are specified. Starting
  portion of the version, part separated from the rest of the version
  string by a "." character, will get matched to the appropriate
  complete version name. In case multiple versions match partial
  version specified and only one module should be returned, default
  version (implicit or explicit) among matches is returned. In case
  "implicit_default" option is disabled and no explicit default is
  found among matches, an error is returned. This mechanism is enabled
  through a new configuration option named "extended_default" (which
  defines "MODULES_EXTENDED_DEFAULT" environment variable when set).
  It may be enabled by default in "modulecmd.tcl" script with option "
  --enable-extended-default" passed to the "./configure" script.

* Introduce the advanced module version specifiers mechanism to
  specify finer constraints on module version. This new feature
  enables to filter the module selection to a given version list or
  range by specifying after the module name a version constraint
  prefixed by the "@" character. It leverages the version specifier
  syntax of the Spack package manager. A single version can be
  specified with the "@version" syntax, a list of versions with
  "@version1,version2,...", a greater than or equal to range with
  "@version1:" syntax, a less than or equal to range with "@:version2"
  and an in between or equal to range with "@version1:version2"
  syntax. In case "implicit_default" option is disabled and no
  explicit default is found among version specifier matches, an error
  is returned. This mechanism is enabled through a new configuration
  option named "advanced_version_spec" (which  defines
  "MODULES_ADVANCED_VERSION_SPEC" environment variable when set). It
  may be enabled by default in "modulecmd.tcl" script with option "--
  enable-advanced-version-spec" passed to the "./configure" script.

* Conflict defined with a generic module name or an advanced version
  specifier may match multiple loaded modules (generally in case
  multiple loaded modules share same root name). Loaded environment
  analysis has been fixed to bind conflict to all loaded modules
  matching it. As a result the *Dependent Reload* mechanism is not
  triggered when one loaded module matching conflict is removed if
  another loaded module still match the conflict.

* Doc: add *Module selection contexts*, *Insensitive case*, *Extended
  default* and *Advanced module version specifiers* design notes.

* Make "MODULESHOME" environment variable controllable through the
  "config" sub-command with "home" configuration option. A "--with-
  moduleshome" argument is also added to the ./configure script to set
  specific default value for this option at installation time. (fix
  issue #292)


Modules 4.3.1 (2019-09-21)
==========================

* Contrib: add "mb" script to bench Modules versions.

* Correct "modulecmd.tcl" script startup to correctly report error in
  case Tcl extension library fails to load. (fix issue #284)

* Install: fix typo on "CFLAGS" definition in "lib/Makefile". (fix
  issue #287 with contribution from Felix Neumärker)

* Remove useless code in Modules Tcl extension library

* Make URLs in README correctly rendered in HTML. (contribution from
  Per Persson)

* Doc: clarify modulefile evaluation modes in modulefile.4 man page.
  (fix issue #289)

* When looking at the closest match among loaded modules when
  switching module with just a single module argument specified, load
  the information on the currently set environment to get the
  alternative names of loaded modules prior to look at closest module
  match. (fix issue #290)

* Doc: describe the way to determine the site-specific configuration
  script location in cookbook recipes implying the installation of
  such a file. (fix issue #266)

* Doc: add *Log module command* recipe to cookbook. (fix issue #283)

* Doc: add *Expose procedures and variables to modulefiles* recipe to
  cookbook.

* Doc: add *Make defined modulepaths persist over sudo* recipe to
  cookbook.

* Doc: add *Ensure user fully qualify the modules they use* recipe to
  cookbook.

* Introduce the "wa_277" configuration option to workaround an issue
  with Tcsh history mechanism. Default "module" alias definition for
  Tcsh hits an issue with shell history mechanism: erroneous history
  entries are recorded each time the "module" command is called. When
  "wa_277" option is enabled (which sets the "MODULES_WA_277"
  environment variable to *1*), an alternative module alias is defined
  which fixes the history mechanism issue. However the alternative
  definition of the module alias weakens shell evaluation of the code
  produced by modulefiles. Characters with special meaning for Tcsh
  shell (like *{* and *}*) may not be used anymore in shell alias
  definition elsewhere the evaluation of the code produced by
  modulefiles will return a syntax error. (fix issue #277)

* Doc: add *Tips for Code Reuse in Modulefiles* recipe to cookbook.
  (contribution from Tom Payerle)

* Fix the "whatis" and "paths" sub-command results for module symbolic
  versions targeting a directory when "implicit_default" configuration
  option is disabled. No error is returned and same result is now
  obtained whether the symbolic name or its target is used as argument
  for those two sub-commands. (fix issue #294)

* Fix the "whatis" and "paths" sub-command results for module aliases
  targeting a directory when "implicit_default" configuration option
  is disabled. No error is returned and same result is now obtained
  whether the alias name or its target is used as argument for those
  two sub-commands. (fix issue #295)

* Rework all the ternary operator expressions in "modulecmd.tcl" that
  may result in a *nan* value (whatever the case used to write this
  string) as the "expr" Tcl command raises an error when it returns
  such a value, which breaks Modules as soon as a modulefile, an alias
  or a symbolic version is named *nan*. (fix issue #296)


Modules 4.3.0 (2019-07-26)
==========================

* Introduce Vim addon files to highlight the modulefile syntax.
  Installation of these files, which is enabled by default, is
  controlled by the "--enable-vim-addons" and "--vimdatadir" configure
  options. (contribution from Felix Neumärker)

* If modulefile is fully read, cache the content read and the file
  header computed to avoid another file read if the same modulefile
  need to be read multiple times.

* Except for path, paths, list, avail and aliases module commands
  always fully read a modulefile whether its full content is needed or
  just its header to verify its validity. Proceed this way to only
  read file once on commands that first just check modulefile validity
  then read again valid files to get their full content.

* Introduce Modules Tcl extension library (written in C) to extend Tcl
  language in order to provide more optimized I/O commands to read a
  file or a directory content than native Tcl commands do.

* Install: add "--libdir", "--enable-libtclenvmodules", "--with-tcl"
  and "--with-tclinclude" options to configure script to control
  libtclenvmodules build and installation.

* When an error is caught during modulecmd.tcl first initialization
  steps, ensure the error report facility is initialized to render
  error message.

* When looking for modulefiles in enabled modulepaths, take
  ".modulerc" file found at the root of a modulepath directory into
  account. Which means these rc files are now evaluated like global rc
  files and can be used to define module aliases targeting modulefiles
  stored in the underlying file tree.

* Correctly get available default (-d) and latest (-L) version whether
  search pattern is passed with an ending forward slash character or
  not or if it contains a "*" wildcard character.

* Append a forward slash character to any directory result of an avail
  command to better distinguish these directories from regular files.

* Introduce the ability to control whether "avail" command search
  results should recursively include or not modulefiles from
  directories matching search query by use of the "--indepth" and "--
  no-indepth" command-line switches or the environment variable
  "MODULES_AVAIL_INDEPTH". Default behavior is set at the
  "./configure" time with the "--enable-avail-indepth" and "--disable-
  avail-indepth" switches. (fix issue #150)

* Update "bash", "fish" and "zsh" completion scripts to propose
  available modulefiles in the no in depth mode.

* Add the ability to graphically enhance some part of the produced
  output to improve readability by the use of the "--color" command-
  line switch or the "MODULES_COLOR" environment variable. Both accept
  the following values: "never", "auto" and "always". When color mode
  is set to "auto", output is colored if stderr is attached to a
  terminal. Default color mode could be controlled at configure time
  with the "--enable-color" and the "--disable-color" option, which
  respectively correspond to the "auto" and "never" color mode.

* Control the color to apply to each element with the "MODULES_COLORS"
  environment variable or the "--with-dark-background-colors" and "--
  with-light-background-colors" configure options. These variable and
  options take as value a colon-separated list in the same fashion
  "LS_COLORS" does. In this list, each element that should be
  highlighted is associated to a Select Graphic Rendition (SGR) code.

* Inform Modules of the terminal background color with the
  "MODULES_TERM_BACKGROUND" environment variable or the "--with-
  terminal-background" configure option, which helps to determine if
  either the dark or light background colors should be used to color
  output in case no specific color set is defined with the
  "MODULES_COLORS".

* Color prefix tag of debug, error, warning, module error and info
  messages.

* Highlight the modulefile or collection name when reporting messages
  for a an action made over this modulefile or collection.

* Color the modulepaths reported on a "use" command.

* Highlight title of separator lines or column name of table header.

* Color modulepaths, directories, aliases and symbols reported by the
  "avail", "aliases", "list", "whatis" and "search" commands.

* When color mode is enabled and module aliases are colored, do not
  associate them a "@" tag as the color already distinguish them from
  regular modulefile.

* When color mode is enabled and a Select Graphic Rendition (SGR) code
  is set for the "default" modulefile symbol, apply this SGR code to
  the modulefile name instead of associating it the "default" symbol
  tag.

* Highlight matched module search query string among "avail", "whatis"
  and "search" command results.

* Highlight the modulefile and collection full path name on "display",
  "help", "test" and "saveshow" command reports.

* Color modulefile Tcl commands set in a modulefile on a "display"
  command report.

* Color module commands set in a collection on a "saveshow" command
  report.

* Re-introduce "clear" sub-command. (fix issue #203)

* Leverage "--force" command-line switch on "clear" sub-command to
  skip confirmation dialog. (fix issue #268)

* Init: improve readability of variable definition operations by
  writing one definition operation per line rather having multiple
  commands on a single line like "VAR=val; export VAR". (fix issue
  #225)

* Add the ability to define a site-specific configuration file with an
  environment variable: "MODULES_SITECONFIG". When set, the script
  file pointed by the variable is sourced (if readable) after the
  site-specific configuration file initially defined in
  "modulecmd.tcl". (contribution from Ben Bowers, fix issue #234)

* Doc: add description in the module.1 man page of "MODULERCFILE" in
  the environment section and "siteconfig.tcl" in the files section.

* Install: provide at installation time a bare site-specific
  configuration script in designated "etcdir" if no pre-existing
  "siteconfig.tcl" file is found at designated location.

* Introduce the "config" sub-command to get and set "modulecmd.tcl"
  options and to report its current state.

* Contrib: update "createmodule.py" script to support execution from
  the *cmd* shell. (contribution from Jacques Raphanel, fix issue
  #270)

* Add the ability to configure when unloading a module and multiple
  loaded modules match request if firstly loaded module should be
  chosen or lastly loaded module. Configure option "--with-unload-
  match-order" defines this setting which can be superseded with the
  "MODULES_UNLOAD_MATCH_ORDER" environment variable. This variable can
  be set with the option "unload_match_order" on the "config" sub-
  command. By default, lastly loaded module is selected. It is
  recommended to keep this behavior when the modulefiles used express
  dependencies between each other.

* Add the ability to configure whether an implicit default version
  should be defined for modules with no default version explicitly
  defined. When enabled, which stays the default behavior, a module
  version is automatically selected (latest one) when the generic name
  of the module is passed. When implicit default selection is
  disabled, the name of modules to evaluate should be fully qualified
  elsewhere an error is returned. This option is set at "./configure"
  time with the "--enable-implicit-default" and "--disable-implicit-
  default" options. It could be superseded with the
  "MODULES_IMPLICIT_DEFAULT" environment variable, that could be set
  with "config" module sub-command through the "implicit_default"
  option.

* Install: add to the configure script the "--with-locked-configs"
  option to ignore environment variable superseding of Modules
  configurations defined in "modulecmd.tcl" script. Lockable
  configuration option are "extra_siteconfig" and "implicit_default".
  Currently locked options are reported through the "locked_configs"
  option on the "config" sub-command.

* Introduce the ability to control the module search match. Search
  query string should match module name start or any part of module
  fully qualified name. Default search match behavior is set at
  "./configure" time with the "--with-search-match" option. It could
  be superseded with the "MODULES_SEARCH_MATCH" environment variable,
  that could be set with "config" module sub-command through the
  "search_match" option. Command-line switches "--starts-with" ("-S")
  and "--contains" ("-C") for "avail" module sub-command enable to
  supersede defined search match configuration.

* Introduce the ability not to set the shell startup file that ensure
  "module" command is defined once shell has been initialized. Setting
  shell startup file currently means defining "ENV" and "BASH_ENV"
  environment variables to the Modules bourne shell initialization
  script. "./configure" options "--enable-set-shell-startup" and "--
  disable-set-shell-startup" define if shell startup should be set or
  not by default. It could be superseded with the
  "MODULES_SET_SHELL_STARTUP" environment variable, that could be set
  with "config" module sub-command through the "set_shell_startup"
  option.

* Cookbook: add the *test-modulefiles* recipe. (fix issue #182 with
  contribution from Colin Marquardt)

* Fix location of global RC file to "@etcdir@/rc" instead of
  "@prefix@/etc/rc" to cope with "@etcdir@" specific setup ("@etcdir@"
  defaults to "@prefix@/etc").

* Take into account Modules initialization configurations found in
  "etc" directory if they exist rather in "init" directory. If
  "initrc" configuration file is found in "etcdir" then it is
  preferred over "modulerc" file in "initdir". Following the same
  trend, "modulespath" configuration file is found in "etcdir" then it
  is preferred over ".modulespath" file in "initdir".

* Introduce the ability to install the Modules initialization
  configuration files in the "etcdir" rather than in the "initdir". A
  new configure option is introduced for this task: "--with-initconf-
  in". Accepted values for this option are: "etcdir" or "initdir"
  (default).

* Add the "--enable-modulespath" configure option, which is an alias
  for the "--enable-dotmodulespath" option as ".modulespath"
  configuration file is named "modulespath" when installed in
  "etcdic".

* Install: update RPM spec file to disable "set_shell_startup" option
  by default, set "/etc/environment-modules" as configuration
  directory and store Modules initialization configuration files in
  it.

* Report an error when a module load or unload evaluation aborts due
  to the use of the "break" or "exit" modulefile commands. This error
  notification clarifies that module evaluation failed. (fix issue
  #267)

* Remove the message block display output for the "reload", "purge"
  and "restore" sub-commands to preserve this output style for
  modulefile evaluation modes (load, unload and switch) and thus
  clarify understanding.

* When unloading a module that contains a "module load" or "module
  switch" modulefile command, inhibit the unload performed of the
  useless requirement when auto_handling mode is disabled if currently
  performing a "purge", "reload" or "restore" sub-command. As the
  unload sequence is determined and managed from these top commands.

* Add ability to control module command message verbosity with
  configuration option. Introduced verbosity levels from the least to
  the most verbose are "silent", "concise", "normal", "verbose" and
  "debug". This option could be set at "./configure" time with "--
  with-verbosity" option. It could be superseded with the
  "MODULES_VERBOSITY" environment variable, that could be set with
  "config" module sub-command through the "verbosity" option. Silent,
  verbose and debug verbosity modes can be set at the command-line
  level respectively with "--silent"/"-s", "--verbose"/"-v" and "--
  debug"/"-D" command-line switches. (fix issue #204)

* When verbosity level is "normal" or higher, reports every module
  loads or unloads performed to "restore" a collection or "source" a
  scriptfile, even if there is no specific message to output for these
  module evaluations. Clarifies what module evaluations have been
  triggered by these sub-commands.

* Also honor the "CLICOLOR" and "CLICOLOR_FORCE" environment variables
  to define color mode. (fix issue #279)


Modules 4.2.5 (2019-07-08)
==========================

* Correctly escape "?" character in shell alias. (fix issue #275)

* When resolving the enabled list of modulepaths, ensure resolved path
  entries are unique. (fix issue #274)

* Right trim '#' characters from the fetched modulefile magic cookie
  string to ensure a correct compatibility version comparison. Useful
  when modulefile first line is equal to "#%Module4.2##############".

* Fix argument parsing for the "append-path", "prepend-path" and
  "remove-path" modulefile commands to consider every arguments found
  after the variable name as variable values and not command option
  even if argument starts with "-" character. (fix issue #278)

* Fix automatic loading of modulefiles when multiple module names are
  set on a single "module load" modulefile command. When auto_handling
  mode was disabled, the load of not loaded modules was not achieved
  as soon as some modules on this list were already loaded. (fix issue
  #281)


Modules 4.2.4 (2019-04-26)
==========================

* Better track each module evaluation and the context associated to it
  in order to report a more accurate information on the additional
  modules loaded or unloaded when proceeding the main evaluation
  request. (fix issue #244, #245, #246, #247 and #248)

* Doc: preserve quotes and dashes when making HTML docs. (fix issue
  #250 with contribution from Riccardo Coccioli)

* Fix hanging "list" sub-command when terminal width is equal to the
  single column text width to be printed. (contribution from Jesper
  Dahlberg)

* During an additional evaluation triggered by an automated module
  handling mechanism, ensure warning and error messages are reported
  under the message block of the main evaluation. (fix issue #252)

* During the unload of a module when the automated module handling
  mode is disabled, report a warning message for each unload of a
  useless requirement that fails as done when the automated module
  handling mode is enabled. (fix issue #253)

* When multiple modules are listed on a "prereq" command, drop the
  output of those modules that fails to load (by the *Requirement
  Load* automated mechanism) to only keep the output of the module
  whose load succeed. (fix issue #254)

* Fix "switch" sub-command when the switched-off module cannot be
  unloaded when other loaded modules depend on it. Whole switch
  process is failed and no load of the switched-on module is
  attempted. (fix issue #251)

* When switching modules, report failure of switched-off module unload
  or switched-on module load under the message block of the switch
  action. A failed switched-off module unload is reported as an error,
  as it aborts the switch evaluation, whereas a failed switched-on
  module load is reported as a warning. (fix issue #255)

* When a module requirement is seen missing but the load of this
  module was attempted, report a more specific error or warning
  message to let user understand that the load of the requirement was
  attempted but failed. (fix issue #257)

* When loading a module, report any missing requirement on the message
  reporting block corresponding to this module load. This warning or
  error message comes in addition to the eventual *Requirement Load*
  message reported under the message block of the main evaluation.
  (fix issue #258)

* When unloading a module which has some dependent module still
  loaded, produce a more specific error or warning message if an
  evaluation of these dependent modules has been realized or if the
  unload of the required module is forced. (fix issue #259)

* When a conflicting module is seen loaded but the unload of this
  module was attempted, report a *Conflict Unload* error or warning
  message toward the main evaluation message block. (fix issue #261)

* When loading a module, report any loaded conflict on the message
  reporting block corresponding to this module load. This warning or
  error message comes in addition to the eventual *Conflict Unload*
  message reported under the message block of the main evaluation.
  (fix issue #261)

* Correctly report loading state of conflicting module. (fix issue
  #262)

* Adapt warning, error and info messages relative to the *Dependent
  Reload* mechanism to distinguish the unload phase from the load
  (reload) phase of this mechanism. In the automated module handling
  summary report, unloaded modules via this mechanism are reported in
  the *Unloading dependent* list and modules reloaded afterward are
  reported against the *Reloading dependent* list. (fix issue #263)

* When the automated module handling mode is disabled, do not attempt
  to load a requirement expressed in a modulefile with a "module load"
  command, if this requirement is already loaded or loading.

* Skip load or unload evaluation of a module whose respectively load
  or unload was already attempted but failed. If this second
  evaluation attempt occurs within the same main evaluation frame.
  (fix issue #264)

* When reloading modules through the *Dependent Reload* automated
  mechanism, prevent modules to automatically load of other modules
  with the "module load" modulefile command, as it is done for the
  "prereq" command. (fix issue #265)

* Raise an error when an invalid option is set on "append-path",
  "prepend-path" or "remove-path" modulefile command. (fix issue #249)

* Zsh initializes by default the "MANPATH" environment variable to an
  empty value when it starts. To preserve "manpath" system
  configuration even after addition to this variable by modulefiles,
  set "MANPATH" variable to ":" if found empty. (improve fix for issue
  #224)

* Doc: provide a short installation guideline in README file. (fix
  issue #230)


Modules 4.2.3 (2019-03-23)
==========================

* Add all the module dependency-related internal information to those
  saved prior a modulefile evaluation in order to correctly restore
  internal state in case modulefile evaluation fails.

* Init: in shell initialization scripts, initialize "MANPATH" if not
  set with a value that preserves "manpath" system configuration even
  after addition of paths to this variable by modulefiles. (fix
  issue#224)

* Enable to define an entire path entry to the "MODULEPATH" variable
  which corresponds to a variable reference only. (fix issue#223)

* Cookbook: add the *modulefiles-in-git* recipe. (contribution from
  Scott Johnson)

* When "module switch" commands are found in modulefiles, track
  switched-off modulefile as a conflict and switched-to modulefile as
  a requirement to apply same behaviors than for "module load" and
  "module unload" commands in modulefiles. If "module switch" has only
  one argument, do not define a conflict toward switched-off
  modulefile. *CAUTION: it is not recommended to use module switch
  command in modulefiles*. (fix issue#229)

* When unloading a module, revert "module switch" commands found in
  modulefile: switched-on module is converted to a "module unload",
  like for "module load" command. Nothing is done for switched-off
  module, like for "module unload" command. (fix issue#226)

* For default element in a modulefile directory which is a module
  alias that points to a modulefile, when this modulefile is loaded,
  it receives as alternative names the eventual module aliases set on
  the distant directory holding the alias pointing to it. (fix
  issue#231)

* When unloading a module that contains "module load" or "module
  switch" commands in its modulefile, select for unload the
  automatically loaded requirement module which has been loaded prior
  its dependent. (fix issue#232)

* Doc: describe Emacs settings useful for adhering to coding
  conventions in CONTRIBUTING guide. (fix issue #233 with contribution
  from Ben Bowers)

* When looking for a loaded or loading dependency requirement, select
  among the eventual multiple candidates the closest match to the
  dependent module.

* During the unload of a module, if the unload of one of its dependent
  (by the *Dependent Unload* mechanism) fails, abort the whole unload
  process. Exception made if the force mode is enabled. In this case
  failing module stays loaded and the *Dependent Unload* mechanism
  continues with next module to unload.

* During the unload of a module, if the unload of one of its useless
  requirements (by the *Useless Requirement Unload* mechanism) fails,
  keep the requirements of this failing module loaded. Such error is
  reported as a warning and it does not stop the whole unload process.
  (fix issue#240)

* During the load or the unload of a module, if the unload of one of
  its dependent (by the *Dependent Reload* mechanism) fails, abort the
  whole unload or load process. Exception made if the force mode is
  enabled. In this case failing module stays loaded and *Dependent
  Reload* mechanism continues with next module to unload. This failing
  module is removed from the *Dependent Reload* list, so it will not
  take part of the load phrase of the mechanism. (fix issue#239)

* During the load or the unload of a module, if the load of one of its
  dependent (by the *Dependent Reload* mechanism) fails, abort the
  whole unload or load process. Exception made if the force mode is
  enabled. In this case failing module stays loaded and *Dependent
  Reload* mechanism continues with next module to load. When the
  mechanism is applied during a "switch" command, force mode is
  enabled by default on the load phase. (fix issue#241)

* When reloading all loaded modules with the "reload" sub-command, if
  one reloading module fails to unload or load, abort the whole reload
  process to preserve environment sanity. (fix issue#237)

* During the unload of a module when the automated module handling
  mode is disabled and this module declares its requirements with the
  "module load" modulefile command. If the unload of one of its
  useless requirements (by the *Useless Requirement Unload* mechanism)
  fails, whole unload process is not aborted and continue with next
  module to unload. (fix issue#238)

* Contrib: add "mtreview" utility script that analyzes test suite log
  file to compare actual and expected output of failed test. "mt" does
  not output the full test suite logs anymore but only the information
  produced by "mtreview" on failed tests.

* Install: exclude Continuous Integration configurations from dist
  tarballs.


Modules 4.2.2 (2019-02-17)
==========================

* Correct the *Dependent Unload* mechanism when it triggers the unload
  of 2 modules making together a requirement from another module. This
  module is now also added to the dependent modules to unload.

* Doc: add a cookbook section in the documentation and port there the
  3 pre-existing recipes: *inhibit-report-info*, *top-priority-values*
  and *unload-firstly-loaded*.

* Doc: add a CONTRIBUTING guide.

* Doc: fix a typo on the Python initialization example in module man
  page.

* Doc: add a FAQ entry to describe the use of module from Makefile.
  (with contribution from Robert McLay)

* Trim any white-space, newline or ";" characters at the beginning or
  end of the function body passed to set-function modulefile command.

* Init: add recognition of the "--auto", "--no-auto" and "--force"
  command-line switches in fish shell completion script.

* Init: add recognition of the "--auto", "--no-auto", "--force", "--
  paginate" and "--no-pager" command-line switches in zsh shell
  completion script.

* When the load of a modulefile is asked but a conflict is registered
  against this modulefile by an already loaded module, the load
  evaluation is now performed and the conflict is checked after this
  evaluation. If the conflict is still there, this evaluation (and the
  evaluation of its requirements) is rolled back. (fix issue#216)

* Init: fix "_module_not_yet_loaded" alias in tcsh completion script
  to handle situation when "noclobber" variable is set. Also ensure
  actual "rm" command is called and not an alias. (fix issue#219)

* Fix warning message when the load of a modulefile is forced over a
  reflexive conflict (message was reported twice).

* When looking at the dependency of a loaded module, only consider
  requirement loaded before dependent module (holding a prior position
  in the loaded module list) as valid. Those loaded after dependent
  module are considered as an unmet dependency thus they are not
  taking part in the *Dependent Unload*, the *Useless Requirement
  Unload* and the *Dependent Reload* mechanisms.


Modules 4.2.1 (2018-11-11)
==========================

* Cookbook: add the *inhibit-report-info* recipe.

* Cookbook: port *unload-firstly-loaded* and *top-priority-values*
  recipes to v4.2.

* Init: fix listing of loaded modules for *fish* and *tcsh* shell
  completions.

* Init: fix saved collection listing when no collection found for
  *bash*, *zsh*, *tcsh* and *fish* shell completions.

* Adapt "system" modulefile Tcl command to execute the command passed
  as argument through shell, like it is performed on compatibility
  version. (fix issue#205)

* Correctly filter modulefile search memory cache entries when using a
  full search result to search later on a specific modulefile.

* Prefix debug messages by information on the current modulefile or
  modulerc interpreter if any.

* Init: fix listing of loaded modules on unload and switch sub-
  commands for *bash* shell completion.

* Refrain "module unload" modulefile command from unloading a module
  required by another loading module.

* Enable "is-loaded" modulefile Tcl command in modulerc interpretation
  context, like done on compatibility version. (fix issue#207)

* Check a required module is not already loading before attempting to
  load it. Helps to handle cyclic dependencies.

* Compute loaded modules requirement dependency relations without
  cycle and consider the module closing the cycle in a constraint
  violation state to avoid reloading loops on the *Dependent Reload*
  mechanism.

* Safely unset dependency reference when computing dependency
  relations as some dependencies expressed may target same module.

* Ensure a loaded module matching multiple entries of a same *or*
  "prereq" will just be considered as one module matching this
  requirement.

* Init: quote prompt in *csh* and *tcsh* script with ":q" rather
  double quotes to accommodate prompts with embedded newlines. (fix
  issue#209 with contribution from Satya Mishra)

* Init: skip shell environment alteration if "autoinit" command fails.
  (fix issue#208)

* Reword path-like variable element counter reference handling to
  simply ignore the counter values not coherent with the content of
  related path-like variable. (fix issue#206)


Modules 4.2.0 (2018-10-18)
==========================

* Add "chdir" and "puts" environment settings to the per-modulefile
  evaluation saved context. So previous values of these settings are
  restored in case of evaluation failure.

* Fix save and restore of "x-resource" environment settings on the
  per-modulefile evaluation context.

* Use the correct warning procedure to report the full reference
  counter inconsistency message (so this message is fully inhibited
  during global "whatis" evaluations).

* Make "append-path", "prepend-path", "remove-path" and "unsetenv"
  commands alter "env" Tcl global array during "display", "help",
  "test" or "whatis" evaluation modes. Thus an invalid argument passed
  to these commands will now raise error on these modes. (see
  Environment variable change through modulefile evaluation context
  section in MIGRATING document)

* On "whatis" mode, "append-path", "prepend-path", "remove-path",
  "setenv" and "unsetenv" commands initialize variables if undefined
  but do not set them to their accurate value for performance concern.

* Clear value instead of unsetting it during an unload mode evaluation
  of "setenv" or "*-path" commands to avoid breaking later reference
  to the variable in modulefile.

* Make "getenv" command returns value on "help", "test" or "whatis"
  evaluation modes. (fix issue#188)

* Add an argument to the "getenv" command to return the value of this
  argument if the queried variable is undefined.

* Use a different modulefile interpreter for each evaluation mode.

* Adapt the procedure called for each modulefile command depending on
  the evaluation mode to adapt behavior of these commands to the
  module command currently running.

* Report calling name and arguments for modulefile commands on
  "display" mode. For the commands evaluated during this mode, trigger
  this report at the end of the evaluation.

* Inhibit "chdir", "conflict", "module", "module-log", "module-trace",
  "module-user", "module-verbosity", "prereq", "set-alias", "system",
  "unset-alias", "x-resource" commands on "help", "test" and "whatis"
  evaluation modes.

* Ignore "chdir", "module", "module-trace", "module-verbosity",
  "module-user" and "module-log" commands found during modulerc
  evaluation.

* Correctly restore an empty string value on sub-interpreter global
  variables when sanitizing this interpreter between two
  modulefile/modulerc evaluations.

* Cache in memory results of a modulefile search to reuse it in case
  of rerun instead of re-walking the filesystem.

* Evaluate global rc files once module sub-command is known and
  registered, so it can be queried during their evaluation.

* Rename "_moduleraw" shell function in "_module_raw" to use a common
  "_module_" prefix for all module-related internal shell functions.

* Install: add "--enable-append-binpath" and "--enable-append-manpath"
  configure options to append rather prepend the bin or man directory
  when adding them to the relative environment variable.

* Doc: clarify documentation for module usage on scripting language
  like Perl or Python to mention that arguments to the "module"
  function should be passed as list and not as a single string.

* When interpreting a "setenv" modulefile order during an unload
  evaluation, variable is still set to be unset in generated shell
  code but it is set to the value defined on the "setenv" order in the
  interpreter context instead of being cleared.

* Register the conflicts defined by loaded modules in the environment
  (variable "MODULES_LMCONFLICT") and ensure they keep satisfied. (see
  Modulefile conflict constraints consistency section in MIGRATING
  document)

* Register the prereqs defined by loaded modules in the environment
  (variable "MODULES_LMPREREQ") and ensure they keep satisfied. (see
  Modulefile prereq constraints consistency section in MIGRATING
  document)

* Introduce the automated module handling mode, which consists in
  additional actions triggered when loading or unloading a modulefile
  to satisfy the dependency constraints it declares. Those actions are
  when loading a modulefile: the *Requirement Load* and the *Dependent
  Reload*. When unloading a modulefile, *Dependent Unload*, *Useless
  Requirement Unload* and *Dependent Reload* actions are triggered.
  (see Automated module handling mode section in MIGRATING document)

* Track the loaded modules that have been automatically loaded (with
  environment variable "MODULES_LMNOTUASKED") to distinguish them from
  modules that have been explicitly asked by user. This information
  helps to determine what module becomes a useless requirement once
  all its dependent modules are unloaded.

* Track in saved collections the loaded modules that have been
  automatically loaded by add of a "--notuasked" argument to "module
  load" collection lines. So this information is restored in loaded
  environment when collection is restored. This "--notuasked" argument
  is ignored outside of a collection restore context.

* Consider modules loaded from a "module source" file as explicitly
  asked by user.

* Install: add "--enable-auto-handling" configure option to enable or
  disable the automatic modulefile handling mechanism.

* Process list of loaded modules or modules to load one by one during
  the "restore", "purge" and "reload" sub-commands whatever the auto
  handling mode is.

* Add the ability to control whether the auto_handling mode should be
  enabled or disabled with an environment variable called
  "MODULES_AUTO_HANDLING" or from the command-line with "--auto" and "
  --no-auto" switches. These command-line switches are ignored when
  called from modulefile.

* Init: add pager-related command-line options in shell completion
  scripts.

* Doc: describe "MODULES_LMCONFLICT", "MODULES_LMPREREQ" and
  "MODULES_LMNOTUASKED" in module.1 man page.

* Add "-f" and "--force" command-line switches to by-pass dependency
  consistency during "load", "unload" or "switch" sub-commands. (see
  By-passing module defined constraints section in MIGRATING document)

* Disallow collection "save" or loaded modules "reload" if some loaded
  modules have some of their dependency constraints unsatisfied.

* The *Dependent Reload* action of a "load", "unload" and "switch"
  sub-commands excludes modules that have unsatisfied constraints and
  includes modules whose constraints are satisfied again (when sub-
  command process solves a conflict for instance).

* Doc: describe "--force", "--auto" and "--no-auto" command-line
  switches and "MODULES_AUTO_HANDLING" variable in module.1 man page.

* Ignore directories ".SYNC" (DesignSync) and ".sos" (SOS) when
  walking through modulepath directory content. (contribution from
  Colin Marquardt)

* Install: look for "make" rather "gmake" on MSYS2.

* Fix "exec()" usage in Python module function definition to retrieve
  the correct return status on Python3.

* Cookbook: add the *top-priority-values* and *unload-firstly-loaded*
  recipes.

* Install: add "gcc" to the build requirements in RPM specfile.

* Silent any prereq violation warning message when processing
  *Dependent Reload* mechanism or "purge" sub-command.

* Doc: mention "createmodule.sh" and "createmodule.py" scripts in FAQ.
  (fix issue#189)

* Register all alternative names of loaded modules in environment with
  "MODULES_LMALTNAME" variable. These names correspond to the symbolic
  versions and aliases resolving to the loaded modules. Helps to
  consistently solve "conflict" or "prereq" constraints set over these
  alternative names. (fix issue#143 / see Consistency of module
  load/unload commands in modulefile section in MIGRATING document)

* Doc: describe "MODULES_LMALTNAME" in module.1 man page.

* Install: add "--with-bin-search-path" configure option to get in
  control of the path list used to search the tools required to build
  and configure Modules. (fix issue#164)

* Install: add "--enable-silent-shell-debug-support" configure option
  to add the ability to control whether or not code to support silent
  shell debug should be added to the module function and sh-kind
  initialization scripts. (fix issue#166)

* Install: add "--enable-quarantine-support" configure option to add
  the ability to control whether or not code to support quarantine
  mechanism should be added to the module function and initialization
  scripts. (fix issue#167)

* Check version set in modulefile magic cookie. If modulefile sets a
  version number greater than "modulecmd.tcl" script version, this
  modulefile is not evaluated like when no magic cookie is set at all.
  (fix issue#171 / see Express Modules compatibility of modulefile
  with versioned magic cookie section in MIGRATING document)

* Fix uninitialized variable in procedure producing list of element
  output. (fix issue#195)

* Ensure the consistency of "module load" modulefile command once the
  modulefile defining it has been loaded by assimilating this command
  to a "prereq" command. Thus the defined constraint is recorded in
  the "MODULES_LMPREREQ" environment variable. Same approach is used
  for "module unload" modulefile command which is assimilated to a
  "conflict" command. Thus the defined constraint is recorded in the
  "MODULES_LMCONFLICT" environment variable. (see Modulefile alias and
  symbolic modulefile name consistency section in MIGRATING document)

* Only look at loaded modules when unloading so unloading an
  nonexistent modulefile does not produce an error anymore. (fix
  issue#199)

* Report error raised from modulefile evaluation as "ERROR" rather
  "WARNING", like when a conflict constraint is hit. Moreover this
  kind of evaluation error is now silenced on global evaluation like
  when processing "avail" or "search" sub-commands.

* Record messages to report them by block on when processing a "load"
  or an "unload" modulefile evaluation to improve readability on these
  evaluating modes that may cascade additional actions. (see Improved
  module message report section in MIGRATING document)

* Foreground "load", "unload", "switch" and "restore" actions (i.e.,
  asked on the command-line) now report a summary of the additional
  load and unload evaluations that were eventually triggered in the
  process.

* Support "del" and "remove" aliases for "unload" sub-command like on
  compatibility version. (fix issue#200 with contribution from
  Wenzler)

* Correctly transmit the arguments along with the command to execute
  on "system" modulefile command. (fix issue#201)

* Contrib: add "mt" utility script which helps to run just specific
  part of the test suite.

* Introduce "set-function" and "unset-function" modulefile commands to
  define shell function on sh-kind and fish shells. (fix issue#193
  with contribution from Ben Bowers)


Modules 4.1.4 (2018-08-20)
==========================

* Doc: fix typo on "getenv" command description in modulefile(4) man
  page and clarify this command should be preferred over "::env"
  variable to query environment variable value in modulefile.

* Init: fix "bash" and "zsh" completion scripts to enable Extended
  Regular Expression (ERE) on "sed" command with "-E" argument (rather
  "-r") for compatibility with OS X's and BSDs' sed. (fix issue#178)

* Handle default version sets on an hidden modulefile (were not found
  previously). (fix issue#177)

* Init: fix "ksh" initialization script for ksh88 compatibility. (fix
  issue#159)

* Install: use "sed" command rather "grep" and "cut" in "configure"
  and "Makefile" scripts. (fix issue#175 with contribution from
  Michael Sternberg)

* Fix typo, tab indentation and pipe opening mode on "createmodule.py"
  utility script. (contribution from Jan Synacek)

* Check "ModulesVersion" value set from ".version" rc file to ensure
  this value refers to a version name in current directory. Report
  error if a nested value is detected and ignore this value. (fix
  issue#176)


Modules 4.1.3 (2018-06-18)
==========================

* Make "setenv" command alter "env" Tcl global array during "help",
  "test" or "whatis" evaluation modes. (fix issue#160)

* Doc: describe MANPATH variable special treatment on compatibility
  version in diff_v3_v4 document.

* Initialize and export _moduleraw SH shell function if "stderr" is
  attached to a terminal. Was previously checking "stdout". (fix
  issue#169)

* For "csh" shells, quote code generated by modulecmd.tcl to pass it
  to the "eval" shell command.

* Escape special characters when producing code to define shell
  aliases (fix issue#165)

* Correct modulefile lookup when a modulefile directory is overwritten
  by a module alias definition but it contains an empty sub-directory.
  (fix issue#170)

* Doc: describe "getenv" command in modulefile(4) man page.

* Improve SH shell detection in profile.sh initialization script to
  use shell variable on "bash" or "zsh" to determine current shell
  name. (fix issue#173)


Modules 4.1.2 (2018-03-31)
==========================

* Add an example global rc file in "contrib/etc" directory that
  ensures "MODULEPATH" is always defined.

* Check "HOME" environment variable is defined on "savelist" and "is-
  saved" commands or raise error if not.

* Fix saving of deep module default version in collection when version
  pinning is disabled: if "foo/bar/version" is default version for
  "foo", collection will retain just "foo" (was retaining "foo/bar").

* Enable to save and restore collections containing full path
  modulefiles eventually with no modulepath defined.

* Run "puts" command not related to "stderr" or "stdout" channels in
  calling modulefile context to correctly get access to the targeted
  file channel. (fix issue#157)

* Quote "autoinit" result for eval interpretation on SH-kind shells to
  avoid parameter expansion to randomly occur on generated code
  depending on file or directory names of current working directory.
  (fix RH bug#1549664)

* Ignore empty elements found in "MODULEPATH", "LOADEDMODULES" or
  "_LMFILES_" to ensure all elements in these variables are non-empty
  strings.

* Raise error if loaded environment is in an inconsistent state when
  calling commands requiring correlation of information from the
  "LOADEDMODULES" and the "_LMFILES_" environment variables. Error
  raised on "load", "unload", "switch", "reload", "purge", "list",
  "save" and "restore" commands.  May affect "info-loaded" or "is-
  loaded" commands if module passed as argument to these command is
  specified as a full path modulefile.

* Fix "list" command to process loaded modules information before
  performing any content output.

* Install: adapt "configure" script and Makefiles to support
  installation on Cygwin system.

* Detect terminal width on Windows "cmd" terminal with "mode" command.

* Improve Windows "cmd" shell support: error code returned, echoing
  text, shell alias creation and removal, working directory change.

* Raise error when an empty module name is passed to module sub-
  commands like "load", "display" or "unload".

* Raise error when an empty collection name is passed to module sub-
  commands like "save", "saveshow" or "restore".

* Raise error when an empty path is passed to module "unuse" sub-
  command, like already done on "use" sub-command.

* Clear argument list if an empty module command name is passed.

* Fix "module" function definition for all shells in "autoinit"
  command to correctly handle empty-string parameters or parameters
  containing white-spaces, quotes, escape characters.

* Fix "module" function definition for Python to accept being called
  with no argument.

* Fix parameter expansion on "module" function for all SH-kind shells
  when quarantine mode is activated.

* Escape "\" character when producing R shell code.


Modules 4.1.1 (2018-02-17)
==========================

* Make separator lines, used on "display" command result for instance,
  fit small screen width.

* Install: give ability to build and install Modules from git
  repository without documentation if "sphinx-build" cannot be found.

* Install: adapt "configure" script and Makefiles to support
  installation on FreeBSD, Solaris and OS X systems. (fix issue#147)

* Rework code generated by "autoinit" for sh-kind shells to avoid use
  of local variables as those are defined differently through the sh
  variants. (also fix issue#147)

* Init: use a default value on undefined variables in sh-kind scripts
  to avoid unbound variables in bash "-eu" mode. (fix issue#151)

* Correctly detect terminal column number on Solaris.

* Init: fix csh init script to get compatibility with pure csh shell

* Sanitize content of "MODULEPATH" before using it at run-time, to
  make potential relative paths absolute, remove trailing slashes,
  etc. (fix issue#152)

* Check loaded modulefiles still exists before displaying statistics
  on them during a "list" action.

* Use a specific reference counter variable name
  ("MODULES_MODSHARE_<VAR>" instead of "<VAR>_modshare") for DYLD-
  specific variables. (fix issue#153)

* No error raise when updating a DYLD or LD path-like variable on OS X
  when System Integrity Protection (SIP) is enabled. In this
  situation, these variables are not exported in subshell context, so
  they appear undefined.

* Init: protect arguments passed to the "_moduleraw" sh function from
  interfering content of current working directory. (fix issue#154)

* Install: move "hostname" RPM requirement to the compat sub-package.

* Start pager process only if some text has to be printed. (partially
  fix issue#146)

* Ignore "PAGER" environment variable to configure Modules pager to
  avoid side effects coming from a general pager configuration not
  compatible with Modules pager handling. (fix issue#146)

* Do not blank anymore default Modules pager options if default pager
  is "less" when the "LESS" environment variable is defined. (fix
  issue#146)

Warning:

  With this bugfix release, changes have been made on the pager setup
  to avoid side effects coming from the system general pager
  configuration. As a result "PAGER" environment variable is now
  ignored and "MODULES_PAGER" should be used instead to adapt Modules
  pager configuration at run-time.


Modules 4.1.0 (2018-01-15)
==========================

* Extend stderr output redirection on sh-kind shells to all terminal-
  attached shell session, not only interactive shell session.

* Extend shell code produced by the "autoinit" command to perform the
  same environment initialization as done in "init" shell scripts
  (default value set for module-specific environment variables, parse
  or source of configuration files).

* Make init shell scripts rely on "autoinit" command to define the
  "module" command and setup its default environment.

* Fix error rendering code for Tcl shell by producing a call to the
  "error" procedure.

* Introduce pager support to handle informational messages, using
  "less" command with "-eFKRX" options by default. Environment
  variable "MODULES_PAGER" or "PAGER" may be used to supersede default
  pager command and options. "--paginate" and "--no-pager" switches
  enable or disable pager from the command line.

* Install: add "--with-pager" and "--with-pager-opts" configure
  options to define default pager command and its relative command-
  line options.

* Introduce quarantine mechanism to protect module execution against
  side effect coming from the current environment definition.
  Variables whose name has been put in "MODULES_RUN_QUARANTINE" will
  be emptied or set to the value hold by "MODULES_RUNENV_<VAR>" in the
  modulecmd.tcl run-time environment. Quarantine variable original
  value is then restored within modulecmd.tcl execution context once
  it has started.

* Install: add "--with-quarantine-vars" configure option to define at
  build time the "MODULES_RUN_QUARANTINE" and "MODULES_RUNENV_<VAR>"
  environment variables set in initialization scripts.

* Add "MODULES_SILENT_SHELL_DEBUG" environment variable to disable on
  sh shell and derivatives any "xtrace" or "verbose" debugging
  property for the duration of either the module command or the module
  shell initialization script. (fix issue#121)

* Change error code produced by modulecmd.tcl for the Tcl, Perl,
  Python, Ruby, CMake and R scripting languages to return a 'false'
  boolean value in case of error rather raising a fatal exception.

* Adapt module function definition for Tcl, Perl, Python, Ruby, CMake
  and R scripting languages to always return a value, result of the
  modulecmd.tcl run. When modulecmd.tcl run does not produce a
  specific status, a 'true' boolean value is returned. On CMake,
  resulting value is returned though a "module_result" global
  variable.

* Spool content sent to the stdout channel with "puts" command during
  a modulefile interpretation, to effectively transmit this content to
  stdout after rendering the environment changes made by this
  modulefile. (fix issue#113)

* Introduce "append-path", "prepend-path", "remove-path" and "is-
  loaded" module sub-commands, based on existing modulefile-specific
  Tcl commands. (fix issue#116)

* Introduce "is-saved", "is-used" and "is-avail" modulefile Tcl
  commands and module sub-commands to test availability of collection,
  modulepath or modulefile.

* Raise error when a call to "path" or "paths" module sub-commands is
  attempted during a modulefile interpretation. Both commands now
  return text rather print text on scripting languages. An empty
  string is returned in no match case instead of a false boolean
  value.

* Introduce "module-info loaded" modulefile command and its module
  sub-command counterpart "info-loaded". This new command returns name
  of the modules currently loaded corresponding to the name passed as
  argument. (fix issue#3)

* Fix "is-loaded" command to correctly handle multiple module names
  passed as argument (fix issue#138)

* Support no argument on "is-loaded", "is-saved" and "is-used"
  commands to return if anything is respectively loaded, saved or
  used.

* Interpret "module source" command set in modulefile in "unload" mode
  when the modulefile itself is interpreted in this mode.

* Consider a modulefile passed with name starting by "./" or "../" a
  full path name modulefile, like those starting by "/". These kind of
  names are converted to absolute path names, for instance to register
  them in loaded modulefile list during a "load" command.

* Correlate modulefile passed as full path name (starting by either
  "./", "../" or "/") to already loaded modulefile registered with
  regular module name (file name without its modulepath prefix) to
  prevent for instance from loading twice same modulefile. Correlate
  in the same way regular module name to already loaded full path name
  modulefile.

* Introduce "MODULES_COLLECTION_PIN_VERSION" environment variable to
  record modulefile version number when saving collections even if
  version corresponds to the default one. (fix issue#89)

* Fix location of "etc/rc" global RC file to "@prefix@/etc/rc" instead
  of "$MODULESHOME/etc/rc" not to depend on "MODULESHOME" environment
  variable value.

* Strengthen argument check for "append-path", "prepend-path" and
  "remove-path" modulefile Tcl commands and module sub-commands. Raise
  error if argument list is not correct.

* Fix support for the "--delim=C" argument form on "append-path",
  "prepend-path" and "remove-path" commands.

* Fix path reference counter handling in case path element is an empty
  string. Distinguish an empty path element from a variable set empty
  to clear it.

* Pass multiple path elements separated by delimiter character as one
  string on "append-path", "prepend-path" and "remove-path" commands.

* Accept multiple path element arguments on "append-path", "prepend-
  path" and "remove-path" commands.

* Introduce the "--duplicates" argument option to "append-path" and
  "prepend-path" commands to add a path element already registered in
  variable.

* Introduce the "--index" argument option to "remove-path" command to
  delete a path entry by passing its position index in variable.

* Provide the ability to setup a site-specific configuration sourced
  at the start of "modulecmd.tcl" main procedure. This configuration
  is a Tcl script named "siteconfig.tcl" which enables to supersede
  any Tcl definition made in "modulecmd.tcl". Location of this file is
  controlled at configure time with the "--etcdir" option.

* Add the ability to handle paths containing reference to environment
  variable in "MODULEPATH". When these kind of paths are used by
  "module" command, the variable references are converted to their
  corresponding value or to an empty string if they are not defined.

* Enclose value set to environment variable on Tcl within curly braces
  rather double quotes to protect special characters in it from
  interpretation.

* Correctly parse ".modulespath" initialization file to handle lines
  without any "#" character or to handle files with no content to
  extract.

* Re-introduce the "--enable-versioning" configure option, which
  appends Modules version to installation prefix and deploy a
  "versions" modulepath shared between all versioning enabled Modules
  installation. A modulefile corresponding to Modules version is added
  to the shared modulepath and enables to switch from one Modules
  version to another.

* Fix removal of CMake generated temporary script file by stripping
  newline character from script file name.

* Add "MODULES_CMD" environment variable to expose path to the
  currently active module command script. This variable is set at
  initialization time.

* Introduce "modulecmd" wrapper script, installed in binary directory,
  which executes the active module command.

* Fix modulefile Tcl interpreter reset when handling list variables.
  (fix issue#145)

* Introduce 'module-virtual' modulefile Tcl command to associate a
  virtual module name to a modulefile. This module can be located with
  its virtual name and the associated modulefile is the script
  interpreted when loading, unloading, etc.

* Resolution of relative paths occurring during a modulefile
  interpretation to target a modulefile or a modulepath now takes the
  directory of the currently interpreted modulefile as the current
  working directory to solve the relative paths.


Modules 4.0.0 (2017-10-16)
==========================

Starting with this release, modules-tcl has become Modules. The
following changes describe the differences with last modules-tcl
release (1.923). To learn about the changes between this release and
last Modules 3.2 release, please see the New features document.

* Relax constraint on command-line argument position so options and
  switches can be passed either before or after command name.

* Report "unsupported option" warning rather stop on error when
  compatibility-version specific command-line switches are passed ( "
  --force", "--human", "--verbose", "--silent", "--create", "--icase",
  "--userlvl").

* Keep empty "module load" line in shell configuration files after
  running the "initrm" or "initclear" commands.

* Always return the value of "tcl_platform(osVersion)" for "uname
  release"

* Optimize code output, for Perl to only return "1;" once for a no-
  operation situation and for Python to not "import os" when there is
  only an error to render.

* Use value of system command "uname -n" for "uname nodename".

* Add support for CMake *shell*

* Ignore "/" character used as suffix in modulefile name passed on
  command line.

* Rename Perl initialization script in "perl.pm" and Python in
  "python.py".

* Add support for Ruby *shell* (with contribution from Tammo Tjarks)

* Add support for R *shell* (with contribution from Roy Storey)

* When a *default* is set for a given module name, target modulefile
  can be referred on as *modulename/default* in addition to just
  *modulename*.

* Locate symbolic versions on "avail" command even these symbols are
  set over a module alias or another symbolic version. In this
  situation the symbol spread along the resolution path until reaching
  a modulefile.

* Define a more standard shebang on modulecmd.tcl script.

* Determine modulefile corresponding to given module name using the
  loaded context only on "unload" situation.

* Enable to unload *mod/dir/subdir/vers* when unload of *mod* or
  *mod/dir* asked. Was previously working only if deep module to
  unload was also the default version for these root names.

* Make -l/-t switches mutually exclusive. Last switch mentioned on the
  command-line is honored.

* Output parsable modulepath header when -l/-t switches are enabled.

* When searching for a module in a given modulepath directory, if a
  module alias or a symbolic version matches searched module but the
  target of this alias or symbol is not found in current modulepath
  directory, search for this target restarting search from the first
  modulepath in list to ensure modulepath priority.

* Solve aliases or symbolic versions looking for all modulepaths on
  "search" and "paths" commands. Was previously solved if their target
  was found in same modulepath directory.

* Add support for hidden *dot* modulefiles. A hidden modulefile does
  not appear in case of wild search, it is only returned when search
  is about its exact name.

* No table header print in --long mode on an "avail" command if no
  result are returned.

* Add blank line between displayed list of elements, for instance
  between modulepath content on "avail" command.

* Improve readability of error messages encountered during modulefile
  execution by putting Tcl error message first after the "Module
  ERROR" prefix.

* Do not exit immediately when an internal error occurs in currently
  interpreted modulefile. Consider this interpretation as failed and
  continue to proceed the other modulefile arguments.

* When multiple modulefiles are passed on "display", "help" and "test"
  commands only output one separator line between 2 interpreted
  modulefiles.

* Fix environment settings stack handling issue when restoring stack
  after a failed attempt to load a modulefile in a modulefile.

* Failed attempt to load or unload a modulefile within a modulefile
  now leads to this upper modulefile load or unload failure.
  Previously upper modulefile were loaded respectively unloaded even
  if its dependent sub-modulefile failed to load or unload.

* During a "switch" command, if the unloading part fails the loading
  part will not be tried. Unloading part fails if module to unload
  does not exist or its unload interpretation raise error.

* Init: use "module source" rather shell command "source" to load
  modulerc system configuration in sh-kind, csh-kind and fish shell
  init scripts.

* Install: transform configuration options to bind to an existing
  compatibility Modules version into option (--enable-compat-version)
  to build and install this compatibility version along with main
  version.

* Init: adapt initialization scripts to handle both main and
  compatibility version. By default a shell script enables main
  version and if the environment variable MODULES_USE_COMPAT_VERSION
  is set to 1, the compatibility version is enabled instead of main
  version.

* Install: import from compatibility version and install "add.modules"
  and "mkroot" utility scripts (scripts developed by R.K. Owen).

* Install: update RPM spec file to handle compatibility version as a
  "compat" sub-package.

* Add completion script for Fish shell (contribution from BEFH).

* Doc: extend content of diff_v3_v4 to details all noticeable changes
  between v3.2 and v4.0.

* Doc: introduce MIGRATING guide to learn the major changes when
  moving from v3.2 to v4.0.

* Fix "list" command when full pathname modulefile is loaded (fix
  bug#132)

* Install: handle version number though git tags in scripts,
  documentation and RPM spec file.

* Doc: migrate documents from POD format to reStructuredText to
  benefit from Sphinx documentation framework and Read The Docs
  publishing capabilities.

Above changes describe the differences with modules-tcl release 1.923.
To learn about the changes between Modules 4.0 and last Modules 3.2
release, please see the New features document.


modules-tcl-1.923 (2017-07-20)
==============================

* Fix "aliases" command when a global or user RC file is set.

* Find and solve global or user RC aliases and symbolic versions on
  "search", "whatis" and "paths" commands.

* Do not look at currently loaded modules to resolve the target of a
  module alias.

* Rework default and latest versions search on "avail" command.
  Correct display when at a given level a sub-directory element is
  last element in directory among modulefiles. Previously sub-
  directory was printed but last file among modulefiles was also
  printed (2 latest versions at the same level). A directory tagged
  "default" does not appear anymore in default listing result as its
  content (the default version found in that directory) will be
  displayed.

* When an alias is set and overrides name of an existing directory,
  take this alias into account for default and latest choice and
  ignore directory content.

* Bad default set will lead to no result displayed for the
  corresponding module in case of default "avail" display.

* Correct inclusion of aliases in output result when these aliases are
  not part of the exact same module path than module path of the
  search.

* Rewrite existing shell initialization file with initadd,
  initprepend, initswitch, initrm and initclear commands rather than
  writing a new file then copying this new file to replace the
  existing initialization file. In addition only re-writes shell
  initialization file if its content need to be altered.

* Raise an error on initadd, initprepend, initswitch, initrm and
  initclear commands when no "module load" line are found in shell
  initialization file.

* Normalize error messages for the various collection-related commands
  when collection cannot be accessed.

* Cleanup existing reference counters of a path list variable when
  this variable is altered by a "setenv" or an "unsetenv" command.

* Init: do not pollute tab-completion with moduleraw command. (Bert
  Wesarg)

* Make use of the same Tcl interp for each modulefile interpretation
  and use another one for each modulerc (but the same for each
  modulerc). By doing so we proceed like on C-version where same
  interpreter is used across modulefile or modulerc interpretation.
  Huge performance improvement is achieved with this change on
  commands making intensive use of interp like "avail". Interpreter
  state is reset from one interpretation to another: the initial
  variable and procedure state is restored before each new
  interpretation to avoid spread of definitions from one
  interpretation to another. Also in case of nested interpretation
  each interpretation level has its own interpreter so a module loaded
  by another does not influence the interpretation of the module
  loading it.

* Improve performance of aliases and symbolic versions resolution by
  computing these resolution at definition time. As a consequence
  resolution loop are not registered anymore and produce an error
  message when spotted not at display time.

* Reduce number of "access" system call by trying access to modulefile
  when reading the content of a modulefile directory rather testing
  access before trying it.

* No error raise on empty argument list for load. To cope with initadd
  behavior that requires at least an empty "module load" line in
  startup files. (fix SF bug#88)

* Fix initadd to handle load line without trailing space. Was
  previously expecting load directive to be written "module load "  to
  get a match. With fix, "module load" line will also be matched.

* Like C-version catch raised error when break or continue are called
  from outside of a loop to handle them as when they are called from
  modulefile main body. (fix SF bug#87)

* Return error on "module use" command when an empty path string is
  provided rather ignoring it.

* Workaround "min" and "max" functions and "lreverse" procedure for
  correct operations under Tcl version 8.4.

* Install: add --with-tclsh configure option to give the ability to
  choose the Tcl interpreter shell to setup in initialization scripts.

* Handle error raised from the ModulesDisplay, ModulesHelp and
  ModulesTest procedures in the same way than for the evaluation of
  the modulefile content. An error occurring during the evaluation of
  the modulefile content will lead to no evaluation of the "display",
  "help" and "test" command specific functions.

* Remove "debug" module command

* Doc: describe "path", "paths" and "autoinit" module command.

* Correct use of xrdb tool when not installed in default path.

* Fix "init*" module commands to behave more like C-version and
  document remaining differences in diff_with_c-version.

* Init: make "sh" init script closer to POSIX specification to support
  sh flavors different than Bash or Zsh like Dash.

* Fix column-mode display for very short width terminal.

* Install: introduce an "install" non-regression testsuite which is
  triggered by the "make testinstall" command and checks modules-tcl
  installation is operational.

* Init: fix modulerc load test on "fish" init script.

* Init: fix interactive shell test on "sh" init script.

* Install: add --enable-example-modulefiles configure option that
  install by default some modulefiles provided as example in the
  system modulefiles directory.

* Install: when uninstalling, do not remove modulefiles directory if
  it is not empty.

* Add completion script for Zsh shell.

* Add "module test" command to trigger when called execution of a
  ModulesTest procedure in target modulefile following same kind of
  mechanism than "module help".


modules-tcl-1.832 (2017-04-29)
==============================

* Fix "getenv" sub-command to correctly return environment variable
  value.

* Clarify in man-pages display of module alias and symbolic version-
  name on "avail" command and management of file access issue when
  locating modulefiles.

* Distinguish access issue (permission denied) from find issue (cannot
  locate) when trying to access directly a directory or a modulefile
  as done on "load", "display" or "whatis" commands. In addition on
  this kind of access, not readable .modulerc files are ignored rather
  producing a missing magic cookie error.

* When mode is set to unload, "module load" commands in modulefile are
  interpreted as "module unload" commands. To guaranty correct
  behavior regarding requirements, the module list passed to the load
  command is reversed to unload the modulefiles in the reverse order
  than they have been loaded.

* Correct "display" command to only report module commands set in
  modulefile and not those set in the various .modulerc on the path
  toward this modulefile.

* Fix bash and tcsh completion scripts to eliminate symbolic version
  names from "avail" command result.

* Improve "avail" command when a symbolic version-name is passed as
  argument to return the modulefile target of this symbolic version-
  name.

* When looking for an implicit default in a directory, now a module
  alias is taken into account so it can be returned as the last
  element in it (highest numerically sorted version).

* Fix "list" command to correctly display the "default" tag along
  loaded modules when set via a .version file.

* Fix long output of "list" command to display the symbolic version-
  names associated to each loaded module if any.

* Improve "avail" command to return alias module when an alias name is
  passed as argument.

* On a "--default" listing, a modulefile does not appear anymore if a
  directory is set default at the same level. On a "--latest" listing,
  a directory does not appear anymore if set default but not the
  latest.

* Read modulerc and validate its header in a single open/read/close
  sequence instead of two in order to reduce to number of IO
  operations during an "avail" command.

* Drastically reduce grid size computation time which removes overhead
  when displaying module avail results in column-mode.

* Translate module name to currently interpreted module name when name
  correspond to the last part this interpreted module only in case of
  symbolic version-name or alias resolution.

* Avoid resetting regular path (/usr/bin) or manpath (/usr/share/man)
  when switching from Tcl to C version in switchml utility.

* Raise error on x-resource if DISPLAY environment variable is not
  set.

* Fix lisp init script which was broken for environment change
  actions.


modules-tcl-1.775 (2017-03-07)
==============================

* Improve README with examples, requirements, links, etc. Also update
  INSTALL documentation with details on the new configure/make/make
  install process.

* Add display of a release date next to the version number when
  calling for "--help" or "--version".

* Update diff_with_c-version document to describe the features of the
  Tcl-version that are not supported on the C-version. Also state that
  the diff takes C version 3.2.10 against Tcl version 1.729 as a
  basis.

* Introduce "switchml" tool, a shell function (or alias for csh or
  tcsh shells) that swap currently enabled Modules version (C or Tcl)
  by the other version (C or Tcl). Configure option "--with-cver-
  initdir" must be defined to enable "switchml" in initialization
  script.

* Define a PATH and MANPATH in shell initialization scripts that point
  to the defined modules-tcl installation directories.

* Give ability to generate distribution tarball from the git
  repository with Makefile "dist" target.

* Introduce an installation process for this software following the
  configure/make/make install fashion. Configure step enables to
  choose installation paths and init scripts features to activate.
  Make step mainly translates init scripts with the configuration set.
  Make install creates target directories and copy files into them.

* Fix MODULESHOME setup in autoinit command to define it as an
  absolute path and set it to the upper directory when modulecmd.tcl
  is located in a "bin" or a "libexec" directory.

* Correct alias and version resolution on avail command which was
  erroneous in case of a modulefile holding symbols (like "default")
  and targeted by aliases. Avail output was showing the aliases
  holding the symbols instead of the modulefile.


modules-tcl-1.729 (2017-02-01)
==============================

* Add documentation in module(1) man page on the modulefile collection
  concept and the relative "save", "restore", "saverm", "saveshow" and
  "savelist" commands.

* Add document to list the differences of the functionalities that can
  be found on the C-version of the Modules package compared to the
  Tcl-version.

* Improve modulecmd.tcl shebang to only search "tclsh" once if found
  in PATH.

* Add "module-info mode" check against "remove" and "switch" values.

* Introduce "module-info command" Modules-specific Tcl command to
  distinguish complex "load" or "unload" commands that cannot be
  determined with "module-info mode" alone. For instance a modulefile
  can now be aware that a "switch", a "restore" or a "purge" command
  is currently being run.

* Enable usage of "module-info" Modules-specific Tcl command from a
  modulerc file.

* Fix "module-info specified" Modules-specific Tcl command.

* No exit raise on modulefile or modulerc error during "avail",
  "aliases", "whatis" and "search" commands to avoid harming results
  from these global commands if error exists in a few modulefiles.

* Exit with error code when a critical error is encountered when
  interpreting a modulefile or a modulerc.

* Inhibit non-critical error report raised from modulefiles during
  "avail", "aliases", "whatis" and "search" commands to avoid error
  flood when parsing all modulefiles or modulercs.

* Handle multiple lines of "module-whatis" Modules-specific Tcl
  commands defined for the same modulefile.

* Handle multiple arguments passed to the "module-whatis" Modules-
  specific Tcl commands. They are joined to get a single line of text.

* Return error on "whatis" command if searched modulefile is not
  found.


modules-tcl-1.704 (2017-01-20)
==============================

* Set path variable counter to 1 for paths without a known reference
  count (was previously set to 999999999).

* Introduce "envml" utility which acts as an application launcher
  where module commands are instantiated to setup environment before
  launching the given application.

* Always register paths provided to be part of MODULEPATH environment
  variable as absolute paths to get independent from the current
  working directory.

* Inhibit next modulefiles interpretation with "exit" Modules-specific
  Tcl command only if current mode is "load".

* Add argument to "module-info shell" and "module-info shelltype" to
  test current shell or shelltype value.

* Fix use of "default" version-name to not consider it as a module
  symbol if a modulefile is named "default".

* Fix path variable counters when ":" character is used in elements of
  a path-like variable.

* Update module(1) and modulefile(4) man pages to clear content
  specific to the C version of Modules and add content specific to or
  adapt content that behave differently on this Tcl version.

* Fix TCLSH variable issue in Python init script.


modules-tcl-1.677 (2017-01-04)
==============================

* Make "switch" command handle a single argument. The modulefile to
  switch to is the one passed on the command-line and the modulefile
  to unload is assumed to be the currently loaded module with the same
  root name as this modulefile specified on the command-line.

* Make "switch" command idempotent by always ending up with "old"
  unloaded and "new" loaded, whatever the starting situation is.

* Fix "exit" Modules-specific Tcl command.

* Add "refresh" command as alias on "reload" command.

* Add dummy "module-log", "module-trace", "module-user" and "module-
  verbosity" Modules-specific Tcl commands to enable support for
  modulefiles using them.

* Fix "system" Modules-specific Tcl command  to behave like described
  on the man page.

* Fix "module list" when module loaded with full path

* Disable "g_force" property by default to avoid loading a modulefile
  already loaded. It also avoids path element reference counting to
  get increased when the same module is asked twice for load.

* Clarify module-info "mode" option and set "help" mode on "module
  help" command.

* Clarify module-info "flags" and "user" options.

* Handle empty or separator path on "add-path" ad "unload-path"
  commands.

* Delete environment variable targeted by an "unsetenv" command on
  "unload" mode if no value has been provided along. On display mode,
  print environment variable value if any has been passed to
  "unsetenv" command.

* When setting Tcl variable, enclose value within double quotes.

* Fix perl quoting style for variable set, escape single quotes rather
  double quotes.

* Call "unuse" command instead of "use" command on a "module unload".

* Fix "continue" Modules-specific Tcl command.

* Add "chdir" Modules-specific Tcl command.

* Fix "break" Modules-specific Tcl command.


modules-tcl-1.655 (2016-11-23)
==============================

* No display of modulepath header if no module found in it.

* Remove call to "module aliases" on "module avail" command, as
  aliases are now directly included in the "avail" results.

* Include module aliases in the displayed result of an "avail"
  command. Also display aliases defined in a global or user modulerc
  file.

* Exit with error code if error occurred on display or help commands.

* Fix module-info symbols resolution.

* Better handling of .modulerc and .version files when searching for a
  modulefile.

* Fix module-info version resolution.

* Fix module-info alias resolution.

* Register alias and version by the short module name and improve
  their resolution to avoid loop.

* Source $MODULERCFILE/modulerc when $MODULERCFILE is dir.

* Make it so you can do "module avail un", wildcard "*" character
  implied.


modules-tcl-1.632 (2016-09-06)
==============================

* Raise error if command does not receive the excepted number of
  arguments.

* Improve column-mode display to get a denser output on "avail"
  command.

* Standardize the output of Warning, Error, InternalBug and
  ErrorAndExit messages.

* Add short option -d for --delim on prepend-path.

* Introduce collection target concept to distinguish between machines,
  environments or domains that are incompatible with each other.

* Introduce "saveshow" command, to display content of saved
  collections.

* Improve "save" and "restore" commands to handle collection specified
  as absolute or relative file path.

* Introduce "saverm" command, to delete saved collections.

* Enable to "restore" collection with multiple modulefiles specified
  on the same line.

* Fix "restore" command when there is no module to load in collection.

* Fix "restore" command when collection fully rewind module paths.

* Fix "restore" command to preserve module path order set in
  collection.

* Raise error if try to save an empty environment in a collection.


modules-tcl-1.602 (2016-08-13)
==============================

* Add support for Fish shell.

* Import recent tests added to C-version on 10-use and 50-cmds
  testsuites.

* Add short option -d for --delim on append-path and remove-path.

* Fix load and implement unload x-resource.

* Fix Python code that was broken or not Python3-compliant. Fixed code
  is used to define the module command, to render error and to process
  x-resource.

* Always dictionary-sort (also called numerical-sort) list of
  modulefiles or list of collections.

* Fix bash completion script to be compliant with bash posix mode.


modules-tcl-1.578 (2014-12-24)
==============================

* First release to be described in this NEWS file but it does not mean
  this is the first version of modules-tcl as this Modules flavor is
  born in 2002.

* At this stage, modules-tcl handles a majority of the module commands
  and modulefile Tcl commands available on C version.
