Default and latest version specifiers

Configuration

• Rely on advanced_version_spec option

  • No need for an extra configuration option

  • When option is on it automatically enables use of these two new version specifiers

  • When advanced_version_spec is off, mod@latest is considered as a modulefile name to find

  • in case implicit_default is disabled

    • means a default symbol or a latest symbol should be found defined to respectively make use of the @default or @latest specifiers

    • a not found error is otherwise raised, as specified version does not exist

Specification

• When a default or a latest symbol is defined

  • @default or respectively @latest will resolve to the symbol target

• When no default or latest symbol is defined

  • @default and @latest point to the highest existing version (also called the implicit default)

  • note that if a default symbol is defined but not a latest symbol, @default points to the defined default and @latest points to the highest version that exists

• default or latest version specifiers can be employed:

  • in single version specification: @default or @latest

  • in version list: @vers1,default or @latest,default,vers2

• default or latest version specifiers cannot be employed in version range

  • otherwise an error is raised

• default or latest version specifiers can also be specified with the traditional mod/version syntax

  • for instance mod/default or mod/latest

• When a default or latest modulefile exists

  • @default or respectively @latest will resolve to the existing modulefile

  • no automatic symbol will be recorded in this case as default or latest are regular versions

• To be included in module search result, the version specifiers should fully match search query or search query should not target a specific module version

  • the automatically defined symbolic versions are included in results for queries like mod@latest or mod

  • but not for queries like mod@la, mod@def, mod@lat*, mod@def??lt

• Automatically defined default and latest version specifiers are not displayed to avoid overloading output:

  • on module list output

  • on module avail output

  • on module spider output

  • those three sub-commands only display symbolic versions manually defined

• Alternative module names deduced from the automatically defined version specifiers need to be tracked

  • in loaded environment for each targeted module loaded

  • to keep track loaded module is default or latest version

  • thus keeping ability to answer queries like is-loaded mod@latest from further modulefile evaluation or module command-line

  • this information is kept in the __MODULES_LMALTNAME environment variable, along other alternative names

  • Auto symbols in this variable are recorded with a as| prefix to distinguish them from other alternative names

    • for instance mod/1.2&mod/regular_symbol&as|mod/latest

    • it helps to filter auto symbols from regular symbols that need to be displayed