.. _stdlib_module_group:

=========================================
Calls into every member of a module group
=========================================

.. das:module:: module_group

The MODULE_GROUP module calls into every member of a module group.
``call_module_group("group", "entry", args...)`` expands at compile time to one
``member::entry(args...)`` call per module registered under the group, sorted by
member path, so the module that wrote ``require [group]`` reaches its members
without naming them. A member without the entry is a compile error naming the
call; a group nothing joined expands to nothing.

All functions and symbols are in "module_group" module, use require to get access to it.

.. code-block:: das

    require daslib/module_group



+++++++++++
Call macros
+++++++++++

.. _call-macro-module_group-call_module_group:

.. das:attribute:: call_module_group

`call_module_group("group", "entry", args...)` expands to one `member::entry(args...)`
call per member, sorted by member path, an empty group to nothing; an argument that is
not a constant or a plain variable is bound to a local ahead of the calls, so it is evaluated once.



+++++++++++++
Group members
+++++++++++++

  *  :ref:`module_group_module_name (member: string) : string <function-module_group_module_group_module_name_string>`

.. _function-module_group_module_group_module_name_string:

.. das:function:: module_group_module_name(member: string) : string

The module a group member's require path names: its last segment, less the `.das` a
relative spelling (`./foo.das`) may carry.


:Arguments: * **member** : string