mirror of
https://github.com/Kitware/CMake.git
synced 2025-12-31 10:50:16 -06:00
c2efb3efcd
Revise docs for all "Scripting Commands", except four find_XXX that use a macro suite of their own. * Take full advantage of the improved syntax highlighting. * Make consequential use of <..> placeholders. * Clarify things here and there in the text. Specific improvements to some command docs: * "math": Correct description of novel hexadecimal capability. * "if", "foreach", "while": Provide link to "endif" etc * "foreach", "while": Mention "break" and "continue". * "foreach": Simplify explanation of ``RANGE`` and ``IN`` signatures; advise against negative arguments or reverse ranges (compare issue #18461) * "endif", "endfunction" etc: Explain that the argument is optional and maintained for compatibility only
43 lines
1.6 KiB
ReStructuredText
43 lines
1.6 KiB
ReStructuredText
function
|
|
--------
|
|
|
|
Start recording a function for later invocation as a command.
|
|
|
|
.. code-block:: cmake
|
|
|
|
function(<name> [<arg1> ...])
|
|
<commands>
|
|
endfunction()
|
|
|
|
Defines a function named ``<name>`` that takes arguments
|
|
named ``<arg1>``, ...
|
|
The ``<commands>`` in the function definition are recorded;
|
|
they are not invoked until the function is invoked. When
|
|
the function is invoked, the recorded ``<commands>`` are first
|
|
modified by replacing formal parameters (``${arg1}``, ...)
|
|
with the arguments passed, and then invoked as normal commands.
|
|
|
|
In addition to referencing the formal parameters you can reference the
|
|
``ARGC`` variable which will be set to the number of arguments passed
|
|
into the function as well as ``ARGV0``, ``ARGV1``, ``ARGV2``, ... which
|
|
will have the actual values of the arguments passed in.
|
|
This facilitates creating functions with optional arguments.
|
|
|
|
Furthermore, ``ARGV`` holds the list of all arguments given to the
|
|
function and ``ARGN`` holds the list of arguments past the last expected
|
|
argument.
|
|
Referencing to ``ARGV#`` arguments beyond ``ARGC`` have undefined
|
|
behavior. Checking that ``ARGC`` is greater than ``#`` is the only way
|
|
to ensure that ``ARGV#`` was passed to the function as an extra
|
|
argument.
|
|
|
|
Per legacy, the :command:`endfunction` command admits an optional
|
|
``<name>`` argument. If used, it must be a verbatim repeat of the
|
|
argument of the opening ``function`` command.
|
|
|
|
A function opens a new scope: see :command:`set(var PARENT_SCOPE)` for
|
|
details.
|
|
|
|
See the :command:`cmake_policy()` command documentation for the behavior
|
|
of policies inside functions.
|