mirror of
https://github.com/Kitware/CMake.git
synced 2026-06-26 17:58:50 +00:00
92 lines
2.3 KiB
ReStructuredText
92 lines
2.3 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 executed until the function is invoked.
|
|
|
|
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.
|
|
|
|
See the :command:`macro()` command documentation for differences
|
|
between CMake functions and macros.
|
|
|
|
Invocation
|
|
^^^^^^^^^^
|
|
|
|
The function invocation is case-insensitive. A function defined as
|
|
|
|
.. code-block:: cmake
|
|
|
|
function(foo)
|
|
<commands>
|
|
endfunction()
|
|
|
|
can be invoked through any of
|
|
|
|
.. code-block:: cmake
|
|
|
|
foo()
|
|
Foo()
|
|
FOO()
|
|
cmake_language(CALL foo)
|
|
|
|
and so on. However, it is strongly recommended to stay with the
|
|
case chosen in the function definition. Typically functions use
|
|
all-lowercase names.
|
|
|
|
.. versionadded:: 3.18
|
|
The :command:`cmake_language(CALL ...)` command can also be used to
|
|
invoke the function.
|
|
|
|
Arguments
|
|
^^^^^^^^^
|
|
|
|
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. The following
|
|
variables are set in the scope of the function:
|
|
|
|
``ARGC``
|
|
The number of arguments passed into the function.
|
|
|
|
``ARGV``
|
|
The list of all arguments given to the function.
|
|
|
|
``ARGV#``
|
|
The variables ``ARGV0``, ``ARGV1``, ``ARGV2``, ... which will have the
|
|
actual values of the arguments passed in. References 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.
|
|
|
|
``ARGN``
|
|
The list of arguments past the last expected argument.
|
|
|
|
``ARGNC``
|
|
.. versionadded:: 4.5
|
|
|
|
The number of arguments past the last expected argument.
|
|
|
|
See Also
|
|
^^^^^^^^
|
|
|
|
* :command:`cmake_parse_arguments`
|
|
* :command:`endfunction`
|
|
* :command:`return`
|