| function | |
| -------- | |
| Start recording a function for later invocation as a command:: | |
| function(<name> [arg1 [arg2 [arg3 ...]]]) | |
| COMMAND1(ARGS ...) | |
| COMMAND2(ARGS ...) | |
| ... | |
| endfunction(<name>) | |
| Define a function named ``<name>`` that takes arguments named ``arg1``, | |
| ``arg2``, ``arg3``, (...). | |
| Commands listed after function, but before the matching | |
| :command:`endfunction()`, are not invoked until the function is invoked. | |
| When it is invoked, the commands recorded in the function 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. | |
| Additionally ``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. | |
| 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. |