From 6c3311d53beed5bd229efeaaa4fefc330de3ddea Mon Sep 17 00:00:00 2001 From: "FeRD (Frank Dana)" Date: Sat, 6 Jan 2024 04:19:45 -0500 Subject: Help: Document property redefinition semantics Add a section to the `define_property()` documentation which details the behavior when attempting to redefine an existing property. (The command is silently ignored.) Provide an example using `get_property()` to examine a property definition created with `define_property()`. --- Help/command/define_property.rst | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/Help/command/define_property.rst b/Help/command/define_property.rst index 5278e30..06f2823 100644 --- a/Help/command/define_property.rst +++ b/Help/command/define_property.rst @@ -74,6 +74,42 @@ project via corresponding options to the :command:`get_property` command. underscore. It is recommended that the property name have a prefix specific to the project. +Property Redefinition +^^^^^^^^^^^^^^^^^^^^^ + +Once a property is defined for a particular type of scope, it cannot be +redefined. Attempts to redefine an existing property by calling +:command:`define_property` with the same scope type and property name +will be silently ignored. Defining the same property name for two different +kinds of scope is valid. + +:command:`get_property` can be used to determine whether a property is +already defined for a particular kind of scope, and if so, to examine its +definition. For example: + +.. code-block:: cmake + + # Initial definition + define_property(TARGET PROPERTY MY_NEW_PROP + BRIEF_DOCS "My new custom property" + ) + + # Later examination + get_property(my_new_prop_exists + TARGET NONE + PROPERTY MY_NEW_PROP + DEFINED + ) + + if(my_new_prop_exists) + get_property(my_new_prop_docs + TARGET NONE + PROPERTY MY_NEW_PROP + BRIEF_DOCS + ) + # ${my_new_prop_docs} is now set to "My new custom property" + endif() + See Also ^^^^^^^^ -- cgit v0.12