CMakeDependentOption

Macro to provide an option dependent on other options.

This macro presents an option to the user only if a set of other conditions are true.

cmake_dependent_option
cmake_dependent_option(<option> "<help_text>" <value> <depends> <force>)

Makes <option> available to the user if the semicolon-separated list of conditions in <depends> are all true. Otherwise, a local variable named <option> is set to <force>.

When <option> is available, the given <help_text> and initial <value> are used. Otherwise, any value set by the user is preserved for when <depends> is satisfied in the future.

Note that the <option> variable only has a value which satisfies the <depends> condition within the scope of the caller because it is a local variable.

Example invocation:

cmake_dependent_option(USE_FOO "Use Foo" ON "USE_BAR;NOT USE_ZOT" OFF)

If USE_BAR is true and USE_ZOT is false, this provides an option called USE_FOO that defaults to ON. Otherwise, it sets USE_FOO to OFF and hides the option from the user. If the status of USE_BAR or USE_ZOT ever changes, any value for the USE_FOO option is saved so that when the option is re-enabled it retains its old value.

Added in version 3.22: Full Condition Syntax is now supported. See policy CMP0127.