This is for specifying INCLUDE_DIRECTORIES relevant to the build-location
or the install location for example:
set_property(TARGET foo PROPERTY
INTERFACE_INCLUDE_DIRECTORIES
"$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR};${CMAKE_CURRENT_SOURCE_DIR}>"
"$<INSTALL_INTERFACE:${CMAKE_INSTALL_PREFIX}/include>"
)
A 'bar' target can then use:
set_property(TARGET bar PROPERTY
INCLUDE_DIRECTORIES
"$<TARGET_PROPERTY:foo,INTERFACE_INCLUDE_DIRECTORIES>"
)
and it will work whether foo is in the same project, or an imported target
from an installation location, or an imported target from a build location
generated by the export() command.
Because the generator expressions are only evaluated at build-time, these
new expressions are equivalent to the ZeroNode and OneNode.
The GeneratorExpression test is split into parts. Some shells can't run
the custom command as it is getting too long.