[CMake] No-op command?

[Philip Semanchuk]

Hi there,
Does CMake have a no-op command, like 'pass' in Python or ';' in C? I 
sometimes want to create a construct like this:

IF(CMAKE_SYSTEM_NAME STREQUAL "Windows")
     # Under Windows we do nothing because blah blah blah
     ...no-op...
ELSE()
     ...do something...
ENDIF(CMAKE_SYSTEM_NAME STREQUAL "Windows")


Thanks
Philip