[CMake] Checking for empty list

[Daniel Dekkers]

Thanks, so...

IF( MYLIST )
	MESSAGE( STATUS "List is not empty" )
ENDIF()

Without the ${...} surrounding MYLIST, which confuses me, but probably makes
sense if you (better than I do) know what you're doing ;-)

-----Oorspronkelijk bericht-----
Van: cmake-bounces at cmake.org [mailto:cmake-bounces at cmake.org] Namens Michael
Wild
Verzonden: vrijdag 25 november 2011 15:15
Aan: cmake at cmake.org
Onderwerp: Re: [CMake] Checking for empty list

On 11/25/2011 02:52 PM, Daniel Dekkers wrote:
> Hi,
> 
>  
> 
> I know it should be out there somewhere in the documentation, but 
> can't find it.
> 
> How do I check for an empty list?
> 
> I can use LIST(LENGTH MYLIST LISTCOUNT) with an extra variable 
> LISTCOUNT but isn't there a single command?
> 
>  
> 
> Thanks,
> 
> Daniel
> 


An empty list is an empty variable, and evaluates to FALSE. So you can use

if(NOT MYLIST)
  message("Either MYLIST is empty or otherwise FALSE")
endif()

Michael
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