[CMake] Test if ENV${VAR} is set

[David Cole]

On Fri, Sep 14, 2012 at 4:17 PM, Bogdan Cristea <cristeab at gmail.com> wrote:
> On Friday 14 September 2012 16:13:16 Davis Ford wrote:
>> if("$ENV{FOO_HOME}" MATCHES "")
>>    message("You must set FOO_HOME")
>>    return()
>> endif()
>
> Try something like this
>
> if(NOT ENV{FOO_HOME})
> message("etc")
> endif()
>
> --
> Bogdan
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I would use the double quotes like you had originally, but use
STREQUAL instead of MATCHES. Or use MATCHES "^$" to match ONLY the
explicitly empty string, because MATCHES "" basically matches
everything because everything "contains" the empty string...

HTH,
David