22 Nov
2012
22 Nov
'12
1:30 p.m.
On 11/22/2012 3:05 AM, Zhenghui Zhou wrote:
On 11/20/2012 7:36 PM, Edward Diener wrote:
On 11/20/2012 7:43 AM, Zhenghui Zhou wrote:
As I known, the undocument interface BOOST_PP_IS_EMPTY is not a general implementation to condider emptiness. There is a undefined behaviours when token concatenation return a invalid preprocessing token. Particularly, gcc restriction reports error.
See BOOST_IS_EMPTY in my variadic macros library in the sandbox.
See also, CHAOS_PP_IS_EMPTY_NON_FUNCTION in Chaos. http://sourceforge.net/projects/chaos-pp/ It is the closest that you can get to a general-purpose emptiness-detection macro. It's only limitation is that the input cannot end in the name of a function-like macro. Regards, Paul Mensonides