Andres Freund <and...@anarazel.de> writes: > On 2018-09-21 18:00:35 -0400, Tom Lane wrote: >> If you want to rename it, then to what? VA_ARGS_NARGS, perhaps?
> I like your suggestion. I mainly didn't like the PP_ prefix. Sold. The original author overcomplicated it anyway; I now have /* * VA_ARGS_NARGS * Returns the number of macro arguments it is passed. * * An empty argument still counts as an argument, so effectively, this is * "one more than the number of commas in the argument list". * * This works for up to 63 arguments. Internally, VA_ARGS_NARGS_() is passed * 64+N arguments, and the C99 standard only requires macros to allow up to * 127 arguments, so we can't portably go higher. The implementation is * pretty trivial: VA_ARGS_NARGS_() returns its 64th argument, and we set up * the call so that that is the appropriate one of the list of constants. */ #define VA_ARGS_NARGS(...) \ VA_ARGS_NARGS_(__VA_ARGS__, \ 63,62,61,60, \ 59,58,57,56,55,54,53,52,51,50, \ 49,48,47,46,45,44,43,42,41,40, \ 39,38,37,36,35,34,33,32,31,30, \ 29,28,27,26,25,24,23,22,21,20, \ 19,18,17,16,15,14,13,12,11,10, \ 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) #define VA_ARGS_NARGS_( \ _01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \ _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \ _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \ _31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \ _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \ _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \ _61,_62,_63, N, ...) \ (N) from which it's pretty obvious that this really is a simple macro call. I'd first thought it involved macro recursion, but it doesn't. > You earlier were talking about tackling this - do you still want to? I > can otherwise, but it'll not be today, but likely tomorrow. On it now. regards, tom lane