Hi, too funny I recently implemented named parameters for macros, too. But differently and specialised (no general-purpose framework or anything - not because it were not doable, but because I didn't need it). Nevertheless, they are used like this MACRO((foo, 77) (bar, int)) which will expand to say MACRO2(int, 77) The idea is "simple": 1. Generate a valid PP-Sequence from this "tuple-sequence"-thing 2. Generate a set of "modifications" by looking up the value of PARAM_ ## param (x), which will expand to (index, x) or something like this. 3. Apply those changes to an initial tuple. 4. Use the tuple to invoke another macro. I do not know which approach should be considered superior. But I really consider both interesting. I used my approach in a usable C++ library already, so the concept (which is the same for both) _is_ practical. Kind regards, Aristid PS: I do not think preprocessor metaprogramming should be over-used but there are a few places where it fits nicely. PPS: Quirks! Am Dienstag, den 24.10.2006, 22:24 +0200 schrieb Tobias Schwinger:
// ---- client code
MY_MACRO( MY_FIRST_ARG(yaba) MY_THIRD_ARG(doo) MY_SECOND_ARG(daba) ) // expands to: yaba daba doo
MY_MACRO( MY_SECOND_ARG(bubu) ) // expands to: 1st_default bubu 3rd_default.
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