On Sun, Oct 14, 2018 at 04:29:06PM +0200, René Scharfe wrote: > Anyway, drove the generative approach a bit further, and came up with > the new DEFINE_SORT below. I'm unsure about the name; perhaps it should > be called DEFINE_SORT_BY_COMPARE_FUNCTION_BODY, but that's a bit long. > It handles casts and const attributes behind the scenes and avoids > repetition, but looks a bit weird, as it is placed where a function > signature would go. > > Apart from that the macro is simple and doesn't use any tricks or > added checks. It just sets up boilerplate functions to offer type-safe > sorting. > > diffcore-rename.c and refs/packed-backend.c receive special treatment in > the patch because their compare functions are used outside of sorting as > well. I made them take typed pointers nevertheless and used them from > DEFINE_SORT; the wrapper generated by that macro is supposed to be > private. Given that such reuse is rare and I think we don't need a way > to make it public. > > What do y'all think about this direction? I think it's the best we're likely to do, and is an improvement on the status quo. The patch looks overall sane to me. I think DEFINE_SORT() is a fine name. I think given a macro parameter "foo" you could generate sort_by_foo() and compare_foo(), which would eliminate the extra layer in those two cases you mentioned. But I'm also fine with the approach you've shown here. -Peff
