I started out trying to write something like the OP, but changed direction when I convinced myself there would have been no sane way to implement member call syntax. I honestly can't decide if it's cursed or genuinely useful (minus the unicode name, that's cursed).
As if C++ didn't have enough of “black magic” already, there's another layer of that. Just in case you find error messages involving template applications still too readable.
Little reminder that there once was a "C++ error message competition" [0] where your score was measured as "the size of the error message divided by the size of the source code". The winning entry had a score of 5.9 billion.
It's a common extension but it's not standard. Both C23 and C++23 only allow identifiers to start with a Unicode XID_START character, which excludes $. And with older standards, it was just Latin letters, the underscore, and explicit \u escapes.
If you look in the project's pedantic.cmake, you'll find a add_c_and_cxx_compile_options("-Wno-dollar-in-identifier-extension") just to suppress warnings about this.
Once you strip out all the helper code for tuples and args, it's really not the worst. Made sense to me on the first read. Sensible naming and not that much metaprogramming indirection going on, thank god.
Or maybe I am too brainwashed by C++ at this point.
I'm sorry I know this is horrific but I still love it. This looks like a better version of Boost Lambda2. I would potentially maybe replace `$` with `_` before using this (which should be easy as a layer) like Boost::Lambda2 but otherwise I'm excited to use it. Not that I would use anything like this in production, but it looks too fun not to play around with.
huh. very cute. in the past, i had an idea for terser lambda syntax, similar to C#'s expression body functions - which i did end up implementing in clang:
auto sum = [](auto a, auto b): a+b;
but this is something else. i didn't think i'd like it at first, but actually i think i might be coming around to it. the.. dollar syntax is regrettable, although it's not a show stopper.
Pretty cool. I was wondering what kind of arcane magic they used to get $xxx working, since $ is not a standard identifier char... then I realised they straight up define $arg, $call, etc as constants (makes a lot of sense). And $ really is not an identifier char by the Standard, but evidently some compilers accept it.
I started out trying to write something like the OP, but changed direction when I convinced myself there would have been no sane way to implement member call syntax. I honestly can't decide if it's cursed or genuinely useful (minus the unicode name, that's cursed).
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