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Sizeof is surprisingly difficult to parse in C
- wren6991 2mo ago> (everything here also applies to c2y's newly introduced _Countof) Stop the press, they're adding what? So I don't have to keep adding #define count_of(arr) (sizeof(arr) / sizeof(*arr)) to every codebase and living with its failure modes? I'm really loving C's character arc at the moment, where they keep going back to fix old problems instead of piling everything and the kitchen sink into the language.
- HexDecOctBin 2mo agoYeah, despite puritanical hand-wringing over C23, I do like both the discipline and the selectivity with WG14 has shows (and I say this as a card-carrying C++ hater). I do wish they will start looking into proper arrays since there is already a syntax for this can can be augmented semantically: int func (int arg[static 5])
- zbentley 2mo ago> I'm really loving C's character arc at the moment, where they keep going back to fix old problems Valid, but it does seem a bit Stockholm Syndrome to have this much rejoicing that your language added a builtin for getting the length of an array in 2026.
- pjmlp 2mo agoIf only they actually fixed arrays and strings properly. C23 and C2y have plenty of kitchen sink features.
- inigyou 2mo agoWait, they added a new operator and didn't fix that parsing stupidity by always requiring parentheses?
- adrian_b 2mo agoI assume that there would be a zillion of legacy C source files that would be broken by such a change.
- high_na_euv 2mo agoI feel like what you struggle with is expression parsing, not sizeof itself?
- glouwbug 2mo agoIt's a unary operator, kind of like ~ or !, which can apply to parenthesis (), until it meets a type, then the parenthesis are mandatory: int x; sizeof x; // okay sizeof (x); // okay sizeof int; // not okay sizeof (int); // okay It's a weird double rule to parse, but even worse, the strongest binding precedence typically doesn't like an alpha identifier at that point in the recursive descent, so you get weird rules like: read_prefix(): is peak() '!': ... is peak() '~": ... is alpha(peak()) maybe alpha is sizeof? wait, it wasn't sizeof? it was an identifier? long rewind is peak() '+': ... Something like @ would've been a good pick for sizeof. \ramble on (actually, better yet, it should've been used instead of & for taking the address). Imagine: int x; int* p = @x; \ramble off
- deleted 2mo ago[deleted]
- atiedebee 2mo agoIve actually toyed with the idea of having @ as a pointer dereference. It seems to make sense: you want to know what is at the address stored in p.