[nananana9]

I took some shit in the comments yesterday for suggesting "you can do it with a few lines of standard C++" to another similar thread, but yet again here we are.

Defer takes 10 lines to implement in C++. [1]

You don't have to wait 50 years for a committee to introduce basic convenience features, and you don't have to use non-portable extensions until they do (and in this case the __attribute__((cleanup)) has no equivalent in MSVC), if you use a remotely extensible language.

[1] https://www.gingerbill.org/article/2015/08/19/defer-in-cpp/

[mort96]

Why is this a relevant comment? We're talking about C, not C++. If you wanted to suggest using an alternative language, you're probably better off recommending Zig: defer takes 0 lines to implement there, and it's closer to C than what C++ is.

[nananana9]

Everyone reading this (you included) knows full well that unlike Zig/Rust/Odin/whatever, C++ has the special property that you can quite literally* write C code in it, AND you can implement whatever quality of life fixes you need with targeted usage of RAII+templates+macros (defer, bounds checked accesses, result types, whatever).

My comment is targeted towards the programmer who is excited about features like this - you can add an extra two characters to your filename and trivially implement those improvements (and more) yourself, without any alterations to your codebase or day to day programming style.

[mort96]

C in C++ is a pretty terrible experience. The differences your asterisk alludes to are actually quite significant in practice:

C++ doesn't let you implicitly cast from void* to other pointer types. This breaks the way you typically heap-allocate variables in C: instead of 'mytype *foo = malloc(sizeof(*foo))', you have to write 'mytype *foo = (mytype *)malloc(sizeof(*foo))'. This adds a non-trivial amount of friction to something you do every handful of lines.

String literals in C++ are 'const char *' instead of 'char *'. While this is more technically correct, it means you have to add casts to 'char *' all over the place. Plenty of C APIs are really not very ergonomic when string literals aren't 'char *'.

And the big one: C++ doesn't have C's struct literals. Lots of C APIs are super ergonomic if you call them like this:

    some_function(&(struct params) {
        .some_param = 10,
        .other_param = 20,
    });

You can't do that in C++. C++ has other features (such as its own, different kind of aggregate initialization with designated initializers, and the ability for temporaries to be treated as const references) which make C++ APIs nice to work with from C++, but C APIs based around the assumption that you'll be using struct literals aren't nice to use from C++.

If you wanna use C, use C. C is a much better C than C++ is.

[nananana9]

I'll give you the last bullet you missed, you're also giving up the { [3] = ..., [5] = ... } array initializer syntax.

I like both these syntax-es (syntacies? synticies?) and I hope they make their way to C++, but if we're honestly evaluating features -- take their utility, multiply it by 100 and in my book it's still losing out against either defer or slices/span types.

If you disagree with this, then your calculus for feature utility is completely different than mine. I suspect for most people that's not the case, and most of the time the reason to pick C over C++ is ideological, not because of these 2 pieces of syntax sugar.

"I like it" is a good enough reason to use something, my original comment is to the person who wants to use C but gets excited about features like this - I don't know how many of those people are aware of how trivially most of these things can be accomplished in C++.

[mort96]

I write way more C++ than I write C. I was not comparing C and C++ in terms of which language is better or has more significant features. I was evaluating your suggestion to write C in C++ and get defer that way.

[BoredomIsFun]

> C in C++ is a pretty terrible experience

No I think, it the other way around, a fantastic experience; yes, you miss certain features of C, but instead you get massive benefits of C++ - above-mentioned defer, that'd work on any moderrn C++ compiler, constexpr's, a strategic use of STL while prototyping, templates etc.

> C++ doesn't let you implicitly cast from void* to other pointer types

It does, but that is not a good thing IMO anyway.

> Plenty of C APIs are really not very ergonomic when string literals aren't 'char '.

Examples? In my experience most C libraries have const char in their signatures whenever it makes sense.

> C is a much better C than C++ is.

Nonsense.