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haeffin · 2017-10-29 17:39:08

Why do you say (3) does not exist? C++ has it (and it's one of the main reason why, at the moment, I wouldn't use Rust to do the things I do).

sqeaky | karma 2830 | avg karma 1.71 · | 2017-02-21 13:04:34

I think that is his point, he thinks Rust and C++ cannot do this. But is the default in C++ and well done in Rust.

Thaxll | karma 4756 | avg karma 1.87 · | 2024-03-25 20:01:39

So it's absent from every language but Rust?

leshow | karma 2029 | avg karma 1.87 · | 2019-08-12 15:45:45

All of those languages have a runtime that enables this sort of thing. That's not the case in Rust. It's a bit of an unfair thing to knock it for, given the restrictions.

tus88 | karma 566 | avg karma 0.81 · | 2020-03-09 20:20:03

You mean there is no compile time way to accomplish that? Doesn't sound very Rust-like.

josephg | karma 16849 | avg karma 4.67 · | 2022-10-18 14:36:04

Nope! Rust doesn’t have function overloading like C++. What would that code look like in C++?

(Rust has operator overloading - but that’s not the same thing).

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CyberShadow | karma 1924 | avg karma 4.48 · | 2015-01-23 15:24:19+00:00

This is not an unique feature today, you can do the same in D and Rust and even C++14, I think.

adastra22 | karma 6858 | avg karma 2.11 · | 2022-05-23 15:11:22

Rust being the popular example. But even C++ has this with std::optional, for example.

est31 | karma 15854 | avg karma 4.44 · | 2021-02-05 19:50:07+00:00

You can do it non-properly in Rust as well, e.g. using unwraps, etc. but even then it's still way better than an UB-ridden component of a C++ codebase.

hoseja | karma 2536 | avg karma 1.08 · | 2020-08-20 07:02:53+00:00

TIL Rust doesn't have function overloading. But actually not sure whether this is a good or bad thing.

fzzzy | karma 1315 | avg karma 1.53 · | 2022-02-25 13:52:12

No. Rust does not have the equivalent of Object or void *.

jeremyjh | karma 8085 | avg karma 3.3 · | 2016-10-01 11:44:19+00:00

You are mistaken about rust. I can't think of a construct that is not an expression.

_RPM | karma 1029 | avg karma 1.11 · | 2016-04-26 19:58:52

I don't believe that it being written in Rust is a feature. The language it's written in is just an implementation detail.

leshow | karma 2029 | avg karma 1.87 · | 2020-09-22 02:34:33+00:00

The fact that there are options is my point: it's ambiguous. That's the reason there is no implementation for it in the std lib. You're absolutely free in Rust to define your own though.

nemothekid | karma 13576 | avg karma 4.48 · | 2024-01-10 22:04:04

This feels like a personal statement of familiarity rather than looking ahead to designing a language that has to be taught to next generation of software engineers. AFAIK, the only operator Rust introduces over C++ is the try operator (aka. ?) and match statements. Furthermore I can't imagine how someone could prefer

    &&auto my_closure = [&](int x, int y) { return x + y }

to just

    let my_closure = |x: int, y: int| { x + y }

C++ is the one that tries hard to standout.

StillBored | karma 6088 | avg karma 2.93 · | 2022-03-29 01:18:36

But the rust story is basically the same as the C story, which is use something other than the normal operators to do your arithmetic.

There are tons of checked_add()_sub/_mul macros or functions floating around. At least in C++ one could override the global operators if needed.

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wyager | karma 8769 | avg karma 1.68 · | 2016-12-29 17:23:43+00:00

Rust has very limited higher-order functions. True functional-style HOFs require passing around arbitrarily-sized heap closures, which doesn't work with rust's memory model. You cannot, for example, have a vector of functions in rust. You can sort of get it with boxed closures, but it's very inconvenient compared to in any of the languages I mentioned. That's why I didn't include it.

elbear | karma 649 | avg karma 1.05 · | 2024-04-06 08:49:57

I've seen it in Python. Not in Rust, because I haven't worked with Rust.

nicoburns | karma 22847 | avg karma 3.29 · | 2021-03-01 23:58:32

This is where Rust's decision to keep such functions out of the standard library entirely starts to look pretty smart.

oblio | karma 25694 | avg karma 2.47 · | 2021-04-25 12:59:36+00:00

> Rust doesn't have variadic functions

By design or because nobody has implemented them, yet?

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