this post was submitted on 13 Aug 2023
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When returning an immutable reference to a private struct field. (On mobile and used vertical bars instead of a bunch of HTML codes)

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[–] heartlessevil@lemmy.one 2 points 2 years ago (2 children)

A vec and a string are basically the same thing (a series of bytes)

In the context of vectors I prefer my APIs to return an empty set rather than an None-option. This makes handling it much easier because you can still iterate over it, it just has nothing.

This might involve the compiler making an allocation of an empty array but most of them (gcc, ghc) will now what you are doing and optimize the null check on the empty array to a bool check.

[–] hallettj@beehaw.org 2 points 2 years ago

In the context of vectors I prefer my APIs to return an empty set rather than an None-option. This makes handling it much easier because you can still iterate over it, it just has nothing.

I can see that argument. But you can also iterate over an Option-wrapped response with something like for x in xs.into_iter().flatten() { ... }, and the Option gives you an extra bit of information that can be helpful in certain cases.

[–] anlumo@feddit.de 2 points 2 years ago

Vec::new is const and thus can’t allocate anyways.