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Comment by zozbot234 | Hacker News Reader

The thing is that 'return' is not very common either, because Rust has shorthand for returning at the end of a function :-P

I think the standard library ought to use slightly longer names since it's far less strictly bounded than the set of language keywords, so I'm fine with 'Option'. 'Vec' is a bit awkward from that POV, but then again 'Vector' would be a lot worse. 'Box' is also awkward in the same way but thinking about it, it's not easy to convey the notion "this value is behind a pointer" so you might as well use a conventional name and get it over with.

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Why not call it Pointer or Point?

A Box is not a pointer. It is an object with regular one-owner, no copies semantics. Semantically, it just breaks the object out so that it isn’t “internal” to whatever contains it (useful for keeping individual objects small or working around the requirement that a type have a known, finite size).

A pointer and a heap allocation are the obvious choice for implementing this, but the semantics are notably different than just being a pointer. Rust also does have pointer types which represent true pointers.

AFAICT, Box has exactly the same semantics as C++‘s unique_ptr.

Where it can have the same semantics, yes. But if you look at the details, not exactly. For example Box is not nullable, but a not-nullable C++ equivalent is hard to do given the rest of the language.

Good point on the nullability; yes, that is indeed different from std::unique_ptr.

In game or graphical development a Point struct/object is usually reserved for Cartesian coordinates. Pointer seems too long. C's use of "*" and "&" remain my favorite though beginners may have more difficulty understanding it, similarly to Rust's Box.

> 'Vec' is a bit awkward from that POV, but then again 'Vector' would be a lot worse

They should just have called it a List, and stopped the propagation of the erroneous belief that a variable-length sequence of things is a vector.

`List` usually refers to a linked list or similar. Vec has the important feature that it encapsulate a contiguous array, which matters in a languages like Rust.

Python is a very popular language where the list type is implemented as an array, and named a list. Calling these things vectors (C++, Rust) is unfortunate because you eventually want real vectors for working with matrices, and the behavior is different in that context.

As for linked lists, given modern processors and cache behavior, there are very few places where you ever want to chase pointers for a 1D data structure. It seems like a shame to lose a good name to a data structure that should now be avoided most of the time.

An array of references. Plus, Python has no way to consume a contiguous array directly.

If you do interoperate through FFI with code in C or similar, you will have to reach for numpy arrays, which are the typed, contiguous arrays of Python.

> `List` usually refers to a linked list or similar.

No, it doesn't. There are a handful of languages where this is true, and no reason other than language-specific practice to think that a list is implicitly a linked list. People always make this objection and it's honestly just bizarre.

Or - since lists call to mind a very specific data structure (linked lists) - they could have just called it Sequence.

A sequence does not contain duplicates. A vector can

Mathematical sequences totally can have duplicates. E.g. to take a popular example, the Fibonacci sequence starts: 0, 1, 1, ...

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