struct and tuple literals

[nrc]

No description provided.

[nrc]

structs

Single line version: Path { field1, field2 }. Note spaces before and after {, before }, no trailing comma

Mutli-line version:

Path {
    field1,
    field2,
}

Note space before {, block indent, trailing comma.

Use the mutli-line version if the literal does not fit in the line, if the fields are not short (see #47), or if any of the field sub-expressions cover multliple lines. Otherwise use the single-line version.

[nrc]

tuple variants

Unit variants are trivial.

Struct variants should follow the guidelines for structs.

Tuple variants should follow the guidelines for function calls.

[nrc]

Functional record update

Does not get a trailing comma, is otherwise treated like any other field. There is no space after the ... E.g.,

Path {
    field1,
    field2,
    ..some_expr
}

[Luthaf]

Single line version: Path { field1, field2 }. Note spaces before and after {, before }, no trailing comma

I kinda dislike this, up to the point that it was my major friction point with rustfmt. I don't know how others feels about this, but I am commenting here so that this is taken in consideration =). I would be happy with this not being the default but being configurable.

To me, this have way to many spaces. I would prefer Path{field1, field2}, without the spaces. The only rationalisation I can get for this is that inline struct literals feels like constructors in C++, with the braces playing the role of parenthesis.

A version with a space before the left brace looks OK to me too: Path {field1, field2}, and it would look more like the multiline version.

[chriskrycho]

@Luthaf for a counterpoint, the most immediate predecessor for this is JavaScript's object types. It's common there to write the same kind of short structure that way there:

const field1 = 'whatever';
const field2 = 42;
const path = { field1, field2 };

I'd also note that this feels quite different from construction in C++ to me – and I want to be made more actively aware that there isn't any function call happening! – but that's just me. I think the specified default is a good default, but I certainly wouldn't be hostile to its being configurable either.

[joshtriplett]

On May 16, 2017 1:47:57 AM PDT, Luthaf ***@***.***> wrote: > Single line version: Path { field1, field2 }. Note spaces before and after {, before }, no trailing comma I kinda dislike this, up to the point that it was my major friction point with rustfmt. I don't know how others feels about this, but I am commenting here so that this is taken in consideration =). I would be happy with this not being the default but being configurable. To me, this have way to many spaces. I would prefer `Path{field1, field2}`, without the spaces. The only rationalisation I can get for this is that inline struct literals feels like constructors in C++, with the braces playing the role of parenthesis. A version with a space before the left brace looks OK to me too: `Path {field1, field2}`, and it would look more like the multiline version.

I find it jarring to see anything right next to a curly brace like this. And struct constructors have obvious analogues in other languages, using similar syntax.