[swift-evolution] [Discussion] Design guideline rule for `:`

[Dave Abrahams]

on Wed Jun 22 2016, Adrian Zubarev <swift-evolution at swift.org> wrote:

> Should there be a design guideline rule for colons : in Swift?
>
> I see people doing things like this:
>
> protocol A : B {}
>
> // VS.
>
> protocol A: B {}
> func foo<T : A>() -> T { … }
>
> // VS.
>
> func foo<T: A>() -> T { … }
> var value : Type
>
> // VS.
>
> var value: Type
> [key1 : value1, key2 : value2]
>
> // VS.
>
> [key1: value1, key2: value2]
> I prefer the second style, where there is no whitespace between lhs
> and the : symbol and there is also a whitespace after :. Example:
> something: somethingElse

The standard library uses " : " for conformances and inheritance, and 
": " for type annotation.  FWIW.

-- 
Dave