Document fully-qualified syntax in as' keyword doc
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library/std/src/keyword_docs.rs
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| @@ -24,6 +24,13 @@ | |||
| /// (`u8`, `bool`, `str`, pointers, ...) whereas `From` and `Into` also works with types like | |||
| /// `String` or `Vec`. | |||
| /// | |||
| /// You'll also find with `From` and `Into`, and indeed all traits, that `as` is used for the | |||
| /// _fully qualified syntax_, a means of clarifying ambiguous method calls. If you have a type which | |||
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I would use fully qualified path here over syntax because that's more precise and what The Reference and rustc calls it.
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Ah ok I couldn't find it in the reference. It's called syntax in the rust book, but I certainly like path better.
library/std/src/keyword_docs.rs
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| @@ -24,6 +24,13 @@ | |||
| /// (`u8`, `bool`, `str`, pointers, ...) whereas `From` and `Into` also works with types like | |||
| /// `String` or `Vec`. | |||
| /// | |||
| /// You'll also find with `From` and `Into`, and indeed all traits, that `as` is used for the | |||
| /// _fully qualified syntax_, a means of clarifying ambiguous method calls. If you have a type which | |||
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This is not just for method calls, it's for all three kinds of associated item: Function, constant and type.
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| /// _fully qualified path_, a means of clarifying ambiguous method calls, constants, and types. | ||
| /// If you have a type which implements two traits with identical method names (e.g. | ||
| /// `Into<u32>::into` and `Into<u64>::into`), you can clarify which method you'll use with | ||
| /// `<MyThing as Into<u32>>::into(my_thing)`. This is quite verbose, but fortunately, Rust's type |
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Are there any other std traits where this is commonly needed? A small downside with this example is that this is something that should just be written u32::from(my_thing) 🙂
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