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Improve formatting and update info in "method lookup" section

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Camelid 2021-04-09 14:25:18 -07:00 committed by Joshua Nelson
parent ee9bb8e48d
commit 0822830537
1 changed files with 12 additions and 21 deletions
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33
src/method-lookup.md
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@ -6,18 +6,11 @@ file provides an overview of the process. More detailed notes are in
the code itself, naturally. the code itself, naturally.
One way to think of method lookup is that we convert an expression of One way to think of method lookup is that we convert an expression of
the form: the form `receiver.method(...)` into a more explicit [fully-qualified syntax][]
(formerly called [UFCS][]):
```rust,ignore - `Trait::method(ADJ(receiver), ...)` for a trait call
receiver.method(...) - `ReceiverType::method(ADJ(receiver), ...)` for an inherent method call
```
into a more explicit [UFCS] form:
```rust,ignore
Trait::method(ADJ(receiver), ...) // for a trait call
ReceiverType::method(ADJ(receiver), ...) // for an inherent method call
```
Here `ADJ` is some kind of adjustment, which is typically a series of Here `ADJ` is some kind of adjustment, which is typically a series of
autoderefs and then possibly an autoref (e.g., `&**receiver`). However autoderefs and then possibly an autoref (e.g., `&**receiver`). However
@ -37,6 +30,7 @@ probe phase produces a "pick" (`probe::Pick`), which is designed to be
cacheable across method-call sites. Therefore, it does not include cacheable across method-call sites. Therefore, it does not include
inference variables or other information. inference variables or other information.
[fully-qualified syntax]: https://doc.rust-lang.org/nightly/book/ch19-03-advanced-traits.html#fully-qualified-syntax-for-disambiguation-calling-methods-with-the-same-name
[UFCS]: https://github.com/rust-lang/rfcs/blob/master/text/0132-ufcs.md [UFCS]: https://github.com/rust-lang/rfcs/blob/master/text/0132-ufcs.md
[probe]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_typeck/check/method/probe/ [probe]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_typeck/check/method/probe/
[confirm]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_typeck/check/method/confirm/ [confirm]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_typeck/check/method/confirm/
@ -51,12 +45,10 @@ until it cannot be deref'd anymore, as well as applying an optional
"unsize" step. So if the receiver has type `Rc<Box<[T; 3]>>`, this "unsize" step. So if the receiver has type `Rc<Box<[T; 3]>>`, this
might yield: might yield:
```rust,ignore 1. `Rc<Box<[T; 3]>>`
Rc<Box<[T; 3]>> 2. `Box<[T; 3]>`
Box<[T; 3]> 3. `[T; 3]`
[T; 3] 4. `[T]`
[T]
```
### Candidate assembly ### Candidate assembly
@ -99,10 +91,9 @@ So, let's continue our example. Imagine that we were calling a method
that defines it with `&self` for the type `Rc<U>` as well as a method that defines it with `&self` for the type `Rc<U>` as well as a method
on the type `Box` that defines `Foo` but with `&mut self`. Then we on the type `Box` that defines `Foo` but with `&mut self`. Then we
might have two candidates: might have two candidates:
```text
&Rc<Box<[T; 3]>> from the impl of `Foo` for `Rc<U>` where `U=Box<[T; 3]> - `&Rc<Box<[T; 3]>>` from the impl of `Foo` for `Rc<U>` where `U=Box<[T; 3]>`
&mut Box<[T; 3]>> from the inherent impl on `Box<U>` where `U=[T; 3]` - `&mut Box<[T; 3]>>` from the inherent impl on `Box<U>` where `U=[T; 3]`
```
### Candidate search ### Candidate search