rust-lang / rust-lang/reference

Improve method selection to make short-circuiting clear

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Dominant language
Rust
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Description

Method resolution has two steps. We collect a list of types, then we go through that list and, for each type, look to see whether there's one or more matching methods. If we find multiple matching trait methods, that's an error. But otherwise, we stop if we find one.

What we don't do is continue down the list of types after finding a matching method. In PR #1394 this was brought up. We weren't happy with the fix, but this is something we should think about when reworking this language.

See also:

cc @ehuss

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Research direction

Start by reading the discussion in PR #1394 and the linked Rust Reference PR #1432 and issues #1018 and #718. Determine whether the intended outcome is a documentation clarification or a language-design change; this issue is done only when the agreed method-resolution behavior is recorded in the Reference or superseded by a decided design.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
documentation
Issue type
Documentation
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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