rust-lang/rust-clippy

Lint request: Prevent lifetimes that are only used for function output

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#1,874 opened on Jul 5, 2017

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 (9 comments) (0 reactions) (0 assignees)Rust (1,391 forks)batch import
A-lintL-correctnessS-needs-discussionT-middlegood first issue

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Description

The following:

fn lifetime<'a>() -> &'a str {
    "Why some people do that"
}

Can be more clearly written as this. Also, using 'static lifetime makes it clear that it was intended, especially in unsafe code where returning unbound lifetime may as well be a mistake.

fn lifetime() -> &'static str {
    "Why some people do that"
}

Contributor guide

Research direction
Implement a new lint that detects lifetimes that appear only in the return type of a function, suggesting the use of 'static instead. Study existing lints like 'needless lifetimes' for implementation patterns.
Tech stack
rust
Domain
backend
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
Rust
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70