clippy::explicit_iter_loop: Checks for loops on x.iter() where &x will do, and suggests the latter

// with `y` a `Vec` or slice:
for x in y.iter() {
    // ..
}

for x in &y {
    // ..
}

[lints.clippy]
explicit_iter_loop = "warn"

#![warn(clippy::explicit_iter_loop)]

cargo clippy -- -W clippy::explicit-iter-loop

Clippy's own documentation

What it does

Checks for loops on x.iter() where &x will do, and suggests the latter.

Why is this bad?

Readability.

Known problems

False negatives. We currently only warn on some known types.

Example

// with `y` a `Vec` or slice:
for x in y.iter() {
    // ..
}

Use instead:

for x in &y {
    // ..
}

Configuration

• enforce-iter-loop-reborrow: Whether to recommend using implicit into iter for reborrowed values.

Example

let mut vec = vec![1, 2, 3];
let rmvec = &mut vec;
for _ in rmvec.iter() {}
for _ in rmvec.iter_mut() {}

Use instead:

let mut vec = vec![1, 2, 3];
let rmvec = &mut vec;
for _ in &*rmvec {}
for _ in &mut *rmvec {}

(default: false)

From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.

Related lints

• too_many_linesChecks for functions with a large amount of lines
• missing_errors_docChecks the doc comments of publicly visible functions that return a Result type and warns if there is no # Errors section
• must_use_candidateChecks for public functions that have no #[must_use] attribute, but return something not already marked must-use, have no mutable arg and mutate no statics
• expl_impl_clone_on_copyChecks for explicit Clone implementations for Copy types
• explicit_deref_methodsexplicit `deref` method call
• explicit_into_iter_loopChecks for loops on y.into_iter() where y will do, and suggests the latter
• filter_map_nextcalled `filter_map(..).next()` on an `Iterator`
• flat_map_optionused `flat_map` where `filter_map` could be used instead
• float_cmpstrict comparison of `f32` or `f64`

All 847 Clippy lints · Rust compiler errors · Cargo.toml checker