Clippy lints / Style
Clippy lint · Style · checked with Clippy 0.1.99
clippy::while_let_on_iterator: Checks for while let expressions on iterators
What it meansChecks for while let expressions on iterators. It is in the style group and warns by default.
Does it matter?
Readability. A simple for loop is shorter and conveys the intent better.
Code that works but is not idiomatic Rust. Warns by default.
How to fix it
Clippy can fix this one for you: run cargo clippy --fix (add --allow-dirty if you have uncommitted changes). Review the diff before you commit.
Flagged
while let Some(val) = iter.next() {
..
}
Write this instead
for val in &mut iter {
..
}
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::while_let_on_iterator)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
while_let_on_iterator = "allow"One run
cargo clippy -- -A clippy::while-let-on-iteratorThe [lints] table needs Rust 1.74 or newer. In a workspace, put it under [workspace.lints.clippy] and add [lints] workspace = true to each member.
Clippy's own documentation
What it does
Checks for while let expressions on iterators.
Why is this bad?
Readability. A simple for loop is shorter and conveys
the intent better.
Example
while let Some(val) = iter.next() {
..
}
Use instead:
for val in &mut iter {
..
}
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
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- unusual_byte_groupingsWarns if hexadecimal or binary literals are not grouped by nibble or byte
- unwrap_or_defaultChecks for usages of the following functions with an argument that constructs a default value (e.g., Default::default or String::new): unwrap_or unwrap_or_else or_insert or_insert_with
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- write_literalThis lint warns about the use of literals as write!/writeln! args
- write_with_newlineThis lint warns when you use write!() with a format string that ends in a newline
- writeln_empty_stringThis lint warns when you use writeln!(buf, "") to print a newline
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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