Clippy lints / Complexity
Clippy lint · Complexity · checked with Clippy 0.1.99
clippy::filter_next: Checks for usage of _.filter(_).next()
What it meansChecks for usage of _.filter(_).next(). It is in the complexity group and warns by default.
Does it matter?
Readability, this can be written more concisely as _.find(_).
Code that does something simple in a complicated way. 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
vec.iter().filter(|x| **x == 0).next();
Write this instead
vec.iter().find(|x| **x == 0);
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::filter_next)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
filter_next = "allow"One run
cargo clippy -- -A clippy::filter-nextThe [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 usage of _.filter(_).next().
Why is this bad?
Readability, this can be written more concisely as
_.find(_).
Example
vec.iter().filter(|x| **x == 0).next();
Use instead:
vec.iter().find(|x| **x == 0);
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
- too_many_argumentsChecks for functions with too many parameters
- clone_on_copyusing `clone` on type `u64` which implements the `Copy` trait
- type_complexityChecks for types used in structs, parameters and let declarations above a certain complexity threshold
- extra_unused_lifetimesthis lifetime isn't used in the function definition
- extra_unused_type_parametersChecks for type parameters in generics that are never used anywhere else
- filter_map_identityChecks for usage of filter_map(|x| x)
- flat_map_identityChecks for usage of flat_map(|x| x)
- get_last_with_lenaccessing last element with `x.get(x.len() - 1)`
- identity_opChecks for identity operations, e.g., x + 0
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
Up next
Related lintclippy::too_many_argumentsChecks for functions with too many parametersRead it next →Did this answer your question?