Clippy lint · Complexity · checked with Clippy 0.1.99

clippy::map_all_any_identity: Checks for usage of .map(…), followed by .all(identity) or .any(identity)

What it meansChecks for usage of .map(…), followed by .all(identity) or .any(identity). It is in the complexity group and warns by default.

Does it matter?

The .all(…) or .any(…) methods can be called directly in place of .map(…).

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

let e1 = v.iter().map(|s| s.is_empty()).all(|a| a);
let e2 = v.iter().map(|s| s.is_empty()).any(std::convert::identity);

Write this instead

let e1 = v.iter().all(|s| s.is_empty());
let e2 = v.iter().any(|s| s.is_empty());

Turn it off, or on

Allow it where it does not fit your code, as narrowly as you can:

On one item

#[allow(clippy::map_all_any_identity)]
fn my_function() { /* ... */ }

Whole crate (Cargo.toml)

[lints.clippy]
map_all_any_identity = "allow"

One run

cargo clippy -- -A clippy::map-all-any-identity

The [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.

Complexitygroup

warndefault level

yesfixed by cargo clippy --fix

1.84.0added in Rust

Clippy's own documentation

What it does

Checks for usage of .map(…), followed by .all(identity) or .any(identity).

Why is this bad?

The .all(…) or .any(…) methods can be called directly in place of .map(…).

Example

let e1 = v.iter().map(|s| s.is_empty()).all(|a| a);
let e2 = v.iter().map(|s| s.is_empty()).any(std::convert::identity);

Use instead:

let e1 = v.iter().all(|s| s.is_empty());
let e2 = v.iter().any(|s| s.is_empty());

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

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