Clippy lints / Style
Clippy lint · Style · checked with Clippy 0.1.99
clippy::is_digit_ascii_radix: use of `char::is_digit` with literal radix of 10
What it meansFinds usages of char::is_digit that can be replaced with is_ascii_digit or is_ascii_hexdigit. It is in the style group and warns by default.
What you see
warning: use of `char::is_digit` with literal radix of 10 --> main.rs:4:1 | 4 | c.is_digit(10); | ^^^^^^^^^^^^^^ help: try: `c.is_ascii_digit()` | = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#is_digit_ascii_radix = note: `#[warn(clippy::is_digit_ascii_radix)]` on by default
Real output of Clippy 0.1.99 (Rust 1.99) on the example below. Names and line numbers in yours will differ.
Does it matter?
is_digit(..) is slower and requires specifying the radix.
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
let c: char = '6';
c.is_digit(10);
c.is_digit(16);
Write this instead
let c: char = '6';
c.is_ascii_digit();
c.is_ascii_hexdigit();
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::is_digit_ascii_radix)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
is_digit_ascii_radix = "allow"One run
cargo clippy -- -A clippy::is-digit-ascii-radixThe [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
Finds usages of char::is_digit that
can be replaced with is_ascii_digit or
is_ascii_hexdigit.
Why is this bad?
is_digit(..) is slower and requires specifying the radix.
Example
let c: char = '6';
c.is_digit(10);
c.is_digit(16);
Use instead:
let c: char = '6';
c.is_ascii_digit();
c.is_ascii_hexdigit();
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
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All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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