Clippy lints / Style
Clippy lint · Style · checked with Clippy 0.1.99
clippy::to_digit_is_some: Checks for .to_digit(..).is_some() on chars
What it meansChecks for .to_digit(..).is_some() on chars. It is in the style group and warns by default.
Does it matter?
This is a convoluted way of checking if a char is a digit. It’s more straight forward to use the dedicated is_digit method.
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 is_digit = c.to_digit(radix).is_some();
Write this instead
let is_digit = c.is_digit(radix);
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::to_digit_is_some)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
to_digit_is_some = "allow"One run
cargo clippy -- -A clippy::to-digit-is-someThe [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.
Settings in clippy.toml
msrv: The minimum rust version that the project supports. Defaults to the rust-version field in Cargo.toml
Clippy's own documentation
What it does
Checks for .to_digit(..).is_some() on chars.
Why is this bad?
This is a convoluted way of checking if a char is a digit. It’s
more straight forward to use the dedicated is_digit method.
Example
let is_digit = c.to_digit(radix).is_some();
can be written as:
let is_digit = c.is_digit(radix);
Configuration
-
msrv: The minimum rust version that the project supports. Defaults to therust-versionfield inCargo.toml(default:
current version)
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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