Clippy lint · Pedantic · checked with Clippy 0.1.99

clippy::large_digit_groups: digit groups should be smaller

What it meansWarns if the digits of an integral or floating-point constant are grouped into groups that are too large. It is in the pedantic group and off by default.

What you see

warning: digit groups should be smaller
 --> main.rs:3:14
  |
3 | let x: u64 = 6186491_8973511;
  |              ^^^^^^^^^^^^^^^ help: consider: `61_864_918_973_511`
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#large_digit_groups
  = note: `-W clippy::large-digit-groups` implied by `-W clippy::pedantic`

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?

Negatively impacts readability.

Stricter lints with some false positives. Off by default; opt in with clippy::pedantic.

How to fix it

Clippy does not fix this one automatically (its suggestion may change behaviour, so it only shows it). Change the code by hand:

Flagged

let x: u64 = 6186491_8973511;

Turn it off, or on

It is off by default. To use it, set it to warn or deny:

Whole crate (Cargo.toml)

[lints.clippy]
large_digit_groups = "warn"

In code

#![warn(clippy::large_digit_groups)]

One run

cargo clippy -- -W clippy::large-digit-groups

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.

Pedanticgroup

allowdefault level

nofixed by cargo clippy --fix

pre 1.29.0added in Rust

Clippy's own documentation

What it does

Warns if the digits of an integral or floating-point constant are grouped into groups that are too large.

Why is this bad?

Negatively impacts readability.

Example

let x: u64 = 6186491_8973511;

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

Up next

Also worth your time

Did this answer your question?