clippy::inline_trait_bounds: inline trait bounds used

What you see

warning: inline trait bounds used
 --> main.rs:3:7
  |
3 | fn foo<T: Clone>() {}
  |       ^^^^^^^^^^
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#inline_trait_bounds
  = note: requested on the command line with `-W clippy::inline-trait-bounds`
help: move bounds to a `where` clause
  |
3 - fn foo<T: Clone>() {}
3 + fn foo<T>() where T: Clone {}
  |

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?

Enforce a single style throughout a codebase. Avoid uncertainty about whether a bound should be inline or out-of-line (i.e. a where bound). Avoid complex inline bounds, which could make a function declaration more difficult to read.

Lints that forbid language features for specific codebases (no unwrap, no indexing...). Off by default; pick them one by one, never the whole group.

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

fn foo<T: Clone>() {}

Write this instead

fn foo<T>() where T: Clone {}

Turn it off, or on

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

[lints.clippy]
inline_trait_bounds = "warn"

#![warn(clippy::inline_trait_bounds)]

cargo clippy -- -W clippy::inline-trait-bounds

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.