Clippy lints / Pedantic
Clippy lint · Pedantic · checked with Clippy 0.1.99
clippy::similar_names: binding's name is too similar to existing binding
What it meansChecks for names that are very similar and thus confusing. In particular, the lint checks for names with a single character change. It does not warn about names that have a single additional character at the beginning nor the end; only insertions in the middle are considered. Note: this lint looks for similar names throughout each scope. To allow it, you need to allow it on the scope level, not on the name that is reported. It is in the pedantic group and off by default.
What you see
warning: binding's name is too similar to existing binding --> main.rs:4:5 | 4 | let checked_eap = something_else; | ^^^^^^^^^^^ | note: existing binding defined here --> main.rs:3:5 | 3 | let checked_exp = something; | ^^^^^^^^^^^ = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#similar_names = note: `-W clippy::similar-names` 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?
It’s hard to distinguish between names that differ only by a single character.
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. Change the code by hand:
Flagged
let checked_exp = something;
let checked_eap = something_else;
Write this instead
let orange = val;
let ornange = val2;
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]
similar_names = "warn"In code
#![warn(clippy::similar_names)]One run
cargo clippy -- -W clippy::similar-namesThe [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
Checks for names that are very similar and thus confusing. In particular, the lint checks for names with a single character change.
It does not warn about names that have a single additional character at the beginning nor the end; only insertions in the middle are considered.
Note: this lint looks for similar names throughout each scope. To allow it, you need to allow it on the scope level, not on the name that is reported.
Why is this bad?
It’s hard to distinguish between names that differ only by a single character.
Example
let checked_exp = something;
let checked_eap = something_else;
Example 2
let orange = val;
let ornange = val2;
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
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- self_only_used_in_recursion`self` is only used in recursion
- semicolon_if_nothing_returnedconsider adding a `;` to the last statement for consistent formatting
- should_panic_without_expectChecks for #[should_panic] attributes without specifying the expected panic message
- single_char_patternChecks for string methods that receive a single-character str as an argument, e.g., _.split("x")
- single_match_elseChecks for matches with two arms where an if let else will usually suffice
- stable_sort_primitiveused `sort` on primitive type `i32`
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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