Clippy lints / Pedantic
Clippy lint · Pedantic · checked with Clippy 0.1.99
clippy::too_many_lines: Checks for functions with a large amount of lines
What it meansChecks for functions with a large amount of lines. It is in the pedantic group and off by default.
Does it matter?
Functions with a lot of lines are harder to understand due to having to look at a larger amount of code to understand what the function is doing. Consider splitting the body of the function into multiple functions.
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
fn im_too_long() {
println!("");
// ... 100 more LoC
println!("");
}
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]
too_many_lines = "warn"In code
#![warn(clippy::too_many_lines)]One run
cargo clippy -- -W clippy::too-many-linesThe [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
too-many-lines-threshold: The maximum number of lines a function or method can have
Clippy's own documentation
What it does
Checks for functions with a large amount of lines.
Why is this bad?
Functions with a lot of lines are harder to understand due to having to look at a larger amount of code to understand what the function is doing. Consider splitting the body of the function into multiple functions.
Example
fn im_too_long() {
println!("");
// ... 100 more LoC
println!("");
}
Configuration
-
too-many-lines-threshold: The maximum number of lines a function or method can have(default:
100)
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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- struct_excessive_boolsChecks for excessive use of bools in structs
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All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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