Clippy lints / Pedantic
Clippy lint · Pedantic · checked with Clippy 0.1.99
clippy::verbose_bit_mask: Checks for bit masks that can be replaced by a call to trailing_zeros
What it meansChecks for bit masks that can be replaced by a call to trailing_zeros It is in the pedantic group and off by default.
Does it matter?
x.trailing_zeros() >= 4 is much clearer than x & 15 == 0
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
if x & 0b1111 == 0 { }
Write this instead
if x.trailing_zeros() >= 4 { }
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]
verbose_bit_mask = "warn"In code
#![warn(clippy::verbose_bit_mask)]One run
cargo clippy -- -W clippy::verbose-bit-maskThe [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
verbose-bit-mask-threshold: The maximum allowed size of a bit mask before suggesting to use ‘trailing_zeros’
Clippy's own documentation
What it does
Checks for bit masks that can be replaced by a call
to trailing_zeros
Why is this bad?
x.trailing_zeros() >= 4 is much clearer than x & 15 == 0
Example
if x & 0b1111 == 0 { }
Use instead:
if x.trailing_zeros() >= 4 { }
Configuration
-
verbose-bit-mask-threshold: The maximum allowed size of a bit mask before suggesting to use ‘trailing_zeros’(default:
1)
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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