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Include a link to count_ones in the docs for uN::count_zeros [docs only] #151274

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Merged
rust-bors merged 1 commit into from
Jan 18, 2026
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Include a link to count_ones in the docs for uN::count_zeros [docs only] #151274

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22 changes: 22 additions & 0 deletions library/core/src/num/uint_macros.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -93,6 +93,28 @@ macro_rules! uint_impl {
#[doc = concat!("let max = ", stringify!($SelfT),"::MAX;")]
/// assert_eq!(max.count_zeros(), 0);
/// ```
///
/// This is heavily dependent on the width of the type, and thus
/// might give surprising results depending on type inference:
/// ```
/// # fn foo(_: u8) {}
/// # fn bar(_: u16) {}
/// let lucky = 7;
/// foo(lucky);
/// assert_eq!(lucky.count_zeros(), 5);
/// assert_eq!(lucky.count_ones(), 3);
///
/// let lucky = 7;
/// bar(lucky);
/// assert_eq!(lucky.count_zeros(), 13);
/// assert_eq!(lucky.count_ones(), 3);
/// ```
/// You might want to use [`Self::count_ones`] instead, or emphasize
/// the type you're using in the call rather than method syntax:
/// ```
/// let small = 1;
#[doc = concat!("assert_eq!(", stringify!($SelfT), "::count_zeros(small), ", stringify!($BITS_MINUS_ONE) ,");")]
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "const_math", since = "1.32.0")]
#[must_use = "this returns the result of the operation, \
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