Add new methods for Rust 1.97

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       matrix:
         rust: [
-          1.94.0, # MSRV
+          1.97.0, # MSRV
           stable,
           beta,
           nightly,
@@ -52,7 +52,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.94.0
+      - uses: dtolnay/rust-toolchain@1.97.0
         with:
           components: rustfmt
       - run: cargo fmt --all --check

Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "num-primitive"
-version = "0.3.8"
+version = "0.3.9"
 description = "Traits for primitive numeric types"
 repository = "https://github.com/rust-num/num-primitive"
 license = "MIT OR Apache-2.0"
 keywords = ["generic", "mathematics", "numerics", "primitive"]
 categories = ["algorithms", "science", "no-std"]
 edition = "2024"
-rust-version = "1.94"
+rust-version = "1.97"
 
 [package.metadata.release]
 allow-branch = ["main"]

README.md

@@ -1,9 +1,9 @@
 # num-primitive
 
 [![crate](https://img.shields.io/crates/v/num-primitive.svg)](https://crates.io/crates/num-primitive)
-[![minimum rust 1.94](https://img.shields.io/badge/rust-1.94+-blue.svg)](https://rust-lang.github.io/rfcs/2495-min-rust-version.html)
+[![minimum rust 1.97](https://img.shields.io/badge/rust-1.97+-blue.svg)](https://rust-lang.github.io/rfcs/2495-min-rust-version.html)
 [![documentation](https://docs.rs/num-primitive/badge.svg)](https://docs.rs/num-primitive)
-[![build status](https://github.com/rust-num/num-primitive/workflows/CI/badge.svg)](https://github.com/rust-num/num-primitive/actions)
+[![build status](https://github.com/rust-num/num-primitive/actions/workflows/ci.yml/badge.svg)](https://github.com/rust-num/num-primitive/actions/workflows/ci.yml)
 
 Traits for primitive numeric types in Rust.
 

RELEASES.md

@@ -1,3 +1,13 @@
+# Release 0.3.9 (2026-07-09)
+
+- Updated to MSRV 1.97.
+- Added `PrimitiveInteger::{highest_one,lowest_one}`.
+- Added `PrimitiveInteger::{isolate_highest_one,isolate_lowest_one}`.
+- Added `PrimitiveUnsigned::bit_width`.
+- Added `NonZeroPrimitiveInteger::{highest_one,lowest_one}`.
+- Added `NonZeroPrimitiveInteger::{isolate_highest_one,isolate_lowest_one}`.
+- Added `NonZeroPrimitiveUnsigned::bit_width`.
+
 # Release 0.3.8 (2026-07-09)
 
 - Added traits for `NonZero`-wrapped primitive integers: `NonZeroPrimitiveInteger`,

src/integer.rs

@@ -280,6 +280,9 @@ pub trait PrimitiveInteger:
     /// Parses an integer from a string slice with digits in a given base.
     fn from_str_radix(src: &str, radix: u32) -> Result<Self, ParseIntError>;
 
+    /// Returns the index of the highest bit set to one in `self`, or `None` if `self` is `0`.
+    fn highest_one(self) -> Option<u32>;
+
     /// Returns the logarithm of the number with respect to an arbitrary base, rounded down.
     fn ilog(self, base: Self) -> u32;
 
@@ -289,6 +292,12 @@ pub trait PrimitiveInteger:
     /// Returns the base 2 logarithm of the number, rounded down.
     fn ilog2(self) -> u32;
 
+    /// Returns `self` with only the most significant bit set, or `0` if the input is `0`.
+    fn isolate_highest_one(self) -> Self;
+
+    /// Returns `self` with only the least significant bit set, or `0` if the input is `0`.
+    fn isolate_lowest_one(self) -> Self;
+
     /// Returns the square root of the number, rounded down.
     fn isqrt(self) -> Self;
 
@@ -298,6 +307,9 @@ pub trait PrimitiveInteger:
     /// Returns the number of leading zeros in the binary representation of `self`.
     fn leading_zeros(self) -> u32;
 
+    /// Returns the index of the lowest bit set to one in `self`, or `None` if `self` is `0`.
+    fn lowest_one(self) -> Option<u32>;
+
     /// Calculates `self + rhs`. Returns a tuple of the addition along with a boolean indicating
     /// whether an arithmetic overflow would occur.
     fn overflowing_add(self, rhs: Self) -> (Self, bool);
@@ -707,9 +719,21 @@ pub trait NonZeroPrimitiveInteger:
     /// Returns the contained value as a primitive type.
     fn get(self) -> Self::Integer;
 
+    /// Returns the index of the highest bit set to one in `self`.
+    fn highest_one(self) -> u32;
+
+    /// Returns `self` with only the most significant bit set.
+    fn isolate_highest_one(self) -> Self;
+
+    /// Returns `self` with only the least significant bit set.
+    fn isolate_lowest_one(self) -> Self;
+
     /// Returns the number of leading zeros in the binary representation of `self`.
     fn leading_zeros(self) -> u32;
 
+    /// Returns the index of the lowest bit set to one in `self`.
+    fn lowest_one(self) -> u32;
+
     /// Creates a non-zero if the given value is not zero.
     fn new(n: Self::Integer) -> Option<Self>;
 
@@ -767,12 +791,16 @@ macro_rules! impl_integer {
                 fn count_ones(self) -> u32;
                 fn count_zeros(self) -> u32;
                 fn div_euclid(self, rhs: Self) -> Self;
+                fn highest_one(self) -> Option<u32>;
                 fn ilog(self, base: Self) -> u32;
                 fn ilog10(self) -> u32;
                 fn ilog2(self) -> u32;
+                fn isolate_highest_one(self) -> Self;
+                fn isolate_lowest_one(self) -> Self;
                 fn isqrt(self) -> Self;
                 fn leading_ones(self) -> u32;
                 fn leading_zeros(self) -> u32;
+                fn lowest_one(self) -> Option<u32>;
                 fn overflowing_add(self, rhs: Self) -> (Self, bool);
                 fn overflowing_div(self, rhs: Self) -> (Self, bool);
                 fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool);
@@ -854,7 +882,11 @@ macro_rules! impl_integer {
                 fn checked_pow(self, other: u32) -> Option<Self>;
                 fn count_ones(self) -> NonZero<u32>;
                 fn get(self) -> Self::Integer;
+                fn highest_one(self) -> u32;
+                fn isolate_highest_one(self) -> Self;
+                fn isolate_lowest_one(self) -> Self;
                 fn leading_zeros(self) -> u32;
+                fn lowest_one(self) -> u32;
                 fn saturating_mul(self, other: Self) -> Self;
                 fn saturating_pow(self, other: u32) -> Self;
                 fn trailing_zeros(self) -> u32;

src/unsigned.rs

@@ -54,6 +54,10 @@ pub trait PrimitiveUnsigned:
     /// Computes the absolute difference between `self` and `other`.
     fn abs_diff(self, other: Self) -> Self;
 
+    /// Returns the minimum number of bits required to represent `self`.
+    /// This method returns zero if `self` is zero.
+    fn bit_width(self) -> u32;
+
     /// Calculates `self` − `rhs` − `borrow` and returns a tuple
     /// containing the difference and the output borrow.
     fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool);
@@ -185,6 +189,9 @@ pub trait NonZeroPrimitiveUnsigned:
     /// For `core::num::NonZero<T>`, this is `NonZero<T::Signed>`.
     type NonZeroSigned: NonZeroPrimitiveSigned;
 
+    /// Returns the minimum number of bits required to represent `self`.
+    fn bit_width(self) -> NonZero<u32>;
+
     /// Returns the bit pattern of `self` reinterpreted as a signed integer of the same size.
     fn cast_signed(self) -> Self::NonZeroSigned;
 
@@ -224,6 +231,7 @@ macro_rules! impl_unsigned {
 
             forward! {
                 fn abs_diff(self, other: Self) -> Self;
+                fn bit_width(self) -> u32;
                 fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool);
                 fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool);
                 fn carrying_mul(self, rhs: Self, carry: Self) -> (Self, Self);
@@ -256,6 +264,7 @@ macro_rules! impl_unsigned {
             type NonZeroSigned = NonZero<$Signed>;
 
             forward! {
+                fn bit_width(self) -> NonZero<u32>;
                 fn cast_signed(self) -> Self::NonZeroSigned;
                 fn checked_add(self, other: Self::Integer) -> Option<Self>;
                 fn checked_next_power_of_two(self) -> Option<Self>;