num-rational

chore: Release num-rational version 0.4.2

• Upgrade to 2021 edition, MSRV 1.60
• Add Ratio::approximate_float_unsigned to convert FloatCore types to unsigned
• Add const ZERO and ONE, and implement num_traits::ConstZero and ConstOne
• Add Ratio::into_raw to deconstruct the numerator and denominator

Contributors: @cuviper, @Enyium, @flavioroth, @waywardmonkeys

• Fewer clone calls are used when reducing a new Ratio<T>.
• Conversions to floating point are better at avoiding underflow.
• Ratio<T> now implements Default, returning a zero value.

Contributors: @cuviper, @lemmih, @MattX

• The optional num-bigint dependency is now 0.4.
• The Rational alias for Ratio<usize> is now deprecated. It is recommended to use specific type sizes for numeric computation, like Rational32 and Rational64.

Contributors: @cuviper, @vks

• Fix always rebuilding with --remap-path-prefix

Contributors: @Nemo157

• Handle to_f64() with raw division by zero.
• Better document panic behaviour.
• Clarify the license specification as "MIT OR Apache-2.0".

Contributors: @cuviper, @zetok

Enhancements

• Ratio now implements ToPrimitive.
• Ratio now implements additional formatting traits:
  • Binary, Octal, LowerHex, UpperHex, LowerExp, UpperExp
• The Pow implementations have been expanded.
  • Pow<BigInt> and Pow<BigUint> are now implemented.
  • Pow<_> for &Ratio<T> now uses &T: Pow.
  • The inherent pow method now uses &T: Pow.

Breaking Changes

• num-rational now requires Rust 1.31 or greater.
  • The "i128" opt-in feature was removed, now always available.
• The "num-bigint-std" feature replaces "bigint" with std enabled.
  • The "num-bigint" feature without std uses alloc on Rust 1.36+.

Contributors: @cuviper, @MattX, @maxbla

• Fixed CheckedDiv when both dividend and divisor are 0.
• Fixed CheckedDiv with min_value() numerators.

• Ratio now performs earlier reductions to avoid overflow with +-*/% operators.
• Ratio::{new_raw, numer, denom} are now const fn for Rust 1.31 and later.
• Updated the autocfg build dependency to 1.0.

Contributors: @cuviper, @dingelish, @jimbo1qaz, @maxbla

• Ratio now implements Zero::set_zero and One::set_one.

Contributors: @cuviper, @ignatenkobrain, @vks

• Maintenance release to fix html_root_url.

Enhancements

• Ratio now implements One::is_one and the Inv trait.
• Ratio now implements Sum and Product.
• Ratio now supports i128 and u128 components with Rust 1.26+.
• Ratio now implements the Pow trait.

Breaking Changes

• num-rational now requires rustc 1.15 or greater.
• There is now a std feature, enabled by default, along with the implication that building without this feature makes this a #![no_std] crate. A few methods now require FloatCore instead of Float.
• The serde dependency has been updated to 1.0, and rustc-serialize is no longer supported by num-rational.
• The optional num-bigint dependency has been updated to 0.2, and should be enabled using the bigint-std feature. In the future, it may be possible to use the bigint feature with no_std.

Contributors: @clarcharr, @cuviper, @Emerentius, @robomancer-or, @vks

• Maintenance release to update dependencies.

• num-rational now has its own source repository at rust-num/num-rational.
• Ratio now implements CheckedAdd, CheckedSub, CheckedMul, and CheckedDiv.
• Ratio now implements AddAssign, SubAssign, MulAssign, DivAssign, and RemAssign with either Ratio or an integer on the right side. The non-assignment operators now also accept integers as an operand.
• Ratio operators now make fewer clone() calls.

Thanks to @c410-f3r, @cuviper, and @psimonyi for their contributions!