diff options
Diffstat (limited to '')
| -rw-r--r-- | library/core/src/num/mod.rs | 76 |
1 files changed, 74 insertions, 2 deletions
diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs index f481399fd..311c5fa5b 100644 --- a/library/core/src/num/mod.rs +++ b/library/core/src/num/mod.rs @@ -3,6 +3,7 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::ascii; +use crate::error::Error; use crate::intrinsics; use crate::mem; use crate::ops::{Add, Mul, Sub}; @@ -57,6 +58,15 @@ pub use wrapping::Wrapping; #[cfg(not(no_fp_fmt_parse))] pub use dec2flt::ParseFloatError; +#[cfg(not(no_fp_fmt_parse))] +#[stable(feature = "rust1", since = "1.0.0")] +impl Error for ParseFloatError { + #[allow(deprecated)] + fn description(&self) -> &str { + self.__description() + } +} + #[stable(feature = "rust1", since = "1.0.0")] pub use error::ParseIntError; @@ -101,6 +111,9 @@ macro_rules! widening_impl { /// This returns the low-order (wrapping) bits and the high-order (overflow) bits /// of the result as two separate values, in that order. /// + /// If you also need to add a carry to the wide result, then you want + /// [`Self::carrying_mul`] instead. + /// /// # Examples /// /// Basic usage: @@ -136,6 +149,8 @@ macro_rules! widening_impl { /// additional amount of overflow. This allows for chaining together multiple /// multiplications to create "big integers" which represent larger values. /// + /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead. + /// /// # Examples /// /// Basic usage: @@ -155,6 +170,31 @@ macro_rules! widening_impl { )] /// ``` /// + /// This is the core operation needed for scalar multiplication when + /// implementing it for wider-than-native types. + /// + /// ``` + /// #![feature(bigint_helper_methods)] + /// fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) { + /// let mut carry = 0; + /// for d in little_endian_digits.iter_mut() { + /// (*d, carry) = d.carrying_mul(multiplicand, carry); + /// } + /// if carry != 0 { + /// little_endian_digits.push(carry); + /// } + /// } + /// + /// let mut v = vec![10, 20]; + /// scalar_mul_eq(&mut v, 3); + /// assert_eq!(v, [30, 60]); + /// + /// assert_eq!(0x87654321_u64 * 0xFEED, 0x86D3D159E38D); + /// let mut v = vec![0x4321, 0x8765]; + /// scalar_mul_eq(&mut v, 0xFEED); + /// assert_eq!(v, [0xE38D, 0xD159, 0x86D3]); + /// ``` + /// /// If `carry` is zero, this is similar to [`overflowing_mul`](Self::overflowing_mul), /// except that it gives the value of the overflow instead of just whether one happened: /// @@ -582,6 +622,38 @@ impl u8 { matches!(*self, b'0'..=b'9') } + /// Checks if the value is an ASCII octal digit: + /// U+0030 '0' ..= U+0037 '7'. + /// + /// # Examples + /// + /// ``` + /// #![feature(is_ascii_octdigit)] + /// + /// let uppercase_a = b'A'; + /// let a = b'a'; + /// let zero = b'0'; + /// let seven = b'7'; + /// let nine = b'9'; + /// let percent = b'%'; + /// let lf = b'\n'; + /// + /// assert!(!uppercase_a.is_ascii_octdigit()); + /// assert!(!a.is_ascii_octdigit()); + /// assert!(zero.is_ascii_octdigit()); + /// assert!(seven.is_ascii_octdigit()); + /// assert!(!nine.is_ascii_octdigit()); + /// assert!(!percent.is_ascii_octdigit()); + /// assert!(!lf.is_ascii_octdigit()); + /// ``` + #[must_use] + #[unstable(feature = "is_ascii_octdigit", issue = "101288")] + #[rustc_const_unstable(feature = "is_ascii_octdigit", issue = "101288")] + #[inline] + pub const fn is_ascii_octdigit(&self) -> bool { + matches!(*self, b'0'..=b'7') + } + /// Checks if the value is an ASCII hexadecimal digit: /// /// - U+0030 '0' ..= U+0039 '9', or @@ -623,7 +695,7 @@ impl u8 { /// /// - U+0021 ..= U+002F `! " # $ % & ' ( ) * + , - . /`, or /// - U+003A ..= U+0040 `: ; < = > ? @`, or - /// - U+005B ..= U+0060 ``[ \ ] ^ _ ` ``, or + /// - U+005B ..= U+0060 `` [ \ ] ^ _ ` ``, or /// - U+007B ..= U+007E `{ | } ~` /// /// # Examples @@ -936,8 +1008,8 @@ impl usize { /// assert_eq!(num.classify(), FpCategory::Normal); /// assert_eq!(inf.classify(), FpCategory::Infinite); /// assert_eq!(zero.classify(), FpCategory::Zero); -/// assert_eq!(nan.classify(), FpCategory::Nan); /// assert_eq!(sub.classify(), FpCategory::Subnormal); +/// assert_eq!(nan.classify(), FpCategory::Nan); /// ``` #[derive(Copy, Clone, PartialEq, Eq, Debug)] #[stable(feature = "rust1", since = "1.0.0")] |