1 //! Definitions of `Saturating<T>`.
4 use crate::ops::{Add, AddAssign, BitAnd, BitAndAssign, BitOr, BitOrAssign};
5 use crate::ops::{BitXor, BitXorAssign, Div, DivAssign};
6 use crate::ops::{Mul, MulAssign, Neg, Not, Rem, RemAssign};
7 use crate::ops::{Shl, ShlAssign, Shr, ShrAssign, Sub, SubAssign};
9 /// Provides intentionally-saturating arithmetic on `T`.
11 /// Operations like `+` on `u32` values are intended to never overflow,
12 /// and in some debug configurations overflow is detected and results
13 /// in a panic. While most arithmetic falls into this category, some
14 /// code explicitly expects and relies upon saturating arithmetic.
16 /// Saturating arithmetic can be achieved either through methods like
17 /// `saturating_add`, or through the `Saturating<T>` type, which says that
18 /// all standard arithmetic operations on the underlying value are
19 /// intended to have saturating semantics.
21 /// The underlying value can be retrieved through the `.0` index of the
22 /// `Saturating` tuple.
27 /// #![feature(saturating_int_impl)]
28 /// use std::num::Saturating;
30 /// let max = Saturating(u32::MAX);
31 /// let one = Saturating(1u32);
33 /// assert_eq!(u32::MAX, (max + one).0);
35 #[unstable(feature = "saturating_int_impl", issue = "87920")]
36 #[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default, Hash)]
38 pub struct Saturating<T>(#[unstable(feature = "saturating_int_impl", issue = "87920")] pub T);
40 #[unstable(feature = "saturating_int_impl", issue = "87920")]
41 impl<T: fmt::Debug> fmt::Debug for Saturating<T> {
42 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
47 #[unstable(feature = "saturating_int_impl", issue = "87920")]
48 impl<T: fmt::Display> fmt::Display for Saturating<T> {
49 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
54 #[unstable(feature = "saturating_int_impl", issue = "87920")]
55 impl<T: fmt::Binary> fmt::Binary for Saturating<T> {
56 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
61 #[unstable(feature = "saturating_int_impl", issue = "87920")]
62 impl<T: fmt::Octal> fmt::Octal for Saturating<T> {
63 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
68 #[unstable(feature = "saturating_int_impl", issue = "87920")]
69 impl<T: fmt::LowerHex> fmt::LowerHex for Saturating<T> {
70 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
75 #[unstable(feature = "saturating_int_impl", issue = "87920")]
76 impl<T: fmt::UpperHex> fmt::UpperHex for Saturating<T> {
77 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
81 #[allow(unused_macros)]
82 macro_rules! sh_impl_signed {
83 ($t:ident, $f:ident) => {
84 // FIXME what is the correct implementation here? see discussion https://github.com/rust-lang/rust/pull/87921#discussion_r695870065
86 // #[unstable(feature = "saturating_int_impl", issue = "87920")]
87 // impl Shl<$f> for Saturating<$t> {
88 // type Output = Saturating<$t>;
91 // fn shl(self, other: $f) -> Saturating<$t> {
93 // Saturating(self.0.shr((-other & self::shift_max::$t as $f) as u32))
95 // Saturating(self.0.shl((other & self::shift_max::$t as $f) as u32))
99 // forward_ref_binop! { impl Shl, shl for Saturating<$t>, $f,
100 // #[unstable(feature = "saturating_int_impl", issue = "87920")] }
102 // #[unstable(feature = "saturating_int_impl", issue = "87920")]
103 // impl ShlAssign<$f> for Saturating<$t> {
105 // fn shl_assign(&mut self, other: $f) {
106 // *self = *self << other;
109 // forward_ref_op_assign! { impl ShlAssign, shl_assign for Saturating<$t>, $f }
111 #[unstable(feature = "saturating_int_impl", issue = "87920")]
112 impl Shr<$f> for Saturating<$t> {
113 type Output = Saturating<$t>;
116 fn shr(self, other: $f) -> Saturating<$t> {
118 Saturating(self.0.shl((-other & self::shift_max::$t as $f) as u32))
120 Saturating(self.0.shr((other & self::shift_max::$t as $f) as u32))
124 forward_ref_binop! { impl Shr, shr for Saturating<$t>, $f,
125 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
127 #[unstable(feature = "saturating_int_impl", issue = "87920")]
128 impl ShrAssign<$f> for Saturating<$t> {
130 fn shr_assign(&mut self, other: $f) {
131 *self = *self >> other;
134 forward_ref_op_assign! { impl ShrAssign, shr_assign for Saturating<$t>, $f }
138 macro_rules! sh_impl_unsigned {
139 ($t:ident, $f:ident) => {
140 #[unstable(feature = "saturating_int_impl", issue = "87920")]
141 impl Shl<$f> for Saturating<$t> {
142 type Output = Saturating<$t>;
145 fn shl(self, other: $f) -> Saturating<$t> {
146 Saturating(self.0.wrapping_shl(other as u32))
149 forward_ref_binop! { impl Shl, shl for Saturating<$t>, $f,
150 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
152 #[unstable(feature = "saturating_int_impl", issue = "87920")]
153 impl ShlAssign<$f> for Saturating<$t> {
155 fn shl_assign(&mut self, other: $f) {
156 *self = *self << other;
159 forward_ref_op_assign! { impl ShlAssign, shl_assign for Saturating<$t>, $f }
161 #[unstable(feature = "saturating_int_impl", issue = "87920")]
162 impl Shr<$f> for Saturating<$t> {
163 type Output = Saturating<$t>;
166 fn shr(self, other: $f) -> Saturating<$t> {
167 Saturating(self.0.wrapping_shr(other as u32))
170 forward_ref_binop! { impl Shr, shr for Saturating<$t>, $f,
171 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
173 #[unstable(feature = "saturating_int_impl", issue = "87920")]
174 impl ShrAssign<$f> for Saturating<$t> {
176 fn shr_assign(&mut self, other: $f) {
177 *self = *self >> other;
180 forward_ref_op_assign! { impl ShrAssign, shr_assign for Saturating<$t>, $f }
184 // FIXME (#23545): uncomment the remaining impls
185 macro_rules! sh_impl_all {
186 ($($t:ident)*) => ($(
187 //sh_impl_unsigned! { $t, u8 }
188 //sh_impl_unsigned! { $t, u16 }
189 //sh_impl_unsigned! { $t, u32 }
190 //sh_impl_unsigned! { $t, u64 }
191 //sh_impl_unsigned! { $t, u128 }
192 sh_impl_unsigned! { $t, usize }
194 //sh_impl_signed! { $t, i8 }
195 //sh_impl_signed! { $t, i16 }
196 //sh_impl_signed! { $t, i32 }
197 //sh_impl_signed! { $t, i64 }
198 //sh_impl_signed! { $t, i128 }
199 //sh_impl_signed! { $t, isize }
203 sh_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize }
205 // FIXME(30524): impl Op<T> for Saturating<T>, impl OpAssign<T> for Saturating<T>
206 macro_rules! saturating_impl {
208 #[unstable(feature = "saturating_int_impl", issue = "87920")]
209 impl Add for Saturating<$t> {
210 type Output = Saturating<$t>;
213 fn add(self, other: Saturating<$t>) -> Saturating<$t> {
214 Saturating(self.0.saturating_add(other.0))
217 forward_ref_binop! { impl Add, add for Saturating<$t>, Saturating<$t>,
218 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
220 #[unstable(feature = "saturating_int_impl", issue = "87920")]
221 impl AddAssign for Saturating<$t> {
223 fn add_assign(&mut self, other: Saturating<$t>) {
224 *self = *self + other;
227 forward_ref_op_assign! { impl AddAssign, add_assign for Saturating<$t>, Saturating<$t> }
229 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
230 impl AddAssign<$t> for Saturating<$t> {
232 fn add_assign(&mut self, other: $t) {
233 *self = *self + Saturating(other);
236 forward_ref_op_assign! { impl AddAssign, add_assign for Saturating<$t>, $t }
238 #[unstable(feature = "saturating_int_impl", issue = "87920")]
239 impl Sub for Saturating<$t> {
240 type Output = Saturating<$t>;
243 fn sub(self, other: Saturating<$t>) -> Saturating<$t> {
244 Saturating(self.0.saturating_sub(other.0))
247 forward_ref_binop! { impl Sub, sub for Saturating<$t>, Saturating<$t>,
248 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
250 #[unstable(feature = "saturating_int_impl", issue = "87920")]
251 impl SubAssign for Saturating<$t> {
253 fn sub_assign(&mut self, other: Saturating<$t>) {
254 *self = *self - other;
257 forward_ref_op_assign! { impl SubAssign, sub_assign for Saturating<$t>, Saturating<$t> }
259 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
260 impl SubAssign<$t> for Saturating<$t> {
262 fn sub_assign(&mut self, other: $t) {
263 *self = *self - Saturating(other);
266 forward_ref_op_assign! { impl SubAssign, sub_assign for Saturating<$t>, $t }
268 #[unstable(feature = "saturating_int_impl", issue = "87920")]
269 impl Mul for Saturating<$t> {
270 type Output = Saturating<$t>;
273 fn mul(self, other: Saturating<$t>) -> Saturating<$t> {
274 Saturating(self.0.saturating_mul(other.0))
277 forward_ref_binop! { impl Mul, mul for Saturating<$t>, Saturating<$t>,
278 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
280 #[unstable(feature = "saturating_int_impl", issue = "87920")]
281 impl MulAssign for Saturating<$t> {
283 fn mul_assign(&mut self, other: Saturating<$t>) {
284 *self = *self * other;
287 forward_ref_op_assign! { impl MulAssign, mul_assign for Saturating<$t>, Saturating<$t> }
289 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
290 impl MulAssign<$t> for Saturating<$t> {
292 fn mul_assign(&mut self, other: $t) {
293 *self = *self * Saturating(other);
296 forward_ref_op_assign! { impl MulAssign, mul_assign for Saturating<$t>, $t }
303 /// #![feature(saturating_int_impl)]
304 /// use std::num::Saturating;
306 #[doc = concat!("assert_eq!(Saturating(2", stringify!($t), "), Saturating(5", stringify!($t), ") / Saturating(2));")]
307 #[doc = concat!("assert_eq!(Saturating(", stringify!($t), "::MAX), Saturating(", stringify!($t), "::MAX) / Saturating(1));")]
308 #[doc = concat!("assert_eq!(Saturating(", stringify!($t), "::MIN), Saturating(", stringify!($t), "::MIN) / Saturating(1));")]
312 /// #![feature(saturating_int_impl)]
313 /// use std::num::Saturating;
315 #[doc = concat!("let _ = Saturating(0", stringify!($t), ") / Saturating(0);")]
317 #[unstable(feature = "saturating_int_impl", issue = "87920")]
318 impl Div for Saturating<$t> {
319 type Output = Saturating<$t>;
322 fn div(self, other: Saturating<$t>) -> Saturating<$t> {
323 Saturating(self.0.saturating_div(other.0))
326 forward_ref_binop! { impl Div, div for Saturating<$t>, Saturating<$t>,
327 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
330 #[unstable(feature = "saturating_int_impl", issue = "87920")]
331 impl DivAssign for Saturating<$t> {
333 fn div_assign(&mut self, other: Saturating<$t>) {
334 *self = *self / other;
337 forward_ref_op_assign! { impl DivAssign, div_assign for Saturating<$t>, Saturating<$t> }
339 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
340 impl DivAssign<$t> for Saturating<$t> {
342 fn div_assign(&mut self, other: $t) {
343 *self = *self / Saturating(other);
346 forward_ref_op_assign! { impl DivAssign, div_assign for Saturating<$t>, $t }
348 #[unstable(feature = "saturating_int_impl", issue = "87920")]
349 impl Rem for Saturating<$t> {
350 type Output = Saturating<$t>;
353 fn rem(self, other: Saturating<$t>) -> Saturating<$t> {
354 Saturating(self.0.rem(other.0))
357 forward_ref_binop! { impl Rem, rem for Saturating<$t>, Saturating<$t>,
358 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
360 #[unstable(feature = "saturating_int_impl", issue = "87920")]
361 impl RemAssign for Saturating<$t> {
363 fn rem_assign(&mut self, other: Saturating<$t>) {
364 *self = *self % other;
367 forward_ref_op_assign! { impl RemAssign, rem_assign for Saturating<$t>, Saturating<$t> }
369 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
370 impl RemAssign<$t> for Saturating<$t> {
372 fn rem_assign(&mut self, other: $t) {
373 *self = *self % Saturating(other);
376 forward_ref_op_assign! { impl RemAssign, rem_assign for Saturating<$t>, $t }
378 #[unstable(feature = "saturating_int_impl", issue = "87920")]
379 impl Not for Saturating<$t> {
380 type Output = Saturating<$t>;
383 fn not(self) -> Saturating<$t> {
387 forward_ref_unop! { impl Not, not for Saturating<$t>,
388 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
390 #[unstable(feature = "saturating_int_impl", issue = "87920")]
391 impl BitXor for Saturating<$t> {
392 type Output = Saturating<$t>;
395 fn bitxor(self, other: Saturating<$t>) -> Saturating<$t> {
396 Saturating(self.0 ^ other.0)
399 forward_ref_binop! { impl BitXor, bitxor for Saturating<$t>, Saturating<$t>,
400 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
402 #[unstable(feature = "saturating_int_impl", issue = "87920")]
403 impl BitXorAssign for Saturating<$t> {
405 fn bitxor_assign(&mut self, other: Saturating<$t>) {
406 *self = *self ^ other;
409 forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for Saturating<$t>, Saturating<$t> }
411 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
412 impl BitXorAssign<$t> for Saturating<$t> {
414 fn bitxor_assign(&mut self, other: $t) {
415 *self = *self ^ Saturating(other);
418 forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for Saturating<$t>, $t }
420 #[unstable(feature = "saturating_int_impl", issue = "87920")]
421 impl BitOr for Saturating<$t> {
422 type Output = Saturating<$t>;
425 fn bitor(self, other: Saturating<$t>) -> Saturating<$t> {
426 Saturating(self.0 | other.0)
429 forward_ref_binop! { impl BitOr, bitor for Saturating<$t>, Saturating<$t>,
430 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
432 #[unstable(feature = "saturating_int_impl", issue = "87920")]
433 impl BitOrAssign for Saturating<$t> {
435 fn bitor_assign(&mut self, other: Saturating<$t>) {
436 *self = *self | other;
439 forward_ref_op_assign! { impl BitOrAssign, bitor_assign for Saturating<$t>, Saturating<$t> }
441 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
442 impl BitOrAssign<$t> for Saturating<$t> {
444 fn bitor_assign(&mut self, other: $t) {
445 *self = *self | Saturating(other);
448 forward_ref_op_assign! { impl BitOrAssign, bitor_assign for Saturating<$t>, $t }
450 #[unstable(feature = "saturating_int_impl", issue = "87920")]
451 impl BitAnd for Saturating<$t> {
452 type Output = Saturating<$t>;
455 fn bitand(self, other: Saturating<$t>) -> Saturating<$t> {
456 Saturating(self.0 & other.0)
459 forward_ref_binop! { impl BitAnd, bitand for Saturating<$t>, Saturating<$t>,
460 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
462 #[unstable(feature = "saturating_int_impl", issue = "87920")]
463 impl BitAndAssign for Saturating<$t> {
465 fn bitand_assign(&mut self, other: Saturating<$t>) {
466 *self = *self & other;
469 forward_ref_op_assign! { impl BitAndAssign, bitand_assign for Saturating<$t>, Saturating<$t> }
471 #[unstable(feature = "saturating_int_assign_impl", issue = "92354")]
472 impl BitAndAssign<$t> for Saturating<$t> {
474 fn bitand_assign(&mut self, other: $t) {
475 *self = *self & Saturating(other);
478 forward_ref_op_assign! { impl BitAndAssign, bitand_assign for Saturating<$t>, $t }
483 saturating_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
485 macro_rules! saturating_int_impl {
487 impl Saturating<$t> {
488 /// Returns the smallest value that can be represented by this integer type.
495 /// #![feature(saturating_int_impl)]
496 /// use std::num::Saturating;
498 #[doc = concat!("assert_eq!(<Saturating<", stringify!($t), ">>::MIN, Saturating(", stringify!($t), "::MIN));")]
500 #[unstable(feature = "saturating_int_impl", issue = "87920")]
501 pub const MIN: Self = Self(<$t>::MIN);
503 /// Returns the largest value that can be represented by this integer type.
510 /// #![feature(saturating_int_impl)]
511 /// use std::num::Saturating;
513 #[doc = concat!("assert_eq!(<Saturating<", stringify!($t), ">>::MAX, Saturating(", stringify!($t), "::MAX));")]
515 #[unstable(feature = "saturating_int_impl", issue = "87920")]
516 pub const MAX: Self = Self(<$t>::MAX);
518 /// Returns the size of this integer type in bits.
525 /// #![feature(saturating_int_impl)]
526 /// use std::num::Saturating;
528 #[doc = concat!("assert_eq!(<Saturating<", stringify!($t), ">>::BITS, ", stringify!($t), "::BITS);")]
530 #[unstable(feature = "saturating_int_impl", issue = "87920")]
531 pub const BITS: u32 = <$t>::BITS;
533 /// Returns the number of ones in the binary representation of `self`.
540 /// #![feature(saturating_int_impl)]
541 /// use std::num::Saturating;
543 #[doc = concat!("let n = Saturating(0b01001100", stringify!($t), ");")]
545 /// assert_eq!(n.count_ones(), 3);
548 #[doc(alias = "popcount")]
549 #[doc(alias = "popcnt")]
550 #[must_use = "this returns the result of the operation, \
551 without modifying the original"]
552 #[unstable(feature = "saturating_int_impl", issue = "87920")]
553 pub const fn count_ones(self) -> u32 {
557 /// Returns the number of zeros in the binary representation of `self`.
564 /// #![feature(saturating_int_impl)]
565 /// use std::num::Saturating;
567 #[doc = concat!("assert_eq!(Saturating(!0", stringify!($t), ").count_zeros(), 0);")]
570 #[must_use = "this returns the result of the operation, \
571 without modifying the original"]
572 #[unstable(feature = "saturating_int_impl", issue = "87920")]
573 pub const fn count_zeros(self) -> u32 {
577 /// Returns the number of trailing zeros in the binary representation of `self`.
584 /// #![feature(saturating_int_impl)]
585 /// use std::num::Saturating;
587 #[doc = concat!("let n = Saturating(0b0101000", stringify!($t), ");")]
589 /// assert_eq!(n.trailing_zeros(), 3);
592 #[must_use = "this returns the result of the operation, \
593 without modifying the original"]
594 #[unstable(feature = "saturating_int_impl", issue = "87920")]
595 pub const fn trailing_zeros(self) -> u32 {
596 self.0.trailing_zeros()
599 /// Shifts the bits to the left by a specified amount, `n`,
600 /// saturating the truncated bits to the end of the resulting
603 /// Please note this isn't the same operation as the `<<` shifting
611 /// #![feature(saturating_int_impl)]
612 /// use std::num::Saturating;
614 /// let n: Saturating<i64> = Saturating(0x0123456789ABCDEF);
615 /// let m: Saturating<i64> = Saturating(-0x76543210FEDCBA99);
617 /// assert_eq!(n.rotate_left(32), m);
620 #[must_use = "this returns the result of the operation, \
621 without modifying the original"]
622 #[unstable(feature = "saturating_int_impl", issue = "87920")]
623 pub const fn rotate_left(self, n: u32) -> Self {
624 Saturating(self.0.rotate_left(n))
627 /// Shifts the bits to the right by a specified amount, `n`,
628 /// saturating the truncated bits to the beginning of the resulting
631 /// Please note this isn't the same operation as the `>>` shifting
639 /// #![feature(saturating_int_impl)]
640 /// use std::num::Saturating;
642 /// let n: Saturating<i64> = Saturating(0x0123456789ABCDEF);
643 /// let m: Saturating<i64> = Saturating(-0xFEDCBA987654322);
645 /// assert_eq!(n.rotate_right(4), m);
648 #[must_use = "this returns the result of the operation, \
649 without modifying the original"]
650 #[unstable(feature = "saturating_int_impl", issue = "87920")]
651 pub const fn rotate_right(self, n: u32) -> Self {
652 Saturating(self.0.rotate_right(n))
655 /// Reverses the byte order of the integer.
662 /// #![feature(saturating_int_impl)]
663 /// use std::num::Saturating;
665 /// let n: Saturating<i16> = Saturating(0b0000000_01010101);
666 /// assert_eq!(n, Saturating(85));
668 /// let m = n.swap_bytes();
670 /// assert_eq!(m, Saturating(0b01010101_00000000));
671 /// assert_eq!(m, Saturating(21760));
674 #[must_use = "this returns the result of the operation, \
675 without modifying the original"]
676 #[unstable(feature = "saturating_int_impl", issue = "87920")]
677 pub const fn swap_bytes(self) -> Self {
678 Saturating(self.0.swap_bytes())
681 /// Reverses the bit pattern of the integer.
685 /// Please note that this example is shared between integer types.
686 /// Which explains why `i16` is used here.
691 /// #![feature(saturating_int_impl)]
692 /// use std::num::Saturating;
694 /// let n = Saturating(0b0000000_01010101i16);
695 /// assert_eq!(n, Saturating(85));
697 /// let m = n.reverse_bits();
699 /// assert_eq!(m.0 as u16, 0b10101010_00000000);
700 /// assert_eq!(m, Saturating(-22016));
703 #[unstable(feature = "saturating_int_impl", issue = "87920")]
704 #[rustc_const_unstable(feature = "saturating_int_impl", issue = "87920")]
705 #[must_use = "this returns the result of the operation, \
706 without modifying the original"]
707 pub const fn reverse_bits(self) -> Self {
708 Saturating(self.0.reverse_bits())
711 /// Converts an integer from big endian to the target's endianness.
713 /// On big endian this is a no-op. On little endian the bytes are
721 /// #![feature(saturating_int_impl)]
722 /// use std::num::Saturating;
724 #[doc = concat!("let n = Saturating(0x1A", stringify!($t), ");")]
726 /// if cfg!(target_endian = "big") {
727 #[doc = concat!(" assert_eq!(<Saturating<", stringify!($t), ">>::from_be(n), n)")]
729 #[doc = concat!(" assert_eq!(<Saturating<", stringify!($t), ">>::from_be(n), n.swap_bytes())")]
734 #[unstable(feature = "saturating_int_impl", issue = "87920")]
735 pub const fn from_be(x: Self) -> Self {
736 Saturating(<$t>::from_be(x.0))
739 /// Converts an integer from little endian to the target's endianness.
741 /// On little endian this is a no-op. On big endian the bytes are
749 /// #![feature(saturating_int_impl)]
750 /// use std::num::Saturating;
752 #[doc = concat!("let n = Saturating(0x1A", stringify!($t), ");")]
754 /// if cfg!(target_endian = "little") {
755 #[doc = concat!(" assert_eq!(<Saturating<", stringify!($t), ">>::from_le(n), n)")]
757 #[doc = concat!(" assert_eq!(<Saturating<", stringify!($t), ">>::from_le(n), n.swap_bytes())")]
762 #[unstable(feature = "saturating_int_impl", issue = "87920")]
763 pub const fn from_le(x: Self) -> Self {
764 Saturating(<$t>::from_le(x.0))
767 /// Converts `self` to big endian from the target's endianness.
769 /// On big endian this is a no-op. On little endian the bytes are
777 /// #![feature(saturating_int_impl)]
778 /// use std::num::Saturating;
780 #[doc = concat!("let n = Saturating(0x1A", stringify!($t), ");")]
782 /// if cfg!(target_endian = "big") {
783 /// assert_eq!(n.to_be(), n)
785 /// assert_eq!(n.to_be(), n.swap_bytes())
789 #[unstable(feature = "saturating_int_impl", issue = "87920")]
790 #[must_use = "this returns the result of the operation, \
791 without modifying the original"]
792 pub const fn to_be(self) -> Self {
793 Saturating(self.0.to_be())
796 /// Converts `self` to little endian from the target's endianness.
798 /// On little endian this is a no-op. On big endian the bytes are
806 /// #![feature(saturating_int_impl)]
807 /// use std::num::Saturating;
809 #[doc = concat!("let n = Saturating(0x1A", stringify!($t), ");")]
811 /// if cfg!(target_endian = "little") {
812 /// assert_eq!(n.to_le(), n)
814 /// assert_eq!(n.to_le(), n.swap_bytes())
818 #[unstable(feature = "saturating_int_impl", issue = "87920")]
819 #[must_use = "this returns the result of the operation, \
820 without modifying the original"]
821 pub const fn to_le(self) -> Self {
822 Saturating(self.0.to_le())
825 /// Raises self to the power of `exp`, using exponentiation by squaring.
832 /// #![feature(saturating_int_impl)]
833 /// use std::num::Saturating;
835 #[doc = concat!("assert_eq!(Saturating(3", stringify!($t), ").pow(4), Saturating(81));")]
838 /// Results that are too large are saturated:
841 /// #![feature(saturating_int_impl)]
842 /// use std::num::Saturating;
844 /// assert_eq!(Saturating(3i8).pow(5), Saturating(127));
845 /// assert_eq!(Saturating(3i8).pow(6), Saturating(127));
848 #[unstable(feature = "saturating_int_impl", issue = "87920")]
849 #[must_use = "this returns the result of the operation, \
850 without modifying the original"]
851 pub fn pow(self, exp: u32) -> Self {
852 Saturating(self.0.saturating_pow(exp))
858 saturating_int_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
860 macro_rules! saturating_int_impl_signed {
862 impl Saturating<$t> {
863 /// Returns the number of leading zeros in the binary representation of `self`.
870 /// #![feature(saturating_int_impl)]
871 /// use std::num::Saturating;
873 #[doc = concat!("let n = Saturating(", stringify!($t), "::MAX >> 2);")]
875 /// assert_eq!(n.leading_zeros(), 3);
878 #[unstable(feature = "saturating_int_impl", issue = "87920")]
879 #[must_use = "this returns the result of the operation, \
880 without modifying the original"]
881 pub const fn leading_zeros(self) -> u32 {
882 self.0.leading_zeros()
885 /// Saturating absolute value. Computes `self.abs()`, returning `MAX` if `self == MIN`
886 /// instead of overflowing.
893 /// #![feature(saturating_int_impl)]
894 /// use std::num::Saturating;
896 #[doc = concat!("assert_eq!(Saturating(100", stringify!($t), ").abs(), Saturating(100));")]
897 #[doc = concat!("assert_eq!(Saturating(-100", stringify!($t), ").abs(), Saturating(100));")]
898 #[doc = concat!("assert_eq!(Saturating(", stringify!($t), "::MIN).abs(), Saturating((", stringify!($t), "::MIN + 1).abs()));")]
899 #[doc = concat!("assert_eq!(Saturating(", stringify!($t), "::MIN).abs(), Saturating(", stringify!($t), "::MIN.saturating_abs()));")]
900 #[doc = concat!("assert_eq!(Saturating(", stringify!($t), "::MIN).abs(), Saturating(", stringify!($t), "::MAX));")]
903 #[unstable(feature = "saturating_int_impl", issue = "87920")]
904 #[must_use = "this returns the result of the operation, \
905 without modifying the original"]
906 pub fn abs(self) -> Saturating<$t> {
907 Saturating(self.0.saturating_abs())
910 /// Returns a number representing sign of `self`.
912 /// - `0` if the number is zero
913 /// - `1` if the number is positive
914 /// - `-1` if the number is negative
921 /// #![feature(saturating_int_impl)]
922 /// use std::num::Saturating;
924 #[doc = concat!("assert_eq!(Saturating(10", stringify!($t), ").signum(), Saturating(1));")]
925 #[doc = concat!("assert_eq!(Saturating(0", stringify!($t), ").signum(), Saturating(0));")]
926 #[doc = concat!("assert_eq!(Saturating(-10", stringify!($t), ").signum(), Saturating(-1));")]
929 #[unstable(feature = "saturating_int_impl", issue = "87920")]
930 #[must_use = "this returns the result of the operation, \
931 without modifying the original"]
932 pub fn signum(self) -> Saturating<$t> {
933 Saturating(self.0.signum())
936 /// Returns `true` if `self` is positive and `false` if the number is zero or
944 /// #![feature(saturating_int_impl)]
945 /// use std::num::Saturating;
947 #[doc = concat!("assert!(Saturating(10", stringify!($t), ").is_positive());")]
948 #[doc = concat!("assert!(!Saturating(-10", stringify!($t), ").is_positive());")]
952 #[unstable(feature = "saturating_int_impl", issue = "87920")]
953 pub const fn is_positive(self) -> bool {
957 /// Returns `true` if `self` is negative and `false` if the number is zero or
965 /// #![feature(saturating_int_impl)]
966 /// use std::num::Saturating;
968 #[doc = concat!("assert!(Saturating(-10", stringify!($t), ").is_negative());")]
969 #[doc = concat!("assert!(!Saturating(10", stringify!($t), ").is_negative());")]
973 #[unstable(feature = "saturating_int_impl", issue = "87920")]
974 pub const fn is_negative(self) -> bool {
979 #[unstable(feature = "saturating_int_impl", issue = "87920")]
980 impl Neg for Saturating<$t> {
983 fn neg(self) -> Self {
984 Saturating(self.0.saturating_neg())
987 forward_ref_unop! { impl Neg, neg for Saturating<$t>,
988 #[unstable(feature = "saturating_int_impl", issue = "87920")] }
992 saturating_int_impl_signed! { isize i8 i16 i32 i64 i128 }
994 macro_rules! saturating_int_impl_unsigned {
996 impl Saturating<$t> {
997 /// Returns the number of leading zeros in the binary representation of `self`.
1004 /// #![feature(saturating_int_impl)]
1005 /// use std::num::Saturating;
1007 #[doc = concat!("let n = Saturating(", stringify!($t), "::MAX >> 2);")]
1009 /// assert_eq!(n.leading_zeros(), 2);
1012 #[unstable(feature = "saturating_int_impl", issue = "87920")]
1013 #[must_use = "this returns the result of the operation, \
1014 without modifying the original"]
1015 pub const fn leading_zeros(self) -> u32 {
1016 self.0.leading_zeros()
1019 /// Returns `true` if and only if `self == 2^k` for some `k`.
1026 /// #![feature(saturating_int_impl)]
1027 /// use std::num::Saturating;
1029 #[doc = concat!("assert!(Saturating(16", stringify!($t), ").is_power_of_two());")]
1030 #[doc = concat!("assert!(!Saturating(10", stringify!($t), ").is_power_of_two());")]
1034 #[unstable(feature = "saturating_int_impl", issue = "87920")]
1035 pub fn is_power_of_two(self) -> bool {
1036 self.0.is_power_of_two()
1043 saturating_int_impl_unsigned! { usize u8 u16 u32 u64 u128 }
1045 // Related to potential Shl and ShlAssign implementation
1048 // #![allow(non_upper_case_globals)]
1050 // #[cfg(target_pointer_width = "16")]
1052 // pub const usize: u32 = super::u16;
1053 // pub const isize: u32 = super::i16;
1056 // #[cfg(target_pointer_width = "32")]
1058 // pub const usize: u32 = super::u32;
1059 // pub const isize: u32 = super::i32;
1062 // #[cfg(target_pointer_width = "64")]
1064 // pub const usize: u32 = super::u64;
1065 // pub const isize: u32 = super::i64;
1068 // pub const i8: u32 = (1 << 3) - 1;
1069 // pub const i16: u32 = (1 << 4) - 1;
1070 // pub const i32: u32 = (1 << 5) - 1;
1071 // pub const i64: u32 = (1 << 6) - 1;
1072 // pub const i128: u32 = (1 << 7) - 1;
1073 // pub use self::platform::isize;
1075 // pub const u8: u32 = i8;
1076 // pub const u16: u32 = i16;
1077 // pub const u32: u32 = i32;
1078 // pub const u64: u32 = i64;
1079 // pub const u128: u32 = i128;
1080 // pub use self::platform::usize;