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Diffstat (limited to 'vendor/rand/src/rand_impls.rs')
-rw-r--r-- | vendor/rand/src/rand_impls.rs | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/vendor/rand/src/rand_impls.rs b/vendor/rand/src/rand_impls.rs deleted file mode 100644 index a865bb6..0000000 --- a/vendor/rand/src/rand_impls.rs +++ /dev/null @@ -1,299 +0,0 @@ -// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -//! The implementations of `Rand` for the built-in types. - -use core::{char, mem}; - -use {Rand,Rng}; - -impl Rand for isize { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> isize { - if mem::size_of::<isize>() == 4 { - rng.gen::<i32>() as isize - } else { - rng.gen::<i64>() as isize - } - } -} - -impl Rand for i8 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> i8 { - rng.next_u32() as i8 - } -} - -impl Rand for i16 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> i16 { - rng.next_u32() as i16 - } -} - -impl Rand for i32 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> i32 { - rng.next_u32() as i32 - } -} - -impl Rand for i64 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> i64 { - rng.next_u64() as i64 - } -} - -#[cfg(feature = "i128_support")] -impl Rand for i128 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> i128 { - rng.gen::<u128>() as i128 - } -} - -impl Rand for usize { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> usize { - if mem::size_of::<usize>() == 4 { - rng.gen::<u32>() as usize - } else { - rng.gen::<u64>() as usize - } - } -} - -impl Rand for u8 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> u8 { - rng.next_u32() as u8 - } -} - -impl Rand for u16 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> u16 { - rng.next_u32() as u16 - } -} - -impl Rand for u32 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> u32 { - rng.next_u32() - } -} - -impl Rand for u64 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> u64 { - rng.next_u64() - } -} - -#[cfg(feature = "i128_support")] -impl Rand for u128 { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> u128 { - ((rng.next_u64() as u128) << 64) | (rng.next_u64() as u128) - } -} - - -macro_rules! float_impls { - ($mod_name:ident, $ty:ty, $mantissa_bits:expr, $method_name:ident) => { - mod $mod_name { - use {Rand, Rng, Open01, Closed01}; - - const SCALE: $ty = (1u64 << $mantissa_bits) as $ty; - - impl Rand for $ty { - /// Generate a floating point number in the half-open - /// interval `[0,1)`. - /// - /// See `Closed01` for the closed interval `[0,1]`, - /// and `Open01` for the open interval `(0,1)`. - #[inline] - fn rand<R: Rng>(rng: &mut R) -> $ty { - rng.$method_name() - } - } - impl Rand for Open01<$ty> { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> Open01<$ty> { - // add a small amount (specifically 2 bits below - // the precision of f64/f32 at 1.0), so that small - // numbers are larger than 0, but large numbers - // aren't pushed to/above 1. - Open01(rng.$method_name() + 0.25 / SCALE) - } - } - impl Rand for Closed01<$ty> { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> Closed01<$ty> { - // rescale so that 1.0 - epsilon becomes 1.0 - // precisely. - Closed01(rng.$method_name() * SCALE / (SCALE - 1.0)) - } - } - } - } -} -float_impls! { f64_rand_impls, f64, 53, next_f64 } -float_impls! { f32_rand_impls, f32, 24, next_f32 } - -impl Rand for char { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> char { - // a char is 21 bits - const CHAR_MASK: u32 = 0x001f_ffff; - loop { - // Rejection sampling. About 0.2% of numbers with at most - // 21-bits are invalid codepoints (surrogates), so this - // will succeed first go almost every time. - match char::from_u32(rng.next_u32() & CHAR_MASK) { - Some(c) => return c, - None => {} - } - } - } -} - -impl Rand for bool { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> bool { - rng.gen::<u8>() & 1 == 1 - } -} - -macro_rules! tuple_impl { - // use variables to indicate the arity of the tuple - ($($tyvar:ident),* ) => { - // the trailing commas are for the 1 tuple - impl< - $( $tyvar : Rand ),* - > Rand for ( $( $tyvar ),* , ) { - - #[inline] - fn rand<R: Rng>(_rng: &mut R) -> ( $( $tyvar ),* , ) { - ( - // use the $tyvar's to get the appropriate number of - // repeats (they're not actually needed) - $( - _rng.gen::<$tyvar>() - ),* - , - ) - } - } - } -} - -impl Rand for () { - #[inline] - fn rand<R: Rng>(_: &mut R) -> () { () } -} -tuple_impl!{A} -tuple_impl!{A, B} -tuple_impl!{A, B, C} -tuple_impl!{A, B, C, D} -tuple_impl!{A, B, C, D, E} -tuple_impl!{A, B, C, D, E, F} -tuple_impl!{A, B, C, D, E, F, G} -tuple_impl!{A, B, C, D, E, F, G, H} -tuple_impl!{A, B, C, D, E, F, G, H, I} -tuple_impl!{A, B, C, D, E, F, G, H, I, J} -tuple_impl!{A, B, C, D, E, F, G, H, I, J, K} -tuple_impl!{A, B, C, D, E, F, G, H, I, J, K, L} - -macro_rules! array_impl { - {$n:expr, $t:ident, $($ts:ident,)*} => { - array_impl!{($n - 1), $($ts,)*} - - impl<T> Rand for [T; $n] where T: Rand { - #[inline] - fn rand<R: Rng>(_rng: &mut R) -> [T; $n] { - [_rng.gen::<$t>(), $(_rng.gen::<$ts>()),*] - } - } - }; - {$n:expr,} => { - impl<T> Rand for [T; $n] { - fn rand<R: Rng>(_rng: &mut R) -> [T; $n] { [] } - } - }; -} - -array_impl!{32, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,} - -impl<T:Rand> Rand for Option<T> { - #[inline] - fn rand<R: Rng>(rng: &mut R) -> Option<T> { - if rng.gen() { - Some(rng.gen()) - } else { - None - } - } -} - -#[cfg(test)] -mod tests { - use {Rng, thread_rng, Open01, Closed01}; - - struct ConstantRng(u64); - impl Rng for ConstantRng { - fn next_u32(&mut self) -> u32 { - let ConstantRng(v) = *self; - v as u32 - } - fn next_u64(&mut self) -> u64 { - let ConstantRng(v) = *self; - v - } - } - - #[test] - fn floating_point_edge_cases() { - // the test for exact equality is correct here. - assert!(ConstantRng(0xffff_ffff).gen::<f32>() != 1.0); - assert!(ConstantRng(0xffff_ffff_ffff_ffff).gen::<f64>() != 1.0); - } - - #[test] - fn rand_open() { - // this is unlikely to catch an incorrect implementation that - // generates exactly 0 or 1, but it keeps it sane. - let mut rng = thread_rng(); - for _ in 0..1_000 { - // strict inequalities - let Open01(f) = rng.gen::<Open01<f64>>(); - assert!(0.0 < f && f < 1.0); - - let Open01(f) = rng.gen::<Open01<f32>>(); - assert!(0.0 < f && f < 1.0); - } - } - - #[test] - fn rand_closed() { - let mut rng = thread_rng(); - for _ in 0..1_000 { - // strict inequalities - let Closed01(f) = rng.gen::<Closed01<f64>>(); - assert!(0.0 <= f && f <= 1.0); - - let Closed01(f) = rng.gen::<Closed01<f32>>(); - assert!(0.0 <= f && f <= 1.0); - } - } -} |