rust/src/libstd/num/mod.rs
2014-11-16 12:41:55 +11:00

786 lines
30 KiB
Rust

// Copyright 2012-2014 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.
//! Numeric traits and functions for generic mathematics
//!
//! These are implemented for the primitive numeric types in `std::{u8, u16,
//! u32, u64, uint, i8, i16, i32, i64, int, f32, f64}`.
#![experimental]
#![allow(missing_docs)]
#[cfg(test)] use cmp::PartialEq;
#[cfg(test)] use fmt::Show;
#[cfg(test)] use ops::{Add, Sub, Mul, Div, Rem};
pub use core::num::{Num, div_rem, Zero, zero, One, one};
pub use core::num::{Unsigned, pow, Bounded};
pub use core::num::{Primitive, Int, SignedInt, UnsignedInt};
pub use core::num::{cast, FromPrimitive, NumCast, ToPrimitive};
pub use core::num::{next_power_of_two, is_power_of_two};
pub use core::num::{checked_next_power_of_two};
pub use core::num::{from_int, from_i8, from_i16, from_i32, from_i64};
pub use core::num::{from_uint, from_u8, from_u16, from_u32, from_u64};
pub use core::num::{from_f32, from_f64};
pub use core::num::{FromStrRadix, from_str_radix};
pub use core::num::{FPCategory, FPNaN, FPInfinite, FPZero, FPSubnormal};
pub use core::num::{FPNormal, Float};
pub mod strconv;
/// Mathematical operations on primitive floating point numbers.
pub trait FloatMath: Float {
/// Constructs a floating point number created by multiplying `x` by 2
/// raised to the power of `exp`.
fn ldexp(x: Self, exp: int) -> Self;
/// Breaks the number into a normalized fraction and a base-2 exponent,
/// satisfying:
///
/// * `self = x * pow(2, exp)`
///
/// * `0.5 <= abs(x) < 1.0`
fn frexp(self) -> (Self, int);
/// Returns the next representable floating-point value in the direction of
/// `other`.
fn next_after(self, other: Self) -> Self;
/// Returns the maximum of the two numbers.
fn max(self, other: Self) -> Self;
/// Returns the minimum of the two numbers.
fn min(self, other: Self) -> Self;
/// The positive difference of two numbers. Returns `0.0` if the number is
/// less than or equal to `other`, otherwise the difference between`self`
/// and `other` is returned.
fn abs_sub(self, other: Self) -> Self;
/// Take the cubic root of a number.
fn cbrt(self) -> Self;
/// Calculate the length of the hypotenuse of a right-angle triangle given
/// legs of length `x` and `y`.
fn hypot(self, other: Self) -> Self;
/// Computes the sine of a number (in radians).
fn sin(self) -> Self;
/// Computes the cosine of a number (in radians).
fn cos(self) -> Self;
/// Computes the tangent of a number (in radians).
fn tan(self) -> Self;
/// Computes the arcsine of a number. Return value is in radians in
/// the range [-pi/2, pi/2] or NaN if the number is outside the range
/// [-1, 1].
fn asin(self) -> Self;
/// Computes the arccosine of a number. Return value is in radians in
/// the range [0, pi] or NaN if the number is outside the range
/// [-1, 1].
fn acos(self) -> Self;
/// Computes the arctangent of a number. Return value is in radians in the
/// range [-pi/2, pi/2];
fn atan(self) -> Self;
/// Computes the four quadrant arctangent of a number, `y`, and another
/// number `x`. Return value is in radians in the range [-pi, pi].
fn atan2(self, other: Self) -> Self;
/// Simultaneously computes the sine and cosine of the number, `x`. Returns
/// `(sin(x), cos(x))`.
fn sin_cos(self) -> (Self, Self);
/// Returns the exponential of the number, minus 1, in a way that is
/// accurate even if the number is close to zero.
fn exp_m1(self) -> Self;
/// Returns the natural logarithm of the number plus 1 (`ln(1+n)`) more
/// accurately than if the operations were performed separately.
fn ln_1p(self) -> Self;
/// Hyperbolic sine function.
fn sinh(self) -> Self;
/// Hyperbolic cosine function.
fn cosh(self) -> Self;
/// Hyperbolic tangent function.
fn tanh(self) -> Self;
/// Inverse hyperbolic sine function.
fn asinh(self) -> Self;
/// Inverse hyperbolic cosine function.
fn acosh(self) -> Self;
/// Inverse hyperbolic tangent function.
fn atanh(self) -> Self;
}
// DEPRECATED
#[deprecated = "Use `FloatMath::abs_sub`"]
pub fn abs_sub<T: FloatMath>(x: T, y: T) -> T {
x.abs_sub(y)
}
/// Helper function for testing numeric operations
#[cfg(test)]
pub fn test_num<T>(ten: T, two: T) where
T: PartialEq + NumCast
+ Add<T, T> + Sub<T, T>
+ Mul<T, T> + Div<T, T>
+ Rem<T, T> + Show
{
assert_eq!(ten.add(&two), cast(12i).unwrap());
assert_eq!(ten.sub(&two), cast(8i).unwrap());
assert_eq!(ten.mul(&two), cast(20i).unwrap());
assert_eq!(ten.div(&two), cast(5i).unwrap());
assert_eq!(ten.rem(&two), cast(0i).unwrap());
assert_eq!(ten.add(&two), ten + two);
assert_eq!(ten.sub(&two), ten - two);
assert_eq!(ten.mul(&two), ten * two);
assert_eq!(ten.div(&two), ten / two);
assert_eq!(ten.rem(&two), ten % two);
}
#[cfg(test)]
mod tests {
use prelude::*;
use super::*;
use i8;
use i16;
use i32;
use i64;
use int;
use u8;
use u16;
use u32;
use u64;
use uint;
macro_rules! test_cast_20(
($_20:expr) => ({
let _20 = $_20;
assert_eq!(20u, _20.to_uint().unwrap());
assert_eq!(20u8, _20.to_u8().unwrap());
assert_eq!(20u16, _20.to_u16().unwrap());
assert_eq!(20u32, _20.to_u32().unwrap());
assert_eq!(20u64, _20.to_u64().unwrap());
assert_eq!(20i, _20.to_int().unwrap());
assert_eq!(20i8, _20.to_i8().unwrap());
assert_eq!(20i16, _20.to_i16().unwrap());
assert_eq!(20i32, _20.to_i32().unwrap());
assert_eq!(20i64, _20.to_i64().unwrap());
assert_eq!(20f32, _20.to_f32().unwrap());
assert_eq!(20f64, _20.to_f64().unwrap());
assert_eq!(_20, NumCast::from(20u).unwrap());
assert_eq!(_20, NumCast::from(20u8).unwrap());
assert_eq!(_20, NumCast::from(20u16).unwrap());
assert_eq!(_20, NumCast::from(20u32).unwrap());
assert_eq!(_20, NumCast::from(20u64).unwrap());
assert_eq!(_20, NumCast::from(20i).unwrap());
assert_eq!(_20, NumCast::from(20i8).unwrap());
assert_eq!(_20, NumCast::from(20i16).unwrap());
assert_eq!(_20, NumCast::from(20i32).unwrap());
assert_eq!(_20, NumCast::from(20i64).unwrap());
assert_eq!(_20, NumCast::from(20f32).unwrap());
assert_eq!(_20, NumCast::from(20f64).unwrap());
assert_eq!(_20, cast(20u).unwrap());
assert_eq!(_20, cast(20u8).unwrap());
assert_eq!(_20, cast(20u16).unwrap());
assert_eq!(_20, cast(20u32).unwrap());
assert_eq!(_20, cast(20u64).unwrap());
assert_eq!(_20, cast(20i).unwrap());
assert_eq!(_20, cast(20i8).unwrap());
assert_eq!(_20, cast(20i16).unwrap());
assert_eq!(_20, cast(20i32).unwrap());
assert_eq!(_20, cast(20i64).unwrap());
assert_eq!(_20, cast(20f32).unwrap());
assert_eq!(_20, cast(20f64).unwrap());
})
)
#[test] fn test_u8_cast() { test_cast_20!(20u8) }
#[test] fn test_u16_cast() { test_cast_20!(20u16) }
#[test] fn test_u32_cast() { test_cast_20!(20u32) }
#[test] fn test_u64_cast() { test_cast_20!(20u64) }
#[test] fn test_uint_cast() { test_cast_20!(20u) }
#[test] fn test_i8_cast() { test_cast_20!(20i8) }
#[test] fn test_i16_cast() { test_cast_20!(20i16) }
#[test] fn test_i32_cast() { test_cast_20!(20i32) }
#[test] fn test_i64_cast() { test_cast_20!(20i64) }
#[test] fn test_int_cast() { test_cast_20!(20i) }
#[test] fn test_f32_cast() { test_cast_20!(20f32) }
#[test] fn test_f64_cast() { test_cast_20!(20f64) }
#[test]
fn test_cast_range_int_min() {
assert_eq!(int::MIN.to_int(), Some(int::MIN as int));
assert_eq!(int::MIN.to_i8(), None);
assert_eq!(int::MIN.to_i16(), None);
// int::MIN.to_i32() is word-size specific
assert_eq!(int::MIN.to_i64(), Some(int::MIN as i64));
assert_eq!(int::MIN.to_uint(), None);
assert_eq!(int::MIN.to_u8(), None);
assert_eq!(int::MIN.to_u16(), None);
assert_eq!(int::MIN.to_u32(), None);
assert_eq!(int::MIN.to_u64(), None);
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(int::MIN.to_i32(), Some(int::MIN as i32));
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(int::MIN.to_i32(), None);
}
check_word_size();
}
#[test]
fn test_cast_range_i8_min() {
assert_eq!(i8::MIN.to_int(), Some(i8::MIN as int));
assert_eq!(i8::MIN.to_i8(), Some(i8::MIN as i8));
assert_eq!(i8::MIN.to_i16(), Some(i8::MIN as i16));
assert_eq!(i8::MIN.to_i32(), Some(i8::MIN as i32));
assert_eq!(i8::MIN.to_i64(), Some(i8::MIN as i64));
assert_eq!(i8::MIN.to_uint(), None);
assert_eq!(i8::MIN.to_u8(), None);
assert_eq!(i8::MIN.to_u16(), None);
assert_eq!(i8::MIN.to_u32(), None);
assert_eq!(i8::MIN.to_u64(), None);
}
#[test]
fn test_cast_range_i16_min() {
assert_eq!(i16::MIN.to_int(), Some(i16::MIN as int));
assert_eq!(i16::MIN.to_i8(), None);
assert_eq!(i16::MIN.to_i16(), Some(i16::MIN as i16));
assert_eq!(i16::MIN.to_i32(), Some(i16::MIN as i32));
assert_eq!(i16::MIN.to_i64(), Some(i16::MIN as i64));
assert_eq!(i16::MIN.to_uint(), None);
assert_eq!(i16::MIN.to_u8(), None);
assert_eq!(i16::MIN.to_u16(), None);
assert_eq!(i16::MIN.to_u32(), None);
assert_eq!(i16::MIN.to_u64(), None);
}
#[test]
fn test_cast_range_i32_min() {
assert_eq!(i32::MIN.to_int(), Some(i32::MIN as int));
assert_eq!(i32::MIN.to_i8(), None);
assert_eq!(i32::MIN.to_i16(), None);
assert_eq!(i32::MIN.to_i32(), Some(i32::MIN as i32));
assert_eq!(i32::MIN.to_i64(), Some(i32::MIN as i64));
assert_eq!(i32::MIN.to_uint(), None);
assert_eq!(i32::MIN.to_u8(), None);
assert_eq!(i32::MIN.to_u16(), None);
assert_eq!(i32::MIN.to_u32(), None);
assert_eq!(i32::MIN.to_u64(), None);
}
#[test]
fn test_cast_range_i64_min() {
// i64::MIN.to_int() is word-size specific
assert_eq!(i64::MIN.to_i8(), None);
assert_eq!(i64::MIN.to_i16(), None);
assert_eq!(i64::MIN.to_i32(), None);
assert_eq!(i64::MIN.to_i64(), Some(i64::MIN as i64));
assert_eq!(i64::MIN.to_uint(), None);
assert_eq!(i64::MIN.to_u8(), None);
assert_eq!(i64::MIN.to_u16(), None);
assert_eq!(i64::MIN.to_u32(), None);
assert_eq!(i64::MIN.to_u64(), None);
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(i64::MIN.to_int(), None);
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(i64::MIN.to_int(), Some(i64::MIN as int));
}
check_word_size();
}
#[test]
fn test_cast_range_int_max() {
assert_eq!(int::MAX.to_int(), Some(int::MAX as int));
assert_eq!(int::MAX.to_i8(), None);
assert_eq!(int::MAX.to_i16(), None);
// int::MAX.to_i32() is word-size specific
assert_eq!(int::MAX.to_i64(), Some(int::MAX as i64));
assert_eq!(int::MAX.to_u8(), None);
assert_eq!(int::MAX.to_u16(), None);
// int::MAX.to_u32() is word-size specific
assert_eq!(int::MAX.to_u64(), Some(int::MAX as u64));
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(int::MAX.to_i32(), Some(int::MAX as i32));
assert_eq!(int::MAX.to_u32(), Some(int::MAX as u32));
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(int::MAX.to_i32(), None);
assert_eq!(int::MAX.to_u32(), None);
}
check_word_size();
}
#[test]
fn test_cast_range_i8_max() {
assert_eq!(i8::MAX.to_int(), Some(i8::MAX as int));
assert_eq!(i8::MAX.to_i8(), Some(i8::MAX as i8));
assert_eq!(i8::MAX.to_i16(), Some(i8::MAX as i16));
assert_eq!(i8::MAX.to_i32(), Some(i8::MAX as i32));
assert_eq!(i8::MAX.to_i64(), Some(i8::MAX as i64));
assert_eq!(i8::MAX.to_uint(), Some(i8::MAX as uint));
assert_eq!(i8::MAX.to_u8(), Some(i8::MAX as u8));
assert_eq!(i8::MAX.to_u16(), Some(i8::MAX as u16));
assert_eq!(i8::MAX.to_u32(), Some(i8::MAX as u32));
assert_eq!(i8::MAX.to_u64(), Some(i8::MAX as u64));
}
#[test]
fn test_cast_range_i16_max() {
assert_eq!(i16::MAX.to_int(), Some(i16::MAX as int));
assert_eq!(i16::MAX.to_i8(), None);
assert_eq!(i16::MAX.to_i16(), Some(i16::MAX as i16));
assert_eq!(i16::MAX.to_i32(), Some(i16::MAX as i32));
assert_eq!(i16::MAX.to_i64(), Some(i16::MAX as i64));
assert_eq!(i16::MAX.to_uint(), Some(i16::MAX as uint));
assert_eq!(i16::MAX.to_u8(), None);
assert_eq!(i16::MAX.to_u16(), Some(i16::MAX as u16));
assert_eq!(i16::MAX.to_u32(), Some(i16::MAX as u32));
assert_eq!(i16::MAX.to_u64(), Some(i16::MAX as u64));
}
#[test]
fn test_cast_range_i32_max() {
assert_eq!(i32::MAX.to_int(), Some(i32::MAX as int));
assert_eq!(i32::MAX.to_i8(), None);
assert_eq!(i32::MAX.to_i16(), None);
assert_eq!(i32::MAX.to_i32(), Some(i32::MAX as i32));
assert_eq!(i32::MAX.to_i64(), Some(i32::MAX as i64));
assert_eq!(i32::MAX.to_uint(), Some(i32::MAX as uint));
assert_eq!(i32::MAX.to_u8(), None);
assert_eq!(i32::MAX.to_u16(), None);
assert_eq!(i32::MAX.to_u32(), Some(i32::MAX as u32));
assert_eq!(i32::MAX.to_u64(), Some(i32::MAX as u64));
}
#[test]
fn test_cast_range_i64_max() {
// i64::MAX.to_int() is word-size specific
assert_eq!(i64::MAX.to_i8(), None);
assert_eq!(i64::MAX.to_i16(), None);
assert_eq!(i64::MAX.to_i32(), None);
assert_eq!(i64::MAX.to_i64(), Some(i64::MAX as i64));
// i64::MAX.to_uint() is word-size specific
assert_eq!(i64::MAX.to_u8(), None);
assert_eq!(i64::MAX.to_u16(), None);
assert_eq!(i64::MAX.to_u32(), None);
assert_eq!(i64::MAX.to_u64(), Some(i64::MAX as u64));
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(i64::MAX.to_int(), None);
assert_eq!(i64::MAX.to_uint(), None);
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(i64::MAX.to_int(), Some(i64::MAX as int));
assert_eq!(i64::MAX.to_uint(), Some(i64::MAX as uint));
}
check_word_size();
}
#[test]
fn test_cast_range_uint_min() {
assert_eq!(uint::MIN.to_int(), Some(uint::MIN as int));
assert_eq!(uint::MIN.to_i8(), Some(uint::MIN as i8));
assert_eq!(uint::MIN.to_i16(), Some(uint::MIN as i16));
assert_eq!(uint::MIN.to_i32(), Some(uint::MIN as i32));
assert_eq!(uint::MIN.to_i64(), Some(uint::MIN as i64));
assert_eq!(uint::MIN.to_uint(), Some(uint::MIN as uint));
assert_eq!(uint::MIN.to_u8(), Some(uint::MIN as u8));
assert_eq!(uint::MIN.to_u16(), Some(uint::MIN as u16));
assert_eq!(uint::MIN.to_u32(), Some(uint::MIN as u32));
assert_eq!(uint::MIN.to_u64(), Some(uint::MIN as u64));
}
#[test]
fn test_cast_range_u8_min() {
assert_eq!(u8::MIN.to_int(), Some(u8::MIN as int));
assert_eq!(u8::MIN.to_i8(), Some(u8::MIN as i8));
assert_eq!(u8::MIN.to_i16(), Some(u8::MIN as i16));
assert_eq!(u8::MIN.to_i32(), Some(u8::MIN as i32));
assert_eq!(u8::MIN.to_i64(), Some(u8::MIN as i64));
assert_eq!(u8::MIN.to_uint(), Some(u8::MIN as uint));
assert_eq!(u8::MIN.to_u8(), Some(u8::MIN as u8));
assert_eq!(u8::MIN.to_u16(), Some(u8::MIN as u16));
assert_eq!(u8::MIN.to_u32(), Some(u8::MIN as u32));
assert_eq!(u8::MIN.to_u64(), Some(u8::MIN as u64));
}
#[test]
fn test_cast_range_u16_min() {
assert_eq!(u16::MIN.to_int(), Some(u16::MIN as int));
assert_eq!(u16::MIN.to_i8(), Some(u16::MIN as i8));
assert_eq!(u16::MIN.to_i16(), Some(u16::MIN as i16));
assert_eq!(u16::MIN.to_i32(), Some(u16::MIN as i32));
assert_eq!(u16::MIN.to_i64(), Some(u16::MIN as i64));
assert_eq!(u16::MIN.to_uint(), Some(u16::MIN as uint));
assert_eq!(u16::MIN.to_u8(), Some(u16::MIN as u8));
assert_eq!(u16::MIN.to_u16(), Some(u16::MIN as u16));
assert_eq!(u16::MIN.to_u32(), Some(u16::MIN as u32));
assert_eq!(u16::MIN.to_u64(), Some(u16::MIN as u64));
}
#[test]
fn test_cast_range_u32_min() {
assert_eq!(u32::MIN.to_int(), Some(u32::MIN as int));
assert_eq!(u32::MIN.to_i8(), Some(u32::MIN as i8));
assert_eq!(u32::MIN.to_i16(), Some(u32::MIN as i16));
assert_eq!(u32::MIN.to_i32(), Some(u32::MIN as i32));
assert_eq!(u32::MIN.to_i64(), Some(u32::MIN as i64));
assert_eq!(u32::MIN.to_uint(), Some(u32::MIN as uint));
assert_eq!(u32::MIN.to_u8(), Some(u32::MIN as u8));
assert_eq!(u32::MIN.to_u16(), Some(u32::MIN as u16));
assert_eq!(u32::MIN.to_u32(), Some(u32::MIN as u32));
assert_eq!(u32::MIN.to_u64(), Some(u32::MIN as u64));
}
#[test]
fn test_cast_range_u64_min() {
assert_eq!(u64::MIN.to_int(), Some(u64::MIN as int));
assert_eq!(u64::MIN.to_i8(), Some(u64::MIN as i8));
assert_eq!(u64::MIN.to_i16(), Some(u64::MIN as i16));
assert_eq!(u64::MIN.to_i32(), Some(u64::MIN as i32));
assert_eq!(u64::MIN.to_i64(), Some(u64::MIN as i64));
assert_eq!(u64::MIN.to_uint(), Some(u64::MIN as uint));
assert_eq!(u64::MIN.to_u8(), Some(u64::MIN as u8));
assert_eq!(u64::MIN.to_u16(), Some(u64::MIN as u16));
assert_eq!(u64::MIN.to_u32(), Some(u64::MIN as u32));
assert_eq!(u64::MIN.to_u64(), Some(u64::MIN as u64));
}
#[test]
fn test_cast_range_uint_max() {
assert_eq!(uint::MAX.to_int(), None);
assert_eq!(uint::MAX.to_i8(), None);
assert_eq!(uint::MAX.to_i16(), None);
assert_eq!(uint::MAX.to_i32(), None);
// uint::MAX.to_i64() is word-size specific
assert_eq!(uint::MAX.to_u8(), None);
assert_eq!(uint::MAX.to_u16(), None);
// uint::MAX.to_u32() is word-size specific
assert_eq!(uint::MAX.to_u64(), Some(uint::MAX as u64));
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(uint::MAX.to_u32(), Some(uint::MAX as u32));
assert_eq!(uint::MAX.to_i64(), Some(uint::MAX as i64));
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(uint::MAX.to_u32(), None);
assert_eq!(uint::MAX.to_i64(), None);
}
check_word_size();
}
#[test]
fn test_cast_range_u8_max() {
assert_eq!(u8::MAX.to_int(), Some(u8::MAX as int));
assert_eq!(u8::MAX.to_i8(), None);
assert_eq!(u8::MAX.to_i16(), Some(u8::MAX as i16));
assert_eq!(u8::MAX.to_i32(), Some(u8::MAX as i32));
assert_eq!(u8::MAX.to_i64(), Some(u8::MAX as i64));
assert_eq!(u8::MAX.to_uint(), Some(u8::MAX as uint));
assert_eq!(u8::MAX.to_u8(), Some(u8::MAX as u8));
assert_eq!(u8::MAX.to_u16(), Some(u8::MAX as u16));
assert_eq!(u8::MAX.to_u32(), Some(u8::MAX as u32));
assert_eq!(u8::MAX.to_u64(), Some(u8::MAX as u64));
}
#[test]
fn test_cast_range_u16_max() {
assert_eq!(u16::MAX.to_int(), Some(u16::MAX as int));
assert_eq!(u16::MAX.to_i8(), None);
assert_eq!(u16::MAX.to_i16(), None);
assert_eq!(u16::MAX.to_i32(), Some(u16::MAX as i32));
assert_eq!(u16::MAX.to_i64(), Some(u16::MAX as i64));
assert_eq!(u16::MAX.to_uint(), Some(u16::MAX as uint));
assert_eq!(u16::MAX.to_u8(), None);
assert_eq!(u16::MAX.to_u16(), Some(u16::MAX as u16));
assert_eq!(u16::MAX.to_u32(), Some(u16::MAX as u32));
assert_eq!(u16::MAX.to_u64(), Some(u16::MAX as u64));
}
#[test]
fn test_cast_range_u32_max() {
// u32::MAX.to_int() is word-size specific
assert_eq!(u32::MAX.to_i8(), None);
assert_eq!(u32::MAX.to_i16(), None);
assert_eq!(u32::MAX.to_i32(), None);
assert_eq!(u32::MAX.to_i64(), Some(u32::MAX as i64));
assert_eq!(u32::MAX.to_uint(), Some(u32::MAX as uint));
assert_eq!(u32::MAX.to_u8(), None);
assert_eq!(u32::MAX.to_u16(), None);
assert_eq!(u32::MAX.to_u32(), Some(u32::MAX as u32));
assert_eq!(u32::MAX.to_u64(), Some(u32::MAX as u64));
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(u32::MAX.to_int(), None);
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(u32::MAX.to_int(), Some(u32::MAX as int));
}
check_word_size();
}
#[test]
fn test_cast_range_u64_max() {
assert_eq!(u64::MAX.to_int(), None);
assert_eq!(u64::MAX.to_i8(), None);
assert_eq!(u64::MAX.to_i16(), None);
assert_eq!(u64::MAX.to_i32(), None);
assert_eq!(u64::MAX.to_i64(), None);
// u64::MAX.to_uint() is word-size specific
assert_eq!(u64::MAX.to_u8(), None);
assert_eq!(u64::MAX.to_u16(), None);
assert_eq!(u64::MAX.to_u32(), None);
assert_eq!(u64::MAX.to_u64(), Some(u64::MAX as u64));
#[cfg(target_word_size = "32")]
fn check_word_size() {
assert_eq!(u64::MAX.to_uint(), None);
}
#[cfg(target_word_size = "64")]
fn check_word_size() {
assert_eq!(u64::MAX.to_uint(), Some(u64::MAX as uint));
}
check_word_size();
}
#[test]
fn test_saturating_add_uint() {
use uint::MAX;
assert_eq!(3u.saturating_add(5u), 8u);
assert_eq!(3u.saturating_add(MAX-1), MAX);
assert_eq!(MAX.saturating_add(MAX), MAX);
assert_eq!((MAX-2).saturating_add(1), MAX-1);
}
#[test]
fn test_saturating_sub_uint() {
use uint::MAX;
assert_eq!(5u.saturating_sub(3u), 2u);
assert_eq!(3u.saturating_sub(5u), 0u);
assert_eq!(0u.saturating_sub(1u), 0u);
assert_eq!((MAX-1).saturating_sub(MAX), 0);
}
#[test]
fn test_saturating_add_int() {
use int::{MIN,MAX};
assert_eq!(3i.saturating_add(5i), 8i);
assert_eq!(3i.saturating_add(MAX-1), MAX);
assert_eq!(MAX.saturating_add(MAX), MAX);
assert_eq!((MAX-2).saturating_add(1), MAX-1);
assert_eq!(3i.saturating_add(-5i), -2i);
assert_eq!(MIN.saturating_add(-1i), MIN);
assert_eq!((-2i).saturating_add(-MAX), MIN);
}
#[test]
fn test_saturating_sub_int() {
use int::{MIN,MAX};
assert_eq!(3i.saturating_sub(5i), -2i);
assert_eq!(MIN.saturating_sub(1i), MIN);
assert_eq!((-2i).saturating_sub(MAX), MIN);
assert_eq!(3i.saturating_sub(-5i), 8i);
assert_eq!(3i.saturating_sub(-(MAX-1)), MAX);
assert_eq!(MAX.saturating_sub(-MAX), MAX);
assert_eq!((MAX-2).saturating_sub(-1), MAX-1);
}
#[test]
fn test_checked_add() {
let five_less = uint::MAX - 5;
assert_eq!(five_less.checked_add(0), Some(uint::MAX - 5));
assert_eq!(five_less.checked_add(1), Some(uint::MAX - 4));
assert_eq!(five_less.checked_add(2), Some(uint::MAX - 3));
assert_eq!(five_less.checked_add(3), Some(uint::MAX - 2));
assert_eq!(five_less.checked_add(4), Some(uint::MAX - 1));
assert_eq!(five_less.checked_add(5), Some(uint::MAX));
assert_eq!(five_less.checked_add(6), None);
assert_eq!(five_less.checked_add(7), None);
}
#[test]
fn test_checked_sub() {
assert_eq!(5u.checked_sub(0), Some(5));
assert_eq!(5u.checked_sub(1), Some(4));
assert_eq!(5u.checked_sub(2), Some(3));
assert_eq!(5u.checked_sub(3), Some(2));
assert_eq!(5u.checked_sub(4), Some(1));
assert_eq!(5u.checked_sub(5), Some(0));
assert_eq!(5u.checked_sub(6), None);
assert_eq!(5u.checked_sub(7), None);
}
#[test]
fn test_checked_mul() {
let third = uint::MAX / 3;
assert_eq!(third.checked_mul(0), Some(0));
assert_eq!(third.checked_mul(1), Some(third));
assert_eq!(third.checked_mul(2), Some(third * 2));
assert_eq!(third.checked_mul(3), Some(third * 3));
assert_eq!(third.checked_mul(4), None);
}
macro_rules! test_next_power_of_two(
($test_name:ident, $T:ident) => (
fn $test_name() {
#![test]
assert_eq!((0 as $T).next_power_of_two(), 0);
let mut next_power = 1;
for i in range::<$T>(1, 40) {
assert_eq!(i.next_power_of_two(), next_power);
if i == next_power { next_power *= 2 }
}
}
)
)
test_next_power_of_two!(test_next_power_of_two_u8, u8)
test_next_power_of_two!(test_next_power_of_two_u16, u16)
test_next_power_of_two!(test_next_power_of_two_u32, u32)
test_next_power_of_two!(test_next_power_of_two_u64, u64)
test_next_power_of_two!(test_next_power_of_two_uint, uint)
macro_rules! test_checked_next_power_of_two(
($test_name:ident, $T:ident) => (
fn $test_name() {
#![test]
assert_eq!((0 as $T).checked_next_power_of_two(), None);
let mut next_power = 1;
for i in range::<$T>(1, 40) {
assert_eq!(i.checked_next_power_of_two(), Some(next_power));
if i == next_power { next_power *= 2 }
}
assert!(($T::MAX / 2).checked_next_power_of_two().is_some());
assert_eq!(($T::MAX - 1).checked_next_power_of_two(), None);
assert_eq!($T::MAX.checked_next_power_of_two(), None);
}
)
)
test_checked_next_power_of_two!(test_checked_next_power_of_two_u8, u8)
test_checked_next_power_of_two!(test_checked_next_power_of_two_u16, u16)
test_checked_next_power_of_two!(test_checked_next_power_of_two_u32, u32)
test_checked_next_power_of_two!(test_checked_next_power_of_two_u64, u64)
test_checked_next_power_of_two!(test_checked_next_power_of_two_uint, uint)
#[deriving(PartialEq, Show)]
struct Value { x: int }
impl ToPrimitive for Value {
fn to_i64(&self) -> Option<i64> { self.x.to_i64() }
fn to_u64(&self) -> Option<u64> { self.x.to_u64() }
}
impl FromPrimitive for Value {
fn from_i64(n: i64) -> Option<Value> { Some(Value { x: n as int }) }
fn from_u64(n: u64) -> Option<Value> { Some(Value { x: n as int }) }
}
#[test]
fn test_to_primitive() {
let value = Value { x: 5 };
assert_eq!(value.to_int(), Some(5));
assert_eq!(value.to_i8(), Some(5));
assert_eq!(value.to_i16(), Some(5));
assert_eq!(value.to_i32(), Some(5));
assert_eq!(value.to_i64(), Some(5));
assert_eq!(value.to_uint(), Some(5));
assert_eq!(value.to_u8(), Some(5));
assert_eq!(value.to_u16(), Some(5));
assert_eq!(value.to_u32(), Some(5));
assert_eq!(value.to_u64(), Some(5));
assert_eq!(value.to_f32(), Some(5f32));
assert_eq!(value.to_f64(), Some(5f64));
}
#[test]
fn test_from_primitive() {
assert_eq!(from_int(5), Some(Value { x: 5 }));
assert_eq!(from_i8(5), Some(Value { x: 5 }));
assert_eq!(from_i16(5), Some(Value { x: 5 }));
assert_eq!(from_i32(5), Some(Value { x: 5 }));
assert_eq!(from_i64(5), Some(Value { x: 5 }));
assert_eq!(from_uint(5), Some(Value { x: 5 }));
assert_eq!(from_u8(5), Some(Value { x: 5 }));
assert_eq!(from_u16(5), Some(Value { x: 5 }));
assert_eq!(from_u32(5), Some(Value { x: 5 }));
assert_eq!(from_u64(5), Some(Value { x: 5 }));
assert_eq!(from_f32(5f32), Some(Value { x: 5 }));
assert_eq!(from_f64(5f64), Some(Value { x: 5 }));
}
#[test]
fn test_pow() {
fn naive_pow<T: One + Mul<T, T>>(base: T, exp: uint) -> T {
range(0, exp).fold(one::<T>(), |acc, _| acc * base)
}
macro_rules! assert_pow(
(($num:expr, $exp:expr) => $expected:expr) => {{
let result = pow($num, $exp);
assert_eq!(result, $expected);
assert_eq!(result, naive_pow($num, $exp));
}}
)
assert_pow!((3i, 0 ) => 1);
assert_pow!((5i, 1 ) => 5);
assert_pow!((-4i, 2 ) => 16);
assert_pow!((8i, 3 ) => 512);
assert_pow!((2u64, 50) => 1125899906842624);
}
}
#[cfg(test)]
mod bench {
extern crate test;
use self::test::Bencher;
use num;
use prelude::*;
#[bench]
fn bench_pow_function(b: &mut Bencher) {
let v = Vec::from_fn(1024u, |n| n);
b.iter(|| {v.iter().fold(0u, |old, new| num::pow(old, *new));});
}
}