// Copyright 2012-2013 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! An interface for numeric types use cmp::{Eq, Ord}; use ops::{Neg, Add, Sub, Mul, Div, Modulo}; use option::Option; use kinds::Copy; pub mod strconv; pub trait IntConvertible { fn to_int(&self) -> int; fn from_int(n: int) -> Self; } pub trait Zero { fn zero() -> Self; } pub trait One { fn one() -> Self; } pub fn abs>(v: T) -> T { if v < Zero::zero() { v.neg() } else { v } } pub trait Round { fn round(&self, mode: RoundMode) -> Self; fn floor(&self) -> Self; fn ceil(&self) -> Self; fn fract(&self) -> Self; } pub enum RoundMode { RoundDown, RoundUp, RoundToZero, RoundFromZero } /** * Cast from one machine scalar to another * * # Example * * ~~~ * let twenty: f32 = num::cast(0x14); * assert!(twenty == 20f32); * ~~~ */ #[inline(always)] pub fn cast(n: T) -> U { NumCast::from(n) } /** * An interface for casting between machine scalars */ pub trait NumCast { fn from(n: T) -> Self; fn to_u8(&self) -> u8; fn to_u16(&self) -> u16; fn to_u32(&self) -> u32; fn to_u64(&self) -> u64; fn to_uint(&self) -> uint; fn to_i8(&self) -> i8; fn to_i16(&self) -> i16; fn to_i32(&self) -> i32; fn to_i64(&self) -> i64; fn to_int(&self) -> int; fn to_f32(&self) -> f32; fn to_f64(&self) -> f64; fn to_float(&self) -> float; } macro_rules! impl_num_cast( ($T:ty, $conv:ident) => ( // FIXME #4375: This enclosing module is necessary because // of a bug with macros expanding into multiple items pub mod $conv { use num::NumCast; #[cfg(notest)] impl NumCast for $T { #[doc = "Cast `n` to a `$T`"] #[inline(always)] fn from(n: N) -> $T { // `$conv` could be generated using `concat_idents!`, but that // macro seems to be broken at the moment n.$conv() } #[inline(always)] fn to_u8(&self) -> u8 { *self as u8 } #[inline(always)] fn to_u16(&self) -> u16 { *self as u16 } #[inline(always)] fn to_u32(&self) -> u32 { *self as u32 } #[inline(always)] fn to_u64(&self) -> u64 { *self as u64 } #[inline(always)] fn to_uint(&self) -> uint { *self as uint } #[inline(always)] fn to_i8(&self) -> i8 { *self as i8 } #[inline(always)] fn to_i16(&self) -> i16 { *self as i16 } #[inline(always)] fn to_i32(&self) -> i32 { *self as i32 } #[inline(always)] fn to_i64(&self) -> i64 { *self as i64 } #[inline(always)] fn to_int(&self) -> int { *self as int } #[inline(always)] fn to_f32(&self) -> f32 { *self as f32 } #[inline(always)] fn to_f64(&self) -> f64 { *self as f64 } #[inline(always)] fn to_float(&self) -> float { *self as float } } } ) ) impl_num_cast!(u8, to_u8) impl_num_cast!(u16, to_u16) impl_num_cast!(u32, to_u32) impl_num_cast!(u64, to_u64) impl_num_cast!(uint, to_uint) impl_num_cast!(i8, to_i8) impl_num_cast!(i16, to_i16) impl_num_cast!(i32, to_i32) impl_num_cast!(i64, to_i64) impl_num_cast!(int, to_int) impl_num_cast!(f32, to_f32) impl_num_cast!(f64, to_f64) impl_num_cast!(float, to_float) pub trait ToStrRadix { pub fn to_str_radix(&self, radix: uint) -> ~str; } pub trait FromStrRadix { pub fn from_str_radix(str: &str, radix: uint) -> Option; } // Generic math functions: /** * Calculates a power to a given radix, optimized for uint `pow` and `radix`. * * Returns `radix^pow` as `T`. * * Note: * Also returns `1` for `0^0`, despite that technically being an * undefined number. The reason for this is twofold: * - If code written to use this function cares about that special case, it's * probably going to catch it before making the call. * - If code written to use this function doesn't care about it, it's * probably assuming that `x^0` always equals `1`. */ pub fn pow_with_uint+Mul>( radix: uint, pow: uint) -> T { let _0: T = Zero::zero(); let _1: T = One::one(); if pow == 0u { return _1; } if radix == 0u { return _0; } let mut my_pow = pow; let mut total = _1; let mut multiplier = cast(radix as int); while (my_pow > 0u) { if my_pow % 2u == 1u { total *= multiplier; } my_pow /= 2u; multiplier *= multiplier; } total } macro_rules! test_cast_20( ($_20:expr) => ({ let _20 = $_20; assert!(20u == _20.to_uint()); assert!(20u8 == _20.to_u8()); assert!(20u16 == _20.to_u16()); assert!(20u32 == _20.to_u32()); assert!(20u64 == _20.to_u64()); assert!(20i == _20.to_int()); assert!(20i8 == _20.to_i8()); assert!(20i16 == _20.to_i16()); assert!(20i32 == _20.to_i32()); assert!(20i64 == _20.to_i64()); assert!(20f == _20.to_float()); assert!(20f32 == _20.to_f32()); assert!(20f64 == _20.to_f64()); assert!(_20 == NumCast::from(20u)); assert!(_20 == NumCast::from(20u8)); assert!(_20 == NumCast::from(20u16)); assert!(_20 == NumCast::from(20u32)); assert!(_20 == NumCast::from(20u64)); assert!(_20 == NumCast::from(20i)); assert!(_20 == NumCast::from(20i8)); assert!(_20 == NumCast::from(20i16)); assert!(_20 == NumCast::from(20i32)); assert!(_20 == NumCast::from(20i64)); assert!(_20 == NumCast::from(20f)); assert!(_20 == NumCast::from(20f32)); assert!(_20 == NumCast::from(20f64)); assert!(_20 == cast(20u)); assert!(_20 == cast(20u8)); assert!(_20 == cast(20u16)); assert!(_20 == cast(20u32)); assert!(_20 == cast(20u64)); assert!(_20 == cast(20i)); assert!(_20 == cast(20i8)); assert!(_20 == cast(20i16)); assert!(_20 == cast(20i32)); assert!(_20 == cast(20i64)); assert!(_20 == cast(20f)); assert!(_20 == cast(20f32)); assert!(_20 == cast(20f64)); }) ) #[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_float_cast() { test_cast_20!(20f) }