1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Numeric traits and functions for generic mathematics
13 //! These are implemented for the primitive numeric types in `std::{u8, u16,
14 //! u32, u64, uint, i8, i16, i32, i64, int, f32, f64}`.
17 #![allow(missing_docs)]
19 #[cfg(test)] use cmp::PartialEq;
20 #[cfg(test)] use fmt::Show;
21 #[cfg(test)] use ops::{Add, Sub, Mul, Div, Rem};
22 #[cfg(test)] use kinds::Copy;
24 pub use core::num::{Int, SignedInt, UnsignedInt};
25 pub use core::num::{cast, FromPrimitive, NumCast, ToPrimitive};
26 pub use core::num::{from_int, from_i8, from_i16, from_i32, from_i64};
27 pub use core::num::{from_uint, from_u8, from_u16, from_u32, from_u64};
28 pub use core::num::{from_f32, from_f64};
29 pub use core::num::{FromStrRadix, from_str_radix};
30 pub use core::num::{FpCategory, Float};
32 #[experimental = "may be removed or relocated"]
35 /// Mathematical operations on primitive floating point numbers.
36 #[unstable = "may be altered to inline the Float trait"]
37 pub trait FloatMath: Float {
38 /// Constructs a floating point number created by multiplying `x` by 2
39 /// raised to the power of `exp`.
40 fn ldexp(x: Self, exp: int) -> Self;
41 /// Breaks the number into a normalized fraction and a base-2 exponent,
44 /// * `self = x * pow(2, exp)`
46 /// * `0.5 <= abs(x) < 1.0`
47 fn frexp(self) -> (Self, int);
49 /// Returns the next representable floating-point value in the direction of
51 fn next_after(self, other: Self) -> Self;
53 /// Returns the maximum of the two numbers.
54 fn max(self, other: Self) -> Self;
55 /// Returns the minimum of the two numbers.
56 fn min(self, other: Self) -> Self;
58 /// The positive difference of two numbers. Returns `0.0` if the number is
59 /// less than or equal to `other`, otherwise the difference between`self`
60 /// and `other` is returned.
61 fn abs_sub(self, other: Self) -> Self;
63 /// Take the cubic root of a number.
64 fn cbrt(self) -> Self;
65 /// Calculate the length of the hypotenuse of a right-angle triangle given
66 /// legs of length `x` and `y`.
67 fn hypot(self, other: Self) -> Self;
69 /// Computes the sine of a number (in radians).
71 /// Computes the cosine of a number (in radians).
73 /// Computes the tangent of a number (in radians).
76 /// Computes the arcsine of a number. Return value is in radians in
77 /// the range [-pi/2, pi/2] or NaN if the number is outside the range
79 fn asin(self) -> Self;
80 /// Computes the arccosine of a number. Return value is in radians in
81 /// the range [0, pi] or NaN if the number is outside the range
83 fn acos(self) -> Self;
84 /// Computes the arctangent of a number. Return value is in radians in the
85 /// range [-pi/2, pi/2];
86 fn atan(self) -> Self;
87 /// Computes the four quadrant arctangent of a number, `y`, and another
88 /// number `x`. Return value is in radians in the range [-pi, pi].
89 fn atan2(self, other: Self) -> Self;
90 /// Simultaneously computes the sine and cosine of the number, `x`. Returns
91 /// `(sin(x), cos(x))`.
92 fn sin_cos(self) -> (Self, Self);
94 /// Returns the exponential of the number, minus 1, in a way that is
95 /// accurate even if the number is close to zero.
96 fn exp_m1(self) -> Self;
97 /// Returns the natural logarithm of the number plus 1 (`ln(1+n)`) more
98 /// accurately than if the operations were performed separately.
99 fn ln_1p(self) -> Self;
101 /// Hyperbolic sine function.
102 fn sinh(self) -> Self;
103 /// Hyperbolic cosine function.
104 fn cosh(self) -> Self;
105 /// Hyperbolic tangent function.
106 fn tanh(self) -> Self;
107 /// Inverse hyperbolic sine function.
108 fn asinh(self) -> Self;
109 /// Inverse hyperbolic cosine function.
110 fn acosh(self) -> Self;
111 /// Inverse hyperbolic tangent function.
112 fn atanh(self) -> Self;
117 /// Helper function for testing numeric operations
119 pub fn test_num<T>(ten: T, two: T) where
120 T: PartialEq + NumCast
121 + Add<Output=T> + Sub<Output=T>
122 + Mul<Output=T> + Div<Output=T>
123 + Rem<Output=T> + Show
126 assert_eq!(ten.add(two), cast(12i).unwrap());
127 assert_eq!(ten.sub(two), cast(8i).unwrap());
128 assert_eq!(ten.mul(two), cast(20i).unwrap());
129 assert_eq!(ten.div(two), cast(5i).unwrap());
130 assert_eq!(ten.rem(two), cast(0i).unwrap());
132 assert_eq!(ten.add(two), ten + two);
133 assert_eq!(ten.sub(two), ten - two);
134 assert_eq!(ten.mul(two), ten * two);
135 assert_eq!(ten.div(two), ten / two);
136 assert_eq!(ten.rem(two), ten % two);
154 macro_rules! test_cast_20 {
158 assert_eq!(20u, _20.to_uint().unwrap());
159 assert_eq!(20u8, _20.to_u8().unwrap());
160 assert_eq!(20u16, _20.to_u16().unwrap());
161 assert_eq!(20u32, _20.to_u32().unwrap());
162 assert_eq!(20u64, _20.to_u64().unwrap());
163 assert_eq!(20i, _20.to_int().unwrap());
164 assert_eq!(20i8, _20.to_i8().unwrap());
165 assert_eq!(20i16, _20.to_i16().unwrap());
166 assert_eq!(20i32, _20.to_i32().unwrap());
167 assert_eq!(20i64, _20.to_i64().unwrap());
168 assert_eq!(20f32, _20.to_f32().unwrap());
169 assert_eq!(20f64, _20.to_f64().unwrap());
171 assert_eq!(_20, NumCast::from(20u).unwrap());
172 assert_eq!(_20, NumCast::from(20u8).unwrap());
173 assert_eq!(_20, NumCast::from(20u16).unwrap());
174 assert_eq!(_20, NumCast::from(20u32).unwrap());
175 assert_eq!(_20, NumCast::from(20u64).unwrap());
176 assert_eq!(_20, NumCast::from(20i).unwrap());
177 assert_eq!(_20, NumCast::from(20i8).unwrap());
178 assert_eq!(_20, NumCast::from(20i16).unwrap());
179 assert_eq!(_20, NumCast::from(20i32).unwrap());
180 assert_eq!(_20, NumCast::from(20i64).unwrap());
181 assert_eq!(_20, NumCast::from(20f32).unwrap());
182 assert_eq!(_20, NumCast::from(20f64).unwrap());
184 assert_eq!(_20, cast(20u).unwrap());
185 assert_eq!(_20, cast(20u8).unwrap());
186 assert_eq!(_20, cast(20u16).unwrap());
187 assert_eq!(_20, cast(20u32).unwrap());
188 assert_eq!(_20, cast(20u64).unwrap());
189 assert_eq!(_20, cast(20i).unwrap());
190 assert_eq!(_20, cast(20i8).unwrap());
191 assert_eq!(_20, cast(20i16).unwrap());
192 assert_eq!(_20, cast(20i32).unwrap());
193 assert_eq!(_20, cast(20i64).unwrap());
194 assert_eq!(_20, cast(20f32).unwrap());
195 assert_eq!(_20, cast(20f64).unwrap());
199 #[test] fn test_u8_cast() { test_cast_20!(20u8) }
200 #[test] fn test_u16_cast() { test_cast_20!(20u16) }
201 #[test] fn test_u32_cast() { test_cast_20!(20u32) }
202 #[test] fn test_u64_cast() { test_cast_20!(20u64) }
203 #[test] fn test_uint_cast() { test_cast_20!(20u) }
204 #[test] fn test_i8_cast() { test_cast_20!(20i8) }
205 #[test] fn test_i16_cast() { test_cast_20!(20i16) }
206 #[test] fn test_i32_cast() { test_cast_20!(20i32) }
207 #[test] fn test_i64_cast() { test_cast_20!(20i64) }
208 #[test] fn test_int_cast() { test_cast_20!(20i) }
209 #[test] fn test_f32_cast() { test_cast_20!(20f32) }
210 #[test] fn test_f64_cast() { test_cast_20!(20f64) }
213 fn test_cast_range_int_min() {
214 assert_eq!(int::MIN.to_int(), Some(int::MIN as int));
215 assert_eq!(int::MIN.to_i8(), None);
216 assert_eq!(int::MIN.to_i16(), None);
217 // int::MIN.to_i32() is word-size specific
218 assert_eq!(int::MIN.to_i64(), Some(int::MIN as i64));
219 assert_eq!(int::MIN.to_uint(), None);
220 assert_eq!(int::MIN.to_u8(), None);
221 assert_eq!(int::MIN.to_u16(), None);
222 assert_eq!(int::MIN.to_u32(), None);
223 assert_eq!(int::MIN.to_u64(), None);
225 #[cfg(target_word_size = "32")]
226 fn check_word_size() {
227 assert_eq!(int::MIN.to_i32(), Some(int::MIN as i32));
230 #[cfg(target_word_size = "64")]
231 fn check_word_size() {
232 assert_eq!(int::MIN.to_i32(), None);
239 fn test_cast_range_i8_min() {
240 assert_eq!(i8::MIN.to_int(), Some(i8::MIN as int));
241 assert_eq!(i8::MIN.to_i8(), Some(i8::MIN as i8));
242 assert_eq!(i8::MIN.to_i16(), Some(i8::MIN as i16));
243 assert_eq!(i8::MIN.to_i32(), Some(i8::MIN as i32));
244 assert_eq!(i8::MIN.to_i64(), Some(i8::MIN as i64));
245 assert_eq!(i8::MIN.to_uint(), None);
246 assert_eq!(i8::MIN.to_u8(), None);
247 assert_eq!(i8::MIN.to_u16(), None);
248 assert_eq!(i8::MIN.to_u32(), None);
249 assert_eq!(i8::MIN.to_u64(), None);
253 fn test_cast_range_i16_min() {
254 assert_eq!(i16::MIN.to_int(), Some(i16::MIN as int));
255 assert_eq!(i16::MIN.to_i8(), None);
256 assert_eq!(i16::MIN.to_i16(), Some(i16::MIN as i16));
257 assert_eq!(i16::MIN.to_i32(), Some(i16::MIN as i32));
258 assert_eq!(i16::MIN.to_i64(), Some(i16::MIN as i64));
259 assert_eq!(i16::MIN.to_uint(), None);
260 assert_eq!(i16::MIN.to_u8(), None);
261 assert_eq!(i16::MIN.to_u16(), None);
262 assert_eq!(i16::MIN.to_u32(), None);
263 assert_eq!(i16::MIN.to_u64(), None);
267 fn test_cast_range_i32_min() {
268 assert_eq!(i32::MIN.to_int(), Some(i32::MIN as int));
269 assert_eq!(i32::MIN.to_i8(), None);
270 assert_eq!(i32::MIN.to_i16(), None);
271 assert_eq!(i32::MIN.to_i32(), Some(i32::MIN as i32));
272 assert_eq!(i32::MIN.to_i64(), Some(i32::MIN as i64));
273 assert_eq!(i32::MIN.to_uint(), None);
274 assert_eq!(i32::MIN.to_u8(), None);
275 assert_eq!(i32::MIN.to_u16(), None);
276 assert_eq!(i32::MIN.to_u32(), None);
277 assert_eq!(i32::MIN.to_u64(), None);
281 fn test_cast_range_i64_min() {
282 // i64::MIN.to_int() is word-size specific
283 assert_eq!(i64::MIN.to_i8(), None);
284 assert_eq!(i64::MIN.to_i16(), None);
285 assert_eq!(i64::MIN.to_i32(), None);
286 assert_eq!(i64::MIN.to_i64(), Some(i64::MIN as i64));
287 assert_eq!(i64::MIN.to_uint(), None);
288 assert_eq!(i64::MIN.to_u8(), None);
289 assert_eq!(i64::MIN.to_u16(), None);
290 assert_eq!(i64::MIN.to_u32(), None);
291 assert_eq!(i64::MIN.to_u64(), None);
293 #[cfg(target_word_size = "32")]
294 fn check_word_size() {
295 assert_eq!(i64::MIN.to_int(), None);
298 #[cfg(target_word_size = "64")]
299 fn check_word_size() {
300 assert_eq!(i64::MIN.to_int(), Some(i64::MIN as int));
307 fn test_cast_range_int_max() {
308 assert_eq!(int::MAX.to_int(), Some(int::MAX as int));
309 assert_eq!(int::MAX.to_i8(), None);
310 assert_eq!(int::MAX.to_i16(), None);
311 // int::MAX.to_i32() is word-size specific
312 assert_eq!(int::MAX.to_i64(), Some(int::MAX as i64));
313 assert_eq!(int::MAX.to_u8(), None);
314 assert_eq!(int::MAX.to_u16(), None);
315 // int::MAX.to_u32() is word-size specific
316 assert_eq!(int::MAX.to_u64(), Some(int::MAX as u64));
318 #[cfg(target_word_size = "32")]
319 fn check_word_size() {
320 assert_eq!(int::MAX.to_i32(), Some(int::MAX as i32));
321 assert_eq!(int::MAX.to_u32(), Some(int::MAX as u32));
324 #[cfg(target_word_size = "64")]
325 fn check_word_size() {
326 assert_eq!(int::MAX.to_i32(), None);
327 assert_eq!(int::MAX.to_u32(), None);
334 fn test_cast_range_i8_max() {
335 assert_eq!(i8::MAX.to_int(), Some(i8::MAX as int));
336 assert_eq!(i8::MAX.to_i8(), Some(i8::MAX as i8));
337 assert_eq!(i8::MAX.to_i16(), Some(i8::MAX as i16));
338 assert_eq!(i8::MAX.to_i32(), Some(i8::MAX as i32));
339 assert_eq!(i8::MAX.to_i64(), Some(i8::MAX as i64));
340 assert_eq!(i8::MAX.to_uint(), Some(i8::MAX as uint));
341 assert_eq!(i8::MAX.to_u8(), Some(i8::MAX as u8));
342 assert_eq!(i8::MAX.to_u16(), Some(i8::MAX as u16));
343 assert_eq!(i8::MAX.to_u32(), Some(i8::MAX as u32));
344 assert_eq!(i8::MAX.to_u64(), Some(i8::MAX as u64));
348 fn test_cast_range_i16_max() {
349 assert_eq!(i16::MAX.to_int(), Some(i16::MAX as int));
350 assert_eq!(i16::MAX.to_i8(), None);
351 assert_eq!(i16::MAX.to_i16(), Some(i16::MAX as i16));
352 assert_eq!(i16::MAX.to_i32(), Some(i16::MAX as i32));
353 assert_eq!(i16::MAX.to_i64(), Some(i16::MAX as i64));
354 assert_eq!(i16::MAX.to_uint(), Some(i16::MAX as uint));
355 assert_eq!(i16::MAX.to_u8(), None);
356 assert_eq!(i16::MAX.to_u16(), Some(i16::MAX as u16));
357 assert_eq!(i16::MAX.to_u32(), Some(i16::MAX as u32));
358 assert_eq!(i16::MAX.to_u64(), Some(i16::MAX as u64));
362 fn test_cast_range_i32_max() {
363 assert_eq!(i32::MAX.to_int(), Some(i32::MAX as int));
364 assert_eq!(i32::MAX.to_i8(), None);
365 assert_eq!(i32::MAX.to_i16(), None);
366 assert_eq!(i32::MAX.to_i32(), Some(i32::MAX as i32));
367 assert_eq!(i32::MAX.to_i64(), Some(i32::MAX as i64));
368 assert_eq!(i32::MAX.to_uint(), Some(i32::MAX as uint));
369 assert_eq!(i32::MAX.to_u8(), None);
370 assert_eq!(i32::MAX.to_u16(), None);
371 assert_eq!(i32::MAX.to_u32(), Some(i32::MAX as u32));
372 assert_eq!(i32::MAX.to_u64(), Some(i32::MAX as u64));
376 fn test_cast_range_i64_max() {
377 // i64::MAX.to_int() is word-size specific
378 assert_eq!(i64::MAX.to_i8(), None);
379 assert_eq!(i64::MAX.to_i16(), None);
380 assert_eq!(i64::MAX.to_i32(), None);
381 assert_eq!(i64::MAX.to_i64(), Some(i64::MAX as i64));
382 // i64::MAX.to_uint() is word-size specific
383 assert_eq!(i64::MAX.to_u8(), None);
384 assert_eq!(i64::MAX.to_u16(), None);
385 assert_eq!(i64::MAX.to_u32(), None);
386 assert_eq!(i64::MAX.to_u64(), Some(i64::MAX as u64));
388 #[cfg(target_word_size = "32")]
389 fn check_word_size() {
390 assert_eq!(i64::MAX.to_int(), None);
391 assert_eq!(i64::MAX.to_uint(), None);
394 #[cfg(target_word_size = "64")]
395 fn check_word_size() {
396 assert_eq!(i64::MAX.to_int(), Some(i64::MAX as int));
397 assert_eq!(i64::MAX.to_uint(), Some(i64::MAX as uint));
404 fn test_cast_range_uint_min() {
405 assert_eq!(uint::MIN.to_int(), Some(uint::MIN as int));
406 assert_eq!(uint::MIN.to_i8(), Some(uint::MIN as i8));
407 assert_eq!(uint::MIN.to_i16(), Some(uint::MIN as i16));
408 assert_eq!(uint::MIN.to_i32(), Some(uint::MIN as i32));
409 assert_eq!(uint::MIN.to_i64(), Some(uint::MIN as i64));
410 assert_eq!(uint::MIN.to_uint(), Some(uint::MIN as uint));
411 assert_eq!(uint::MIN.to_u8(), Some(uint::MIN as u8));
412 assert_eq!(uint::MIN.to_u16(), Some(uint::MIN as u16));
413 assert_eq!(uint::MIN.to_u32(), Some(uint::MIN as u32));
414 assert_eq!(uint::MIN.to_u64(), Some(uint::MIN as u64));
418 fn test_cast_range_u8_min() {
419 assert_eq!(u8::MIN.to_int(), Some(u8::MIN as int));
420 assert_eq!(u8::MIN.to_i8(), Some(u8::MIN as i8));
421 assert_eq!(u8::MIN.to_i16(), Some(u8::MIN as i16));
422 assert_eq!(u8::MIN.to_i32(), Some(u8::MIN as i32));
423 assert_eq!(u8::MIN.to_i64(), Some(u8::MIN as i64));
424 assert_eq!(u8::MIN.to_uint(), Some(u8::MIN as uint));
425 assert_eq!(u8::MIN.to_u8(), Some(u8::MIN as u8));
426 assert_eq!(u8::MIN.to_u16(), Some(u8::MIN as u16));
427 assert_eq!(u8::MIN.to_u32(), Some(u8::MIN as u32));
428 assert_eq!(u8::MIN.to_u64(), Some(u8::MIN as u64));
432 fn test_cast_range_u16_min() {
433 assert_eq!(u16::MIN.to_int(), Some(u16::MIN as int));
434 assert_eq!(u16::MIN.to_i8(), Some(u16::MIN as i8));
435 assert_eq!(u16::MIN.to_i16(), Some(u16::MIN as i16));
436 assert_eq!(u16::MIN.to_i32(), Some(u16::MIN as i32));
437 assert_eq!(u16::MIN.to_i64(), Some(u16::MIN as i64));
438 assert_eq!(u16::MIN.to_uint(), Some(u16::MIN as uint));
439 assert_eq!(u16::MIN.to_u8(), Some(u16::MIN as u8));
440 assert_eq!(u16::MIN.to_u16(), Some(u16::MIN as u16));
441 assert_eq!(u16::MIN.to_u32(), Some(u16::MIN as u32));
442 assert_eq!(u16::MIN.to_u64(), Some(u16::MIN as u64));
446 fn test_cast_range_u32_min() {
447 assert_eq!(u32::MIN.to_int(), Some(u32::MIN as int));
448 assert_eq!(u32::MIN.to_i8(), Some(u32::MIN as i8));
449 assert_eq!(u32::MIN.to_i16(), Some(u32::MIN as i16));
450 assert_eq!(u32::MIN.to_i32(), Some(u32::MIN as i32));
451 assert_eq!(u32::MIN.to_i64(), Some(u32::MIN as i64));
452 assert_eq!(u32::MIN.to_uint(), Some(u32::MIN as uint));
453 assert_eq!(u32::MIN.to_u8(), Some(u32::MIN as u8));
454 assert_eq!(u32::MIN.to_u16(), Some(u32::MIN as u16));
455 assert_eq!(u32::MIN.to_u32(), Some(u32::MIN as u32));
456 assert_eq!(u32::MIN.to_u64(), Some(u32::MIN as u64));
460 fn test_cast_range_u64_min() {
461 assert_eq!(u64::MIN.to_int(), Some(u64::MIN as int));
462 assert_eq!(u64::MIN.to_i8(), Some(u64::MIN as i8));
463 assert_eq!(u64::MIN.to_i16(), Some(u64::MIN as i16));
464 assert_eq!(u64::MIN.to_i32(), Some(u64::MIN as i32));
465 assert_eq!(u64::MIN.to_i64(), Some(u64::MIN as i64));
466 assert_eq!(u64::MIN.to_uint(), Some(u64::MIN as uint));
467 assert_eq!(u64::MIN.to_u8(), Some(u64::MIN as u8));
468 assert_eq!(u64::MIN.to_u16(), Some(u64::MIN as u16));
469 assert_eq!(u64::MIN.to_u32(), Some(u64::MIN as u32));
470 assert_eq!(u64::MIN.to_u64(), Some(u64::MIN as u64));
474 fn test_cast_range_uint_max() {
475 assert_eq!(uint::MAX.to_int(), None);
476 assert_eq!(uint::MAX.to_i8(), None);
477 assert_eq!(uint::MAX.to_i16(), None);
478 assert_eq!(uint::MAX.to_i32(), None);
479 // uint::MAX.to_i64() is word-size specific
480 assert_eq!(uint::MAX.to_u8(), None);
481 assert_eq!(uint::MAX.to_u16(), None);
482 // uint::MAX.to_u32() is word-size specific
483 assert_eq!(uint::MAX.to_u64(), Some(uint::MAX as u64));
485 #[cfg(target_word_size = "32")]
486 fn check_word_size() {
487 assert_eq!(uint::MAX.to_u32(), Some(uint::MAX as u32));
488 assert_eq!(uint::MAX.to_i64(), Some(uint::MAX as i64));
491 #[cfg(target_word_size = "64")]
492 fn check_word_size() {
493 assert_eq!(uint::MAX.to_u32(), None);
494 assert_eq!(uint::MAX.to_i64(), None);
501 fn test_cast_range_u8_max() {
502 assert_eq!(u8::MAX.to_int(), Some(u8::MAX as int));
503 assert_eq!(u8::MAX.to_i8(), None);
504 assert_eq!(u8::MAX.to_i16(), Some(u8::MAX as i16));
505 assert_eq!(u8::MAX.to_i32(), Some(u8::MAX as i32));
506 assert_eq!(u8::MAX.to_i64(), Some(u8::MAX as i64));
507 assert_eq!(u8::MAX.to_uint(), Some(u8::MAX as uint));
508 assert_eq!(u8::MAX.to_u8(), Some(u8::MAX as u8));
509 assert_eq!(u8::MAX.to_u16(), Some(u8::MAX as u16));
510 assert_eq!(u8::MAX.to_u32(), Some(u8::MAX as u32));
511 assert_eq!(u8::MAX.to_u64(), Some(u8::MAX as u64));
515 fn test_cast_range_u16_max() {
516 assert_eq!(u16::MAX.to_int(), Some(u16::MAX as int));
517 assert_eq!(u16::MAX.to_i8(), None);
518 assert_eq!(u16::MAX.to_i16(), None);
519 assert_eq!(u16::MAX.to_i32(), Some(u16::MAX as i32));
520 assert_eq!(u16::MAX.to_i64(), Some(u16::MAX as i64));
521 assert_eq!(u16::MAX.to_uint(), Some(u16::MAX as uint));
522 assert_eq!(u16::MAX.to_u8(), None);
523 assert_eq!(u16::MAX.to_u16(), Some(u16::MAX as u16));
524 assert_eq!(u16::MAX.to_u32(), Some(u16::MAX as u32));
525 assert_eq!(u16::MAX.to_u64(), Some(u16::MAX as u64));
529 fn test_cast_range_u32_max() {
530 // u32::MAX.to_int() is word-size specific
531 assert_eq!(u32::MAX.to_i8(), None);
532 assert_eq!(u32::MAX.to_i16(), None);
533 assert_eq!(u32::MAX.to_i32(), None);
534 assert_eq!(u32::MAX.to_i64(), Some(u32::MAX as i64));
535 assert_eq!(u32::MAX.to_uint(), Some(u32::MAX as uint));
536 assert_eq!(u32::MAX.to_u8(), None);
537 assert_eq!(u32::MAX.to_u16(), None);
538 assert_eq!(u32::MAX.to_u32(), Some(u32::MAX as u32));
539 assert_eq!(u32::MAX.to_u64(), Some(u32::MAX as u64));
541 #[cfg(target_word_size = "32")]
542 fn check_word_size() {
543 assert_eq!(u32::MAX.to_int(), None);
546 #[cfg(target_word_size = "64")]
547 fn check_word_size() {
548 assert_eq!(u32::MAX.to_int(), Some(u32::MAX as int));
555 fn test_cast_range_u64_max() {
556 assert_eq!(u64::MAX.to_int(), None);
557 assert_eq!(u64::MAX.to_i8(), None);
558 assert_eq!(u64::MAX.to_i16(), None);
559 assert_eq!(u64::MAX.to_i32(), None);
560 assert_eq!(u64::MAX.to_i64(), None);
561 // u64::MAX.to_uint() is word-size specific
562 assert_eq!(u64::MAX.to_u8(), None);
563 assert_eq!(u64::MAX.to_u16(), None);
564 assert_eq!(u64::MAX.to_u32(), None);
565 assert_eq!(u64::MAX.to_u64(), Some(u64::MAX as u64));
567 #[cfg(target_word_size = "32")]
568 fn check_word_size() {
569 assert_eq!(u64::MAX.to_uint(), None);
572 #[cfg(target_word_size = "64")]
573 fn check_word_size() {
574 assert_eq!(u64::MAX.to_uint(), Some(u64::MAX as uint));
581 fn test_saturating_add_uint() {
583 assert_eq!(3u.saturating_add(5u), 8u);
584 assert_eq!(3u.saturating_add(MAX-1), MAX);
585 assert_eq!(MAX.saturating_add(MAX), MAX);
586 assert_eq!((MAX-2).saturating_add(1), MAX-1);
590 fn test_saturating_sub_uint() {
592 assert_eq!(5u.saturating_sub(3u), 2u);
593 assert_eq!(3u.saturating_sub(5u), 0u);
594 assert_eq!(0u.saturating_sub(1u), 0u);
595 assert_eq!((MAX-1).saturating_sub(MAX), 0);
599 fn test_saturating_add_int() {
601 assert_eq!(3i.saturating_add(5i), 8i);
602 assert_eq!(3i.saturating_add(MAX-1), MAX);
603 assert_eq!(MAX.saturating_add(MAX), MAX);
604 assert_eq!((MAX-2).saturating_add(1), MAX-1);
605 assert_eq!(3i.saturating_add(-5i), -2i);
606 assert_eq!(MIN.saturating_add(-1i), MIN);
607 assert_eq!((-2i).saturating_add(-MAX), MIN);
611 fn test_saturating_sub_int() {
613 assert_eq!(3i.saturating_sub(5i), -2i);
614 assert_eq!(MIN.saturating_sub(1i), MIN);
615 assert_eq!((-2i).saturating_sub(MAX), MIN);
616 assert_eq!(3i.saturating_sub(-5i), 8i);
617 assert_eq!(3i.saturating_sub(-(MAX-1)), MAX);
618 assert_eq!(MAX.saturating_sub(-MAX), MAX);
619 assert_eq!((MAX-2).saturating_sub(-1), MAX-1);
623 fn test_checked_add() {
624 let five_less = uint::MAX - 5;
625 assert_eq!(five_less.checked_add(0), Some(uint::MAX - 5));
626 assert_eq!(five_less.checked_add(1), Some(uint::MAX - 4));
627 assert_eq!(five_less.checked_add(2), Some(uint::MAX - 3));
628 assert_eq!(five_less.checked_add(3), Some(uint::MAX - 2));
629 assert_eq!(five_less.checked_add(4), Some(uint::MAX - 1));
630 assert_eq!(five_less.checked_add(5), Some(uint::MAX));
631 assert_eq!(five_less.checked_add(6), None);
632 assert_eq!(five_less.checked_add(7), None);
636 fn test_checked_sub() {
637 assert_eq!(5u.checked_sub(0), Some(5));
638 assert_eq!(5u.checked_sub(1), Some(4));
639 assert_eq!(5u.checked_sub(2), Some(3));
640 assert_eq!(5u.checked_sub(3), Some(2));
641 assert_eq!(5u.checked_sub(4), Some(1));
642 assert_eq!(5u.checked_sub(5), Some(0));
643 assert_eq!(5u.checked_sub(6), None);
644 assert_eq!(5u.checked_sub(7), None);
648 fn test_checked_mul() {
649 let third = uint::MAX / 3;
650 assert_eq!(third.checked_mul(0), Some(0));
651 assert_eq!(third.checked_mul(1), Some(third));
652 assert_eq!(third.checked_mul(2), Some(third * 2));
653 assert_eq!(third.checked_mul(3), Some(third * 3));
654 assert_eq!(third.checked_mul(4), None);
657 macro_rules! test_is_power_of_two {
658 ($test_name:ident, $T:ident) => (
661 assert_eq!((0 as $T).is_power_of_two(), false);
662 assert_eq!((1 as $T).is_power_of_two(), true);
663 assert_eq!((2 as $T).is_power_of_two(), true);
664 assert_eq!((3 as $T).is_power_of_two(), false);
665 assert_eq!((4 as $T).is_power_of_two(), true);
666 assert_eq!((5 as $T).is_power_of_two(), false);
667 assert!(($T::MAX / 2 + 1).is_power_of_two(), true);
672 test_is_power_of_two!{ test_is_power_of_two_u8, u8 }
673 test_is_power_of_two!{ test_is_power_of_two_u16, u16 }
674 test_is_power_of_two!{ test_is_power_of_two_u32, u32 }
675 test_is_power_of_two!{ test_is_power_of_two_u64, u64 }
676 test_is_power_of_two!{ test_is_power_of_two_uint, uint }
678 macro_rules! test_next_power_of_two {
679 ($test_name:ident, $T:ident) => (
682 assert_eq!((0 as $T).next_power_of_two(), 1);
683 let mut next_power = 1;
684 for i in range::<$T>(1, 40) {
685 assert_eq!(i.next_power_of_two(), next_power);
686 if i == next_power { next_power *= 2 }
692 test_next_power_of_two! { test_next_power_of_two_u8, u8 }
693 test_next_power_of_two! { test_next_power_of_two_u16, u16 }
694 test_next_power_of_two! { test_next_power_of_two_u32, u32 }
695 test_next_power_of_two! { test_next_power_of_two_u64, u64 }
696 test_next_power_of_two! { test_next_power_of_two_uint, uint }
698 macro_rules! test_checked_next_power_of_two {
699 ($test_name:ident, $T:ident) => (
702 assert_eq!((0 as $T).checked_next_power_of_two(), Some(1));
703 assert!(($T::MAX / 2).checked_next_power_of_two().is_some());
704 assert_eq!(($T::MAX - 1).checked_next_power_of_two(), None);
705 assert_eq!($T::MAX.checked_next_power_of_two(), None);
706 let mut next_power = 1;
707 for i in range::<$T>(1, 40) {
708 assert_eq!(i.checked_next_power_of_two(), Some(next_power));
709 if i == next_power { next_power *= 2 }
715 test_checked_next_power_of_two! { test_checked_next_power_of_two_u8, u8 }
716 test_checked_next_power_of_two! { test_checked_next_power_of_two_u16, u16 }
717 test_checked_next_power_of_two! { test_checked_next_power_of_two_u32, u32 }
718 test_checked_next_power_of_two! { test_checked_next_power_of_two_u64, u64 }
719 test_checked_next_power_of_two! { test_checked_next_power_of_two_uint, uint }
721 #[derive(PartialEq, Show)]
722 struct Value { x: int }
724 impl ToPrimitive for Value {
725 fn to_i64(&self) -> Option<i64> { self.x.to_i64() }
726 fn to_u64(&self) -> Option<u64> { self.x.to_u64() }
729 impl FromPrimitive for Value {
730 fn from_i64(n: i64) -> Option<Value> { Some(Value { x: n as int }) }
731 fn from_u64(n: u64) -> Option<Value> { Some(Value { x: n as int }) }
735 fn test_to_primitive() {
736 let value = Value { x: 5 };
737 assert_eq!(value.to_int(), Some(5));
738 assert_eq!(value.to_i8(), Some(5));
739 assert_eq!(value.to_i16(), Some(5));
740 assert_eq!(value.to_i32(), Some(5));
741 assert_eq!(value.to_i64(), Some(5));
742 assert_eq!(value.to_uint(), Some(5));
743 assert_eq!(value.to_u8(), Some(5));
744 assert_eq!(value.to_u16(), Some(5));
745 assert_eq!(value.to_u32(), Some(5));
746 assert_eq!(value.to_u64(), Some(5));
747 assert_eq!(value.to_f32(), Some(5f32));
748 assert_eq!(value.to_f64(), Some(5f64));
752 fn test_from_primitive() {
753 assert_eq!(from_int(5), Some(Value { x: 5 }));
754 assert_eq!(from_i8(5), Some(Value { x: 5 }));
755 assert_eq!(from_i16(5), Some(Value { x: 5 }));
756 assert_eq!(from_i32(5), Some(Value { x: 5 }));
757 assert_eq!(from_i64(5), Some(Value { x: 5 }));
758 assert_eq!(from_uint(5), Some(Value { x: 5 }));
759 assert_eq!(from_u8(5), Some(Value { x: 5 }));
760 assert_eq!(from_u16(5), Some(Value { x: 5 }));
761 assert_eq!(from_u32(5), Some(Value { x: 5 }));
762 assert_eq!(from_u64(5), Some(Value { x: 5 }));
763 assert_eq!(from_f32(5f32), Some(Value { x: 5 }));
764 assert_eq!(from_f64(5f64), Some(Value { x: 5 }));
769 fn naive_pow<T: Int>(base: T, exp: uint) -> T {
770 let one: T = Int::one();
771 range(0, exp).fold(one, |acc, _| acc * base)
773 macro_rules! assert_pow {
774 (($num:expr, $exp:expr) => $expected:expr) => {{
775 let result = $num.pow($exp);
776 assert_eq!(result, $expected);
777 assert_eq!(result, naive_pow($num, $exp));
780 assert_pow!((3i, 0 ) => 1);
781 assert_pow!((5i, 1 ) => 5);
782 assert_pow!((-4i, 2 ) => 16);
783 assert_pow!((8i, 3 ) => 512);
784 assert_pow!((2u64, 50) => 1125899906842624);
792 use self::test::Bencher;
797 fn bench_pow_function(b: &mut Bencher) {
798 let v = range(0, 1024u).collect::<Vec<_>>();
799 b.iter(|| {v.iter().fold(0u, |old, new| old.pow(*new));});