1use crate::num::TryFromIntError;
2
3mod private {
4 #[unstable(feature = "convert_float_to_int", issue = "67057")]
8 pub trait Sealed {}
9}
10
11#[unstable(feature = "convert_float_to_int", issue = "67057")]
14pub trait FloatToInt<Int>: private::Sealed + Sized {
15 #[unstable(feature = "convert_float_to_int", issue = "67057")]
16 #[doc(hidden)]
17 unsafe fn to_int_unchecked(self) -> Int;
18}
19
20macro_rules! impl_float_to_int {
21 ($Float:ty => $($Int:ty),+) => {
22 #[unstable(feature = "convert_float_to_int", issue = "67057")]
23 impl private::Sealed for $Float {}
24 $(
25 #[unstable(feature = "convert_float_to_int", issue = "67057")]
26 impl FloatToInt<$Int> for $Float {
27 #[inline]
28 unsafe fn to_int_unchecked(self) -> $Int {
29 unsafe { crate::intrinsics::float_to_int_unchecked(self) }
31 }
32 }
33 )+
34 }
35}
36
37impl_float_to_int!(f16 => u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
38impl_float_to_int!(f32 => u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
39impl_float_to_int!(f64 => u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
40impl_float_to_int!(f128 => u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
41
42macro_rules! impl_from {
46 (bool => $Int:ty $(,)?) => {
47 impl_from!(
48 bool => $Int,
49 #[stable(feature = "from_bool", since = "1.28.0")],
50 concat!(
51 "Converts a [`bool`] to [`", stringify!($Int), "`] losslessly.\n",
52 "The resulting value is `0` for `false` and `1` for `true` values.\n",
53 "\n",
54 "# Examples\n",
55 "\n",
56 "```\n",
57 "assert_eq!(", stringify!($Int), "::from(true), 1);\n",
58 "assert_eq!(", stringify!($Int), "::from(false), 0);\n",
59 "```\n",
60 ),
61 );
62 };
63 ($Small:ty => $Large:ty, #[$attr:meta] $(,)?) => {
64 impl_from!(
65 $Small => $Large,
66 #[$attr],
67 concat!("Converts [`", stringify!($Small), "`] to [`", stringify!($Large), "`] losslessly."),
68 );
69 };
70 ($Small:ty => $Large:ty, #[$attr:meta], $doc:expr $(,)?) => {
71 #[$attr]
72 impl From<$Small> for $Large {
73 #[doc = $doc]
76 #[inline(always)]
77 fn from(small: $Small) -> Self {
78 small as Self
79 }
80 }
81 };
82}
83
84impl_from!(bool => u8);
86impl_from!(bool => u16);
87impl_from!(bool => u32);
88impl_from!(bool => u64);
89impl_from!(bool => u128);
90impl_from!(bool => usize);
91impl_from!(bool => i8);
92impl_from!(bool => i16);
93impl_from!(bool => i32);
94impl_from!(bool => i64);
95impl_from!(bool => i128);
96impl_from!(bool => isize);
97
98impl_from!(u8 => u16, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
100impl_from!(u8 => u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
101impl_from!(u8 => u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
102impl_from!(u8 => u128, #[stable(feature = "i128", since = "1.26.0")]);
103impl_from!(u8 => usize, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
104impl_from!(u16 => u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
105impl_from!(u16 => u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
106impl_from!(u16 => u128, #[stable(feature = "i128", since = "1.26.0")]);
107impl_from!(u32 => u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
108impl_from!(u32 => u128, #[stable(feature = "i128", since = "1.26.0")]);
109impl_from!(u64 => u128, #[stable(feature = "i128", since = "1.26.0")]);
110
111impl_from!(i8 => i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
113impl_from!(i8 => i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
114impl_from!(i8 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
115impl_from!(i8 => i128, #[stable(feature = "i128", since = "1.26.0")]);
116impl_from!(i8 => isize, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
117impl_from!(i16 => i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
118impl_from!(i16 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
119impl_from!(i16 => i128, #[stable(feature = "i128", since = "1.26.0")]);
120impl_from!(i32 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
121impl_from!(i32 => i128, #[stable(feature = "i128", since = "1.26.0")]);
122impl_from!(i64 => i128, #[stable(feature = "i128", since = "1.26.0")]);
123
124impl_from!(u8 => i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
126impl_from!(u8 => i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
127impl_from!(u8 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
128impl_from!(u8 => i128, #[stable(feature = "i128", since = "1.26.0")]);
129impl_from!(u16 => i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
130impl_from!(u16 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
131impl_from!(u16 => i128, #[stable(feature = "i128", since = "1.26.0")]);
132impl_from!(u32 => i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")]);
133impl_from!(u32 => i128, #[stable(feature = "i128", since = "1.26.0")]);
134impl_from!(u64 => i128, #[stable(feature = "i128", since = "1.26.0")]);
135
136impl_from!(u16 => usize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")]);
140impl_from!(u8 => isize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")]);
141impl_from!(i16 => isize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")]);
142
143impl_from!(i8 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
155impl_from!(i8 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
156impl_from!(i16 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
157impl_from!(i16 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
158impl_from!(i32 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
159
160impl_from!(u8 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
162impl_from!(u8 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
163impl_from!(u16 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
164impl_from!(u16 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
165impl_from!(u32 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
166
167impl_from!(f16 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
171impl_from!(f16 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
172impl_from!(f32 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
173impl_from!(f32 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
174impl_from!(f64 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
175
176macro_rules! impl_float_from_bool {
177 ($float:ty) => {
178 #[stable(feature = "float_from_bool", since = "1.68.0")]
179 impl From<bool> for $float {
180 #[doc = concat!("Converts a [`bool`] to [`", stringify!($float),"`] losslessly.")]
181 #[doc = concat!("let x: ", stringify!($float)," = false.into();")]
186 #[doc = concat!("let y: ", stringify!($float)," = true.into();")]
190 #[inline]
193 fn from(small: bool) -> Self {
194 small as u8 as Self
195 }
196 }
197 };
198}
199
200impl_float_from_bool!(f32);
202impl_float_from_bool!(f64);
203
204macro_rules! impl_try_from_unbounded {
206 ($source:ty => $($target:ty),+) => {$(
207 #[stable(feature = "try_from", since = "1.34.0")]
208 impl TryFrom<$source> for $target {
209 type Error = TryFromIntError;
210
211 #[inline]
215 fn try_from(value: $source) -> Result<Self, Self::Error> {
216 Ok(value as Self)
217 }
218 }
219 )*}
220}
221
222macro_rules! impl_try_from_lower_bounded {
224 ($source:ty => $($target:ty),+) => {$(
225 #[stable(feature = "try_from", since = "1.34.0")]
226 impl TryFrom<$source> for $target {
227 type Error = TryFromIntError;
228
229 #[inline]
233 fn try_from(u: $source) -> Result<Self, Self::Error> {
234 if u >= 0 {
235 Ok(u as Self)
236 } else {
237 Err(TryFromIntError(()))
238 }
239 }
240 }
241 )*}
242}
243
244macro_rules! impl_try_from_upper_bounded {
246 ($source:ty => $($target:ty),+) => {$(
247 #[stable(feature = "try_from", since = "1.34.0")]
248 impl TryFrom<$source> for $target {
249 type Error = TryFromIntError;
250
251 #[inline]
255 fn try_from(u: $source) -> Result<Self, Self::Error> {
256 if u > (Self::MAX as $source) {
257 Err(TryFromIntError(()))
258 } else {
259 Ok(u as Self)
260 }
261 }
262 }
263 )*}
264}
265
266macro_rules! impl_try_from_both_bounded {
268 ($source:ty => $($target:ty),+) => {$(
269 #[stable(feature = "try_from", since = "1.34.0")]
270 impl TryFrom<$source> for $target {
271 type Error = TryFromIntError;
272
273 #[inline]
277 fn try_from(u: $source) -> Result<Self, Self::Error> {
278 let min = Self::MIN as $source;
279 let max = Self::MAX as $source;
280 if u < min || u > max {
281 Err(TryFromIntError(()))
282 } else {
283 Ok(u as Self)
284 }
285 }
286 }
287 )*}
288}
289
290macro_rules! rev {
291 ($mac:ident, $source:ty => $($target:ty),+) => {$(
292 $mac!($target => $source);
293 )*}
294}
295
296impl_try_from_upper_bounded!(u16 => u8);
298impl_try_from_upper_bounded!(u32 => u8, u16);
299impl_try_from_upper_bounded!(u64 => u8, u16, u32);
300impl_try_from_upper_bounded!(u128 => u8, u16, u32, u64);
301
302impl_try_from_both_bounded!(i16 => i8);
304impl_try_from_both_bounded!(i32 => i8, i16);
305impl_try_from_both_bounded!(i64 => i8, i16, i32);
306impl_try_from_both_bounded!(i128 => i8, i16, i32, i64);
307
308impl_try_from_upper_bounded!(u8 => i8);
310impl_try_from_upper_bounded!(u16 => i8, i16);
311impl_try_from_upper_bounded!(u32 => i8, i16, i32);
312impl_try_from_upper_bounded!(u64 => i8, i16, i32, i64);
313impl_try_from_upper_bounded!(u128 => i8, i16, i32, i64, i128);
314
315impl_try_from_lower_bounded!(i8 => u8, u16, u32, u64, u128);
317impl_try_from_both_bounded!(i16 => u8);
318impl_try_from_lower_bounded!(i16 => u16, u32, u64, u128);
319impl_try_from_both_bounded!(i32 => u8, u16);
320impl_try_from_lower_bounded!(i32 => u32, u64, u128);
321impl_try_from_both_bounded!(i64 => u8, u16, u32);
322impl_try_from_lower_bounded!(i64 => u64, u128);
323impl_try_from_both_bounded!(i128 => u8, u16, u32, u64);
324impl_try_from_lower_bounded!(i128 => u128);
325
326impl_try_from_upper_bounded!(usize => isize);
328impl_try_from_lower_bounded!(isize => usize);
329
330#[cfg(target_pointer_width = "16")]
331mod ptr_try_from_impls {
332 use super::TryFromIntError;
333
334 impl_try_from_upper_bounded!(usize => u8);
335 impl_try_from_unbounded!(usize => u16, u32, u64, u128);
336 impl_try_from_upper_bounded!(usize => i8, i16);
337 impl_try_from_unbounded!(usize => i32, i64, i128);
338
339 impl_try_from_both_bounded!(isize => u8);
340 impl_try_from_lower_bounded!(isize => u16, u32, u64, u128);
341 impl_try_from_both_bounded!(isize => i8);
342 impl_try_from_unbounded!(isize => i16, i32, i64, i128);
343
344 rev!(impl_try_from_upper_bounded, usize => u32, u64, u128);
345 rev!(impl_try_from_lower_bounded, usize => i8, i16);
346 rev!(impl_try_from_both_bounded, usize => i32, i64, i128);
347
348 rev!(impl_try_from_upper_bounded, isize => u16, u32, u64, u128);
349 rev!(impl_try_from_both_bounded, isize => i32, i64, i128);
350}
351
352#[cfg(target_pointer_width = "32")]
353mod ptr_try_from_impls {
354 use super::TryFromIntError;
355
356 impl_try_from_upper_bounded!(usize => u8, u16);
357 impl_try_from_unbounded!(usize => u32, u64, u128);
358 impl_try_from_upper_bounded!(usize => i8, i16, i32);
359 impl_try_from_unbounded!(usize => i64, i128);
360
361 impl_try_from_both_bounded!(isize => u8, u16);
362 impl_try_from_lower_bounded!(isize => u32, u64, u128);
363 impl_try_from_both_bounded!(isize => i8, i16);
364 impl_try_from_unbounded!(isize => i32, i64, i128);
365
366 rev!(impl_try_from_unbounded, usize => u32);
367 rev!(impl_try_from_upper_bounded, usize => u64, u128);
368 rev!(impl_try_from_lower_bounded, usize => i8, i16, i32);
369 rev!(impl_try_from_both_bounded, usize => i64, i128);
370
371 rev!(impl_try_from_unbounded, isize => u16);
372 rev!(impl_try_from_upper_bounded, isize => u32, u64, u128);
373 rev!(impl_try_from_unbounded, isize => i32);
374 rev!(impl_try_from_both_bounded, isize => i64, i128);
375}
376
377#[cfg(target_pointer_width = "64")]
378mod ptr_try_from_impls {
379 use super::TryFromIntError;
380
381 impl_try_from_upper_bounded!(usize => u8, u16, u32);
382 impl_try_from_unbounded!(usize => u64, u128);
383 impl_try_from_upper_bounded!(usize => i8, i16, i32, i64);
384 impl_try_from_unbounded!(usize => i128);
385
386 impl_try_from_both_bounded!(isize => u8, u16, u32);
387 impl_try_from_lower_bounded!(isize => u64, u128);
388 impl_try_from_both_bounded!(isize => i8, i16, i32);
389 impl_try_from_unbounded!(isize => i64, i128);
390
391 rev!(impl_try_from_unbounded, usize => u32, u64);
392 rev!(impl_try_from_upper_bounded, usize => u128);
393 rev!(impl_try_from_lower_bounded, usize => i8, i16, i32, i64);
394 rev!(impl_try_from_both_bounded, usize => i128);
395
396 rev!(impl_try_from_unbounded, isize => u16, u32);
397 rev!(impl_try_from_upper_bounded, isize => u64, u128);
398 rev!(impl_try_from_unbounded, isize => i32, i64);
399 rev!(impl_try_from_both_bounded, isize => i128);
400}
401
402use crate::num::NonZero;
404
405macro_rules! impl_nonzero_int_from_nonzero_int {
406 ($Small:ty => $Large:ty) => {
407 #[stable(feature = "nz_int_conv", since = "1.41.0")]
408 impl From<NonZero<$Small>> for NonZero<$Large> {
409 #[doc = concat!("Converts <code>[NonZero]\\<[", stringify!($Small), "]></code> ")]
412 #[doc = concat!("to <code>[NonZero]\\<[", stringify!($Large), "]></code> losslessly.")]
413 #[inline]
414 fn from(small: NonZero<$Small>) -> Self {
415 unsafe { Self::new_unchecked(From::from(small.get())) }
417 }
418 }
419 };
420}
421
422impl_nonzero_int_from_nonzero_int!(u8 => u16);
424impl_nonzero_int_from_nonzero_int!(u8 => u32);
425impl_nonzero_int_from_nonzero_int!(u8 => u64);
426impl_nonzero_int_from_nonzero_int!(u8 => u128);
427impl_nonzero_int_from_nonzero_int!(u8 => usize);
428impl_nonzero_int_from_nonzero_int!(u16 => u32);
429impl_nonzero_int_from_nonzero_int!(u16 => u64);
430impl_nonzero_int_from_nonzero_int!(u16 => u128);
431impl_nonzero_int_from_nonzero_int!(u16 => usize);
432impl_nonzero_int_from_nonzero_int!(u32 => u64);
433impl_nonzero_int_from_nonzero_int!(u32 => u128);
434impl_nonzero_int_from_nonzero_int!(u64 => u128);
435
436impl_nonzero_int_from_nonzero_int!(i8 => i16);
438impl_nonzero_int_from_nonzero_int!(i8 => i32);
439impl_nonzero_int_from_nonzero_int!(i8 => i64);
440impl_nonzero_int_from_nonzero_int!(i8 => i128);
441impl_nonzero_int_from_nonzero_int!(i8 => isize);
442impl_nonzero_int_from_nonzero_int!(i16 => i32);
443impl_nonzero_int_from_nonzero_int!(i16 => i64);
444impl_nonzero_int_from_nonzero_int!(i16 => i128);
445impl_nonzero_int_from_nonzero_int!(i16 => isize);
446impl_nonzero_int_from_nonzero_int!(i32 => i64);
447impl_nonzero_int_from_nonzero_int!(i32 => i128);
448impl_nonzero_int_from_nonzero_int!(i64 => i128);
449
450impl_nonzero_int_from_nonzero_int!(u8 => i16);
452impl_nonzero_int_from_nonzero_int!(u8 => i32);
453impl_nonzero_int_from_nonzero_int!(u8 => i64);
454impl_nonzero_int_from_nonzero_int!(u8 => i128);
455impl_nonzero_int_from_nonzero_int!(u8 => isize);
456impl_nonzero_int_from_nonzero_int!(u16 => i32);
457impl_nonzero_int_from_nonzero_int!(u16 => i64);
458impl_nonzero_int_from_nonzero_int!(u16 => i128);
459impl_nonzero_int_from_nonzero_int!(u32 => i64);
460impl_nonzero_int_from_nonzero_int!(u32 => i128);
461impl_nonzero_int_from_nonzero_int!(u64 => i128);
462
463macro_rules! impl_nonzero_int_try_from_int {
464 ($Int:ty) => {
465 #[stable(feature = "nzint_try_from_int_conv", since = "1.46.0")]
466 impl TryFrom<$Int> for NonZero<$Int> {
467 type Error = TryFromIntError;
468
469 #[doc = concat!("Attempts to convert [`", stringify!($Int), "`] ")]
472 #[doc = concat!("to <code>[NonZero]\\<[", stringify!($Int), "]></code>.")]
473 #[inline]
474 fn try_from(value: $Int) -> Result<Self, Self::Error> {
475 Self::new(value).ok_or(TryFromIntError(()))
476 }
477 }
478 };
479}
480
481impl_nonzero_int_try_from_int!(u8);
483impl_nonzero_int_try_from_int!(u16);
484impl_nonzero_int_try_from_int!(u32);
485impl_nonzero_int_try_from_int!(u64);
486impl_nonzero_int_try_from_int!(u128);
487impl_nonzero_int_try_from_int!(usize);
488impl_nonzero_int_try_from_int!(i8);
489impl_nonzero_int_try_from_int!(i16);
490impl_nonzero_int_try_from_int!(i32);
491impl_nonzero_int_try_from_int!(i64);
492impl_nonzero_int_try_from_int!(i128);
493impl_nonzero_int_try_from_int!(isize);
494
495macro_rules! impl_nonzero_int_try_from_nonzero_int {
496 ($source:ty => $($target:ty),+) => {$(
497 #[stable(feature = "nzint_try_from_nzint_conv", since = "1.49.0")]
498 impl TryFrom<NonZero<$source>> for NonZero<$target> {
499 type Error = TryFromIntError;
500
501 #[doc = concat!("Attempts to convert <code>[NonZero]\\<[", stringify!($source), "]></code> ")]
504 #[doc = concat!("to <code>[NonZero]\\<[", stringify!($target), "]></code>.")]
505 #[inline]
506 fn try_from(value: NonZero<$source>) -> Result<Self, Self::Error> {
507 Ok(unsafe { Self::new_unchecked(<$target>::try_from(value.get())?) })
509 }
510 }
511 )*};
512}
513
514impl_nonzero_int_try_from_nonzero_int!(u16 => u8);
516impl_nonzero_int_try_from_nonzero_int!(u32 => u8, u16, usize);
517impl_nonzero_int_try_from_nonzero_int!(u64 => u8, u16, u32, usize);
518impl_nonzero_int_try_from_nonzero_int!(u128 => u8, u16, u32, u64, usize);
519impl_nonzero_int_try_from_nonzero_int!(usize => u8, u16, u32, u64, u128);
520
521impl_nonzero_int_try_from_nonzero_int!(i16 => i8);
523impl_nonzero_int_try_from_nonzero_int!(i32 => i8, i16, isize);
524impl_nonzero_int_try_from_nonzero_int!(i64 => i8, i16, i32, isize);
525impl_nonzero_int_try_from_nonzero_int!(i128 => i8, i16, i32, i64, isize);
526impl_nonzero_int_try_from_nonzero_int!(isize => i8, i16, i32, i64, i128);
527
528impl_nonzero_int_try_from_nonzero_int!(u8 => i8);
530impl_nonzero_int_try_from_nonzero_int!(u16 => i8, i16, isize);
531impl_nonzero_int_try_from_nonzero_int!(u32 => i8, i16, i32, isize);
532impl_nonzero_int_try_from_nonzero_int!(u64 => i8, i16, i32, i64, isize);
533impl_nonzero_int_try_from_nonzero_int!(u128 => i8, i16, i32, i64, i128, isize);
534impl_nonzero_int_try_from_nonzero_int!(usize => i8, i16, i32, i64, i128, isize);
535
536impl_nonzero_int_try_from_nonzero_int!(i8 => u8, u16, u32, u64, u128, usize);
538impl_nonzero_int_try_from_nonzero_int!(i16 => u8, u16, u32, u64, u128, usize);
539impl_nonzero_int_try_from_nonzero_int!(i32 => u8, u16, u32, u64, u128, usize);
540impl_nonzero_int_try_from_nonzero_int!(i64 => u8, u16, u32, u64, u128, usize);
541impl_nonzero_int_try_from_nonzero_int!(i128 => u8, u16, u32, u64, u128, usize);
542impl_nonzero_int_try_from_nonzero_int!(isize => u8, u16, u32, u64, u128, usize);