src/libcore/convert/num.rs

   1 use super::{From, TryFrom};
   2 use crate::num::TryFromIntError;
   3
   4 mod private {
   5     /// This trait being unreachable from outside the crate
   6     /// prevents other implementations of the `FloatToInt` trait,
   7     /// which allows potentially adding more trait methods after the trait is `#[stable]`.
   8     #[unstable(feature = "convert_float_to_int", issue = "67057")]
   9     pub trait Sealed {}
  10 }
  11
  12 /// Supporting trait for inherent methods of `f32` and `f64` such as `round_unchecked_to`.
  13 /// Typically doesn’t need to be used directly.
  14 #[unstable(feature = "convert_float_to_int", issue = "67057")]
  15 pub trait FloatToInt<Int>: private::Sealed + Sized {
  16     #[cfg(not(bootstrap))]
  17     #[unstable(feature = "float_approx_unchecked_to", issue = "67058")]
  18     #[doc(hidden)]
  19     unsafe fn approx_unchecked(self) -> Int;
  20 }
  21
  22 macro_rules! impl_float_to_int {
  23     ( $Float: ident => $( $Int: ident )+ ) => {
  24         #[unstable(feature = "convert_float_to_int", issue = "67057")]
  25         impl private::Sealed for $Float {}
  26         $(
  27             #[unstable(feature = "convert_float_to_int", issue = "67057")]
  28             impl FloatToInt<$Int> for $Float {
  29                 #[cfg(not(bootstrap))]
  30                 #[doc(hidden)]
  31                 #[inline]
  32                 unsafe fn approx_unchecked(self) -> $Int {
  33                     crate::intrinsics::float_to_int_approx_unchecked(self)
  34                 }
  35             }
  36         )+
  37     }
  38 }
  39
  40 impl_float_to_int!(f32 => u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize);
  41 impl_float_to_int!(f64 => u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize);
  42
  43 // Conversion traits for primitive integer and float types
  44 // Conversions T -> T are covered by a blanket impl and therefore excluded
  45 // Some conversions from and to usize/isize are not implemented due to portability concerns
  46 macro_rules! impl_from {
  47     ($Small: ty, $Large: ty, #[$attr:meta], $doc: expr) => {
  48         #[$attr]
  49         #[doc = $doc]
  50         impl From<$Small> for $Large {
  51             #[inline]
  52             fn from(small: $Small) -> $Large {
  53                 small as $Large
  54             }
  55         }
  56     };
  57     ($Small: ty, $Large: ty, #[$attr:meta]) => {
  58         impl_from!($Small,
  59                    $Large,
  60                    #[$attr],
  61                    concat!("Converts `",
  62                            stringify!($Small),
  63                            "` to `",
  64                            stringify!($Large),
  65                            "` losslessly."));
  66     }
  67 }
  68
  69 macro_rules! impl_from_bool {
  70     ($target: ty, #[$attr:meta]) => {
  71         impl_from!(bool, $target, #[$attr], concat!("Converts a `bool` to a `",
  72             stringify!($target), "`. The resulting value is `0` for `false` and `1` for `true`
  73 values.
  74
  75 # Examples
  76
  77 ```
  78 assert_eq!(", stringify!($target), "::from(true), 1);
  79 assert_eq!(", stringify!($target), "::from(false), 0);
  80 ```"));
  81     };
  82 }
  83
  84 // Bool -> Any
  85 impl_from_bool! { u8, #[stable(feature = "from_bool", since = "1.28.0")] }
  86 impl_from_bool! { u16, #[stable(feature = "from_bool", since = "1.28.0")] }
  87 impl_from_bool! { u32, #[stable(feature = "from_bool", since = "1.28.0")] }
  88 impl_from_bool! { u64, #[stable(feature = "from_bool", since = "1.28.0")] }
  89 impl_from_bool! { u128, #[stable(feature = "from_bool", since = "1.28.0")] }
  90 impl_from_bool! { usize, #[stable(feature = "from_bool", since = "1.28.0")] }
  91 impl_from_bool! { i8, #[stable(feature = "from_bool", since = "1.28.0")] }
  92 impl_from_bool! { i16, #[stable(feature = "from_bool", since = "1.28.0")] }
  93 impl_from_bool! { i32, #[stable(feature = "from_bool", since = "1.28.0")] }
  94 impl_from_bool! { i64, #[stable(feature = "from_bool", since = "1.28.0")] }
  95 impl_from_bool! { i128, #[stable(feature = "from_bool", since = "1.28.0")] }
  96 impl_from_bool! { isize, #[stable(feature = "from_bool", since = "1.28.0")] }
  97
  98 // Unsigned -> Unsigned
  99 impl_from! { u8, u16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 100 impl_from! { u8, u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 101 impl_from! { u8, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 102 impl_from! { u8, u128, #[stable(feature = "i128", since = "1.26.0")] }
 103 impl_from! { u8, usize, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 104 impl_from! { u16, u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 105 impl_from! { u16, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 106 impl_from! { u16, u128, #[stable(feature = "i128", since = "1.26.0")] }
 107 impl_from! { u32, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 108 impl_from! { u32, u128, #[stable(feature = "i128", since = "1.26.0")] }
 109 impl_from! { u64, u128, #[stable(feature = "i128", since = "1.26.0")] }
 110
 111 // Signed -> Signed
 112 impl_from! { i8, i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 113 impl_from! { i8, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 114 impl_from! { i8, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 115 impl_from! { i8, i128, #[stable(feature = "i128", since = "1.26.0")] }
 116 impl_from! { i8, isize, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 117 impl_from! { i16, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 118 impl_from! { i16, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 119 impl_from! { i16, i128, #[stable(feature = "i128", since = "1.26.0")] }
 120 impl_from! { i32, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 121 impl_from! { i32, i128, #[stable(feature = "i128", since = "1.26.0")] }
 122 impl_from! { i64, i128, #[stable(feature = "i128", since = "1.26.0")] }
 123
 124 // Unsigned -> Signed
 125 impl_from! { u8, i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 126 impl_from! { u8, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 127 impl_from! { u8, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 128 impl_from! { u8, i128, #[stable(feature = "i128", since = "1.26.0")] }
 129 impl_from! { u16, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 130 impl_from! { u16, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 131 impl_from! { u16, i128, #[stable(feature = "i128", since = "1.26.0")] }
 132 impl_from! { u32, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 133 impl_from! { u32, i128, #[stable(feature = "i128", since = "1.26.0")] }
 134 impl_from! { u64, i128, #[stable(feature = "i128", since = "1.26.0")] }
 135
 136 // The C99 standard defines bounds on INTPTR_MIN, INTPTR_MAX, and UINTPTR_MAX
 137 // which imply that pointer-sized integers must be at least 16 bits:
 138 // https://port70.net/~nsz/c/c99/n1256.html#7.18.2.4
 139 impl_from! { u16, usize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")] }
 140 impl_from! { u8, isize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")] }
 141 impl_from! { i16, isize, #[stable(feature = "lossless_iusize_conv", since = "1.26.0")] }
 142
 143 // RISC-V defines the possibility of a 128-bit address space (RV128).
 144
 145 // CHERI proposes 256-bit “capabilities”. Unclear if this would be relevant to usize/isize.
 146 // https://www.cl.cam.ac.uk/research/security/ctsrd/pdfs/20171017a-cheri-poster.pdf
 147 // http://www.csl.sri.com/users/neumann/2012resolve-cheri.pdf
 148
 149 // Note: integers can only be represented with full precision in a float if
 150 // they fit in the significand, which is 24 bits in f32 and 53 bits in f64.
 151 // Lossy float conversions are not implemented at this time.
 152
 153 // Signed -> Float
 154 impl_from! { i8, f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 155 impl_from! { i8, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 156 impl_from! { i16, f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 157 impl_from! { i16, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 158 impl_from! { i32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 159
 160 // Unsigned -> Float
 161 impl_from! { u8, f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 162 impl_from! { u8, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 163 impl_from! { u16, f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 164 impl_from! { u16, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 165 impl_from! { u32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 166
 167 // Float -> Float
 168 impl_from! { f32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] }
 169
 170 // no possible bounds violation
 171 macro_rules! try_from_unbounded {
 172     ($source:ty, $($target:ty),*) => {$(
 173         #[stable(feature = "try_from", since = "1.34.0")]
 174         impl TryFrom<$source> for $target {
 175             type Error = TryFromIntError;
 176
 177             /// Try to create the target number type from a source
 178             /// number type. This returns an error if the source value
 179             /// is outside of the range of the target type.
 180             #[inline]
 181             fn try_from(value: $source) -> Result<Self, Self::Error> {
 182                 Ok(value as $target)
 183             }
 184         }
 185     )*}
 186 }
 187
 188 // only negative bounds
 189 macro_rules! try_from_lower_bounded {
 190     ($source:ty, $($target:ty),*) => {$(
 191         #[stable(feature = "try_from", since = "1.34.0")]
 192         impl TryFrom<$source> for $target {
 193             type Error = TryFromIntError;
 194
 195             /// Try to create the target number type from a source
 196             /// number type. This returns an error if the source value
 197             /// is outside of the range of the target type.
 198             #[inline]
 199             fn try_from(u: $source) -> Result<$target, TryFromIntError> {
 200                 if u >= 0 {
 201                     Ok(u as $target)
 202                 } else {
 203                     Err(TryFromIntError(()))
 204                 }
 205             }
 206         }
 207     )*}
 208 }
 209
 210 // unsigned to signed (only positive bound)
 211 macro_rules! try_from_upper_bounded {
 212     ($source:ty, $($target:ty),*) => {$(
 213         #[stable(feature = "try_from", since = "1.34.0")]
 214         impl TryFrom<$source> for $target {
 215             type Error = TryFromIntError;
 216
 217             /// Try to create the target number type from a source
 218             /// number type. This returns an error if the source value
 219             /// is outside of the range of the target type.
 220             #[inline]
 221             fn try_from(u: $source) -> Result<$target, TryFromIntError> {
 222                 if u > (<$target>::max_value() as $source) {
 223                     Err(TryFromIntError(()))
 224                 } else {
 225                     Ok(u as $target)
 226                 }
 227             }
 228         }
 229     )*}
 230 }
 231
 232 // all other cases
 233 macro_rules! try_from_both_bounded {
 234     ($source:ty, $($target:ty),*) => {$(
 235         #[stable(feature = "try_from", since = "1.34.0")]
 236         impl TryFrom<$source> for $target {
 237             type Error = TryFromIntError;
 238
 239             /// Try to create the target number type from a source
 240             /// number type. This returns an error if the source value
 241             /// is outside of the range of the target type.
 242             #[inline]
 243             fn try_from(u: $source) -> Result<$target, TryFromIntError> {
 244                 let min = <$target>::min_value() as $source;
 245                 let max = <$target>::max_value() as $source;
 246                 if u < min || u > max {
 247                     Err(TryFromIntError(()))
 248                 } else {
 249                     Ok(u as $target)
 250                 }
 251             }
 252         }
 253     )*}
 254 }
 255
 256 macro_rules! rev {
 257     ($mac:ident, $source:ty, $($target:ty),*) => {$(
 258         $mac!($target, $source);
 259     )*}
 260 }
 261
 262 // intra-sign conversions
 263 try_from_upper_bounded!(u16, u8);
 264 try_from_upper_bounded!(u32, u16, u8);
 265 try_from_upper_bounded!(u64, u32, u16, u8);
 266 try_from_upper_bounded!(u128, u64, u32, u16, u8);
 267
 268 try_from_both_bounded!(i16, i8);
 269 try_from_both_bounded!(i32, i16, i8);
 270 try_from_both_bounded!(i64, i32, i16, i8);
 271 try_from_both_bounded!(i128, i64, i32, i16, i8);
 272
 273 // unsigned-to-signed
 274 try_from_upper_bounded!(u8, i8);
 275 try_from_upper_bounded!(u16, i8, i16);
 276 try_from_upper_bounded!(u32, i8, i16, i32);
 277 try_from_upper_bounded!(u64, i8, i16, i32, i64);
 278 try_from_upper_bounded!(u128, i8, i16, i32, i64, i128);
 279
 280 // signed-to-unsigned
 281 try_from_lower_bounded!(i8, u8, u16, u32, u64, u128);
 282 try_from_lower_bounded!(i16, u16, u32, u64, u128);
 283 try_from_lower_bounded!(i32, u32, u64, u128);
 284 try_from_lower_bounded!(i64, u64, u128);
 285 try_from_lower_bounded!(i128, u128);
 286 try_from_both_bounded!(i16, u8);
 287 try_from_both_bounded!(i32, u16, u8);
 288 try_from_both_bounded!(i64, u32, u16, u8);
 289 try_from_both_bounded!(i128, u64, u32, u16, u8);
 290
 291 // usize/isize
 292 try_from_upper_bounded!(usize, isize);
 293 try_from_lower_bounded!(isize, usize);
 294
 295 #[cfg(target_pointer_width = "16")]
 296 mod ptr_try_from_impls {
 297     use super::TryFromIntError;
 298     use crate::convert::TryFrom;
 299
 300     try_from_upper_bounded!(usize, u8);
 301     try_from_unbounded!(usize, u16, u32, u64, u128);
 302     try_from_upper_bounded!(usize, i8, i16);
 303     try_from_unbounded!(usize, i32, i64, i128);
 304
 305     try_from_both_bounded!(isize, u8);
 306     try_from_lower_bounded!(isize, u16, u32, u64, u128);
 307     try_from_both_bounded!(isize, i8);
 308     try_from_unbounded!(isize, i16, i32, i64, i128);
 309
 310     rev!(try_from_upper_bounded, usize, u32, u64, u128);
 311     rev!(try_from_lower_bounded, usize, i8, i16);
 312     rev!(try_from_both_bounded, usize, i32, i64, i128);
 313
 314     rev!(try_from_upper_bounded, isize, u16, u32, u64, u128);
 315     rev!(try_from_both_bounded, isize, i32, i64, i128);
 316 }
 317
 318 #[cfg(target_pointer_width = "32")]
 319 mod ptr_try_from_impls {
 320     use super::TryFromIntError;
 321     use crate::convert::TryFrom;
 322
 323     try_from_upper_bounded!(usize, u8, u16);
 324     try_from_unbounded!(usize, u32, u64, u128);
 325     try_from_upper_bounded!(usize, i8, i16, i32);
 326     try_from_unbounded!(usize, i64, i128);
 327
 328     try_from_both_bounded!(isize, u8, u16);
 329     try_from_lower_bounded!(isize, u32, u64, u128);
 330     try_from_both_bounded!(isize, i8, i16);
 331     try_from_unbounded!(isize, i32, i64, i128);
 332
 333     rev!(try_from_unbounded, usize, u32);
 334     rev!(try_from_upper_bounded, usize, u64, u128);
 335     rev!(try_from_lower_bounded, usize, i8, i16, i32);
 336     rev!(try_from_both_bounded, usize, i64, i128);
 337
 338     rev!(try_from_unbounded, isize, u16);
 339     rev!(try_from_upper_bounded, isize, u32, u64, u128);
 340     rev!(try_from_unbounded, isize, i32);
 341     rev!(try_from_both_bounded, isize, i64, i128);
 342 }
 343
 344 #[cfg(target_pointer_width = "64")]
 345 mod ptr_try_from_impls {
 346     use super::TryFromIntError;
 347     use crate::convert::TryFrom;
 348
 349     try_from_upper_bounded!(usize, u8, u16, u32);
 350     try_from_unbounded!(usize, u64, u128);
 351     try_from_upper_bounded!(usize, i8, i16, i32, i64);
 352     try_from_unbounded!(usize, i128);
 353
 354     try_from_both_bounded!(isize, u8, u16, u32);
 355     try_from_lower_bounded!(isize, u64, u128);
 356     try_from_both_bounded!(isize, i8, i16, i32);
 357     try_from_unbounded!(isize, i64, i128);
 358
 359     rev!(try_from_unbounded, usize, u32, u64);
 360     rev!(try_from_upper_bounded, usize, u128);
 361     rev!(try_from_lower_bounded, usize, i8, i16, i32, i64);
 362     rev!(try_from_both_bounded, usize, i128);
 363
 364     rev!(try_from_unbounded, isize, u16, u32);
 365     rev!(try_from_upper_bounded, isize, u64, u128);
 366     rev!(try_from_unbounded, isize, i32, i64);
 367     rev!(try_from_both_bounded, isize, i128);
 368 }
 369
 370 // Conversion traits for non-zero integer types
 371 use crate::num::NonZeroI128;
 372 use crate::num::NonZeroI16;
 373 use crate::num::NonZeroI32;
 374 use crate::num::NonZeroI64;
 375 use crate::num::NonZeroI8;
 376 use crate::num::NonZeroIsize;
 377 use crate::num::NonZeroU128;
 378 use crate::num::NonZeroU16;
 379 use crate::num::NonZeroU32;
 380 use crate::num::NonZeroU64;
 381 use crate::num::NonZeroU8;
 382 use crate::num::NonZeroUsize;
 383
 384 macro_rules! nzint_impl_from {
 385     ($Small: ty, $Large: ty, #[$attr:meta], $doc: expr) => {
 386         #[$attr]
 387         #[doc = $doc]
 388         impl From<$Small> for $Large {
 389             #[inline]
 390             fn from(small: $Small) -> $Large {
 391                 // SAFETY: input type guarantees the value is non-zero
 392                 unsafe {
 393                     <$Large>::new_unchecked(small.get().into())
 394                 }
 395             }
 396         }
 397     };
 398     ($Small: ty, $Large: ty, #[$attr:meta]) => {
 399         nzint_impl_from!($Small,
 400                    $Large,
 401                    #[$attr],
 402                    concat!("Converts `",
 403                            stringify!($Small),
 404                            "` to `",
 405                            stringify!($Large),
 406                            "` losslessly."));
 407     }
 408 }
 409
 410 // Non-zero Unsigned -> Non-zero Unsigned
 411 nzint_impl_from! { NonZeroU8, NonZeroU16, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 412 nzint_impl_from! { NonZeroU8, NonZeroU32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 413 nzint_impl_from! { NonZeroU8, NonZeroU64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 414 nzint_impl_from! { NonZeroU8, NonZeroU128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 415 nzint_impl_from! { NonZeroU8, NonZeroUsize, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 416 nzint_impl_from! { NonZeroU16, NonZeroU32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 417 nzint_impl_from! { NonZeroU16, NonZeroU64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 418 nzint_impl_from! { NonZeroU16, NonZeroU128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 419 nzint_impl_from! { NonZeroU16, NonZeroUsize, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 420 nzint_impl_from! { NonZeroU32, NonZeroU64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 421 nzint_impl_from! { NonZeroU32, NonZeroU128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 422 nzint_impl_from! { NonZeroU64, NonZeroU128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 423
 424 // Non-zero Signed -> Non-zero Signed
 425 nzint_impl_from! { NonZeroI8, NonZeroI16, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 426 nzint_impl_from! { NonZeroI8, NonZeroI32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 427 nzint_impl_from! { NonZeroI8, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 428 nzint_impl_from! { NonZeroI8, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 429 nzint_impl_from! { NonZeroI8, NonZeroIsize, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 430 nzint_impl_from! { NonZeroI16, NonZeroI32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 431 nzint_impl_from! { NonZeroI16, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 432 nzint_impl_from! { NonZeroI16, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 433 nzint_impl_from! { NonZeroI16, NonZeroIsize, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 434 nzint_impl_from! { NonZeroI32, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 435 nzint_impl_from! { NonZeroI32, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 436 nzint_impl_from! { NonZeroI64, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 437
 438 // NonZero UnSigned -> Non-zero Signed
 439 nzint_impl_from! { NonZeroU8, NonZeroI16, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 440 nzint_impl_from! { NonZeroU8, NonZeroI32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 441 nzint_impl_from! { NonZeroU8, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 442 nzint_impl_from! { NonZeroU8, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 443 nzint_impl_from! { NonZeroU8, NonZeroIsize, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 444 nzint_impl_from! { NonZeroU16, NonZeroI32, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 445 nzint_impl_from! { NonZeroU16, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 446 nzint_impl_from! { NonZeroU16, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 447 nzint_impl_from! { NonZeroU32, NonZeroI64, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 448 nzint_impl_from! { NonZeroU32, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }
 449 nzint_impl_from! { NonZeroU64, NonZeroI128, #[stable(feature = "nz_int_conv", since = "1.41.0")] }