Line data    Source code

       1              : //! `u64`` and `usize`` aren't guaranteed to be identical in Rust, but life is much simpler if that's the case.
       2              : 
       3              : pub(crate) const _ASSERT_U64_EQ_USIZE: () = {
       4              :     if std::mem::size_of::<usize>() != std::mem::size_of::<u64>() {
       5              :         panic!(
       6              :             "the traits defined in this module assume that usize and u64 can be converted to each other without loss of information"
       7              :         );
       8              :     }
       9              : };
      10              : 
      11              : pub(crate) trait U64IsUsize {
      12              :     fn into_usize(self) -> usize;
      13              : }
      14              : 
      15              : impl U64IsUsize for u64 {
      16              :     #[inline(always)]
      17     16786551 :     fn into_usize(self) -> usize {
      18     16786551 :         #[allow(clippy::let_unit_value)]
      19     16786551 :         let _ = _ASSERT_U64_EQ_USIZE;
      20     16786551 :         self as usize
      21     16786551 :     }
      22              : }
      23              : 
      24              : pub(crate) trait UsizeIsU64 {
      25              :     fn into_u64(self) -> u64;
      26              : }
      27              : 
      28              : impl UsizeIsU64 for usize {
      29              :     #[inline(always)]
      30     39199348 :     fn into_u64(self) -> u64 {
      31     39199348 :         #[allow(clippy::let_unit_value)]
      32     39199348 :         let _ = _ASSERT_U64_EQ_USIZE;
      33     39199348 :         self as u64
      34     39199348 :     }
      35              : }
      36              : 
      37          488 : pub const fn u64_to_usize(x: u64) -> usize {
      38          488 :     #[allow(clippy::let_unit_value)]
      39          488 :     let _ = _ASSERT_U64_EQ_USIZE;
      40          488 :     x as usize
      41          488 : }