tests/ui/consts/const-int-pow-rpass.rs

   1 // run-pass
   2
   3 #![feature(wrapping_next_power_of_two)]
   4
   5 const IS_POWER_OF_TWO_A: bool = 0u32.is_power_of_two();
   6 const IS_POWER_OF_TWO_B: bool = 32u32.is_power_of_two();
   7 const IS_POWER_OF_TWO_C: bool = 33u32.is_power_of_two();
   8
   9 const POW: u8 = 3u8.pow(5);
  10
  11 const CHECKED_POW_OK: Option<u8> = 3u8.checked_pow(5);
  12 const CHECKED_POW_OVERFLOW: Option<u8> = 3u8.checked_pow(6);
  13
  14 const WRAPPING_POW: u8 = 3u8.wrapping_pow(6);
  15 const OVERFLOWING_POW: (u8, bool) = 3u8.overflowing_pow(6);
  16 const SATURATING_POW: u8 = 3u8.saturating_pow(6);
  17
  18 const NEXT_POWER_OF_TWO: u32 = 3u32.next_power_of_two();
  19
  20 const CHECKED_NEXT_POWER_OF_TWO_OK: Option<u32> = 3u32.checked_next_power_of_two();
  21 const CHECKED_NEXT_POWER_OF_TWO_OVERFLOW: Option<u32> =
  22     u32::MAX.checked_next_power_of_two();
  23
  24 const WRAPPING_NEXT_POWER_OF_TWO: u32 =
  25     u32::MAX.wrapping_next_power_of_two();
  26
  27 fn main() {
  28     assert!(!IS_POWER_OF_TWO_A);
  29     assert!(IS_POWER_OF_TWO_B);
  30     assert!(!IS_POWER_OF_TWO_C);
  31
  32     assert_eq!(POW, 243);
  33
  34     assert_eq!(CHECKED_POW_OK, Some(243));
  35     assert_eq!(CHECKED_POW_OVERFLOW, None);
  36
  37     assert_eq!(WRAPPING_POW, 217);
  38     assert_eq!(OVERFLOWING_POW, (217, true));
  39     assert_eq!(SATURATING_POW, u8::MAX);
  40
  41     assert_eq!(NEXT_POWER_OF_TWO, 4);
  42
  43     assert_eq!(CHECKED_NEXT_POWER_OF_TWO_OK, Some(4));
  44     assert_eq!(CHECKED_NEXT_POWER_OF_TWO_OVERFLOW, None);
  45
  46     assert_eq!(WRAPPING_NEXT_POWER_OF_TWO, 0);
  47 }