Trait CastTo

Source

pub trait CastTo<T, R: Rounding>: Sized {
    type Error: Into<R::MaximumError> + Error;

    // Required methods
    fn try_cast_to(self, mode: R) -> Result<T, Self::Error>;
    fn cast_to(self, mode: R) -> T;
}

Expand description

Generic “into” conversion trait with specified rounding mode

This trait supports Into- and TryInto-like conversions, but with a specified rounding mode:

Conversions may be fallible, like TryInto.
Conversions may be lossy, according to the Rounding mode used.
Conversions must be value-preserving, like Into. For example, -1_i8 and -1_i32 are conceptually the same value while 255_u8 is conceptually a different value.

The Rounding mode must be specified:

let x: i32 = 3.14192.cast_to(Floor);
assert_eq!(x, 3);

let y = (1i32 << 30) - 1;
let z: f32 = y.cast_to(Nearest);  // this example rounds up
assert_eq!(z as i32, 1i32 << 30);