Trait alloc::fmt::Binary 1.0.0[−][src]
Expand description
b
formatting.
The Binary
trait should format its output as a number in binary.
For primitive signed integers (i8
to i128
, and isize
),
negative values are formatted as the two’s complement representation.
The alternate flag, #
, adds a 0b
in front of the output.
For more information on formatters, see the module-level documentation.
Examples
Basic usage with i32
:
let x = 42; // 42 is '101010' in binary
assert_eq!(format!("{:b}", x), "101010");
assert_eq!(format!("{:#b}", x), "0b101010");
assert_eq!(format!("{:b}", -16), "11111111111111111111111111110000");
RunImplementing Binary
on a type:
use std::fmt;
struct Length(i32);
impl fmt::Binary for Length {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let val = self.0;
fmt::Binary::fmt(&val, f) // delegate to i32's implementation
}
}
let l = Length(107);
assert_eq!(format!("l as binary is: {:b}", l), "l as binary is: 1101011");
assert_eq!(
format!("l as binary is: {:#032b}", l),
"l as binary is: 0b000000000000000000000001101011"
);
Run