1.0.0[−][src]Trait core::fmt::UpperHex
X
formatting.
The UpperHex
trait should format its output as a number in hexadecimal, with A
through F
in upper case.
For primitive signed integers (i8
to i128
, and isize
),
negative values are formatted as the two’s complement representation.
The alternate flag, #
, adds a 0x
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 '2A' in hex assert_eq!(format!("{:X}", x), "2A"); assert_eq!(format!("{:#X}", x), "0x2A"); assert_eq!(format!("{:X}", -16), "FFFFFFF0");Run
Implementing UpperHex
on a type:
use std::fmt; struct Length(i32); impl fmt::UpperHex for Length { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { let val = self.0; write!(f, "{:X}", val) // delegate to i32's implementation } } let l = Length(9); println!("l as hex is: {:X}", l);Run