Trait std::fmt::LowerHex [−] [src]

pub trait LowerHex {
    fn fmt(&self, &mut Formatter) -> Result<(), Error>;
}

Format trait for the x character.

The LowerHex trait should format its output as a number in hexadecimal, with a through f in lower case.

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:

fn main() { let x = 42; // 42 is '2a' in hex assert_eq!(format!("{:x}", x), "2a"); assert_eq!(format!("{:#x}", x), "0x2a"); }
let x = 42; // 42 is '2a' in hex

assert_eq!(format!("{:x}", x), "2a");
assert_eq!(format!("{:#x}", x), "0x2a");

Implementing LowerHex on a type:

fn main() { use std::fmt; struct Length(i32); impl fmt::LowerHex 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); }
use std::fmt;

struct Length(i32);

impl fmt::LowerHex 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);

Required Methods

fn fmt(&self, &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

Implementors