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.
Basic usage with i32
:
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:
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);
impl<T> LowerHex for Wrapping<T> where T: LowerHex
impl LowerHex for isize
impl LowerHex for usize
impl LowerHex for i8
impl LowerHex for u8
impl LowerHex for i16
impl LowerHex for u16
impl LowerHex for i32
impl LowerHex for u32
impl LowerHex for i64
impl LowerHex for u64
impl LowerHex for i128
impl LowerHex for u128
impl<'a, T> LowerHex for &'a T where T: LowerHex + ?Sized
impl<'a, T> LowerHex for &'a mut T where T: LowerHex + ?Sized
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/fmt/trait.LowerHex.html