Trait std::fmt::UpperHex

1.0.0 · source ·
pub trait UpperHex {
    // Required method
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>;
}
Expand description

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;

        fmt::UpperHex::fmt(&val, f) // delegate to i32's implementation
    }
}

let l = Length(i32::MAX);

assert_eq!(format!("l as hex is: {l:X}"), "l as hex is: 7FFFFFFF");

assert_eq!(format!("l as hex is: {l:#010X}"), "l as hex is: 0x7FFFFFFF");
Run

Required Methods§

source

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

Implementors§

source§

impl UpperHex for i8

source§

impl UpperHex for i16

source§

impl UpperHex for i32

source§

impl UpperHex for i64

source§

impl UpperHex for i128

source§

impl UpperHex for isize

source§

impl UpperHex for u8

source§

impl UpperHex for u16

source§

impl UpperHex for u32

source§

impl UpperHex for u64

source§

impl UpperHex for u128

source§

impl UpperHex for usize

source§

impl<T> UpperHex for &T
where T: UpperHex + ?Sized,

source§

impl<T> UpperHex for &mut T
where T: UpperHex + ?Sized,

1.28.0 · source§

impl<T> UpperHex for NonZero<T>

1.74.0 · source§

impl<T> UpperHex for Saturating<T>
where T: UpperHex,

1.11.0 · source§

impl<T> UpperHex for Wrapping<T>
where T: UpperHex,