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Trait std::fmt::LowerHex

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

x formatting.

The LowerHex trait should format its output as a number in hexadecimal, with a through f in lower 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");

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;

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

let l = Length(9);

assert_eq!(format!("l as hex is: {:x}", l), "l as hex is: 9");

assert_eq!(format!("l as hex is: {:#010x}", l), "l as hex is: 0x00000009");

Required methods

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

Formats the value using the given formatter.

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Implementors

impl LowerHex for i8[src]

impl LowerHex for i16[src]

impl LowerHex for i32[src]

impl LowerHex for i64[src]

impl LowerHex for i128[src]

impl LowerHex for isize[src]

impl LowerHex for u8[src]

impl LowerHex for u16[src]

impl LowerHex for u32[src]

impl LowerHex for u64[src]

impl LowerHex for u128[src]

impl LowerHex for usize[src]

impl LowerHex for NonZeroI8[src]

impl LowerHex for NonZeroI16[src]

impl LowerHex for NonZeroI32[src]

impl LowerHex for NonZeroI64[src]

impl LowerHex for NonZeroI128[src]

impl LowerHex for NonZeroIsize[src]

impl LowerHex for NonZeroU8[src]

impl LowerHex for NonZeroU16[src]

impl LowerHex for NonZeroU32[src]

impl LowerHex for NonZeroU64[src]

impl LowerHex for NonZeroU128[src]

impl LowerHex for NonZeroUsize[src]

impl<'_, T> LowerHex for &'_ T where
    T: LowerHex + ?Sized
[src]

impl<'_, T> LowerHex for &'_ mut T where
    T: LowerHex + ?Sized
[src]

impl<T> LowerHex for Wrapping<T> where
    T: LowerHex
[src]

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© 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