std::fmt::UpperHex - Rust
Description: API documentation for the Rust `UpperHex` trait in crate `std`.
Keywords: rust, rustlang, rust-lang, UpperHex

# Trait std::fmt::UpperHex 1.0.0[−][src]

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

`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

## Required Methods

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

Formats the value using the given formatter.

## Implementors

- `impl UpperHex for u8` | [src]

- `impl<'a, T> UpperHex for &'a T where T: UpperHex + ?Sized,` | [src]

- `impl UpperHex for u32` | [src]

- `impl<T> UpperHex for Wrapping<T> where T: UpperHex,` | [src]

- `impl UpperHex for u128` | [src]

- `impl UpperHex for i128` | [src]

- `impl UpperHex for NonZeroU8` | [src]

- `impl UpperHex for i64` | [src]

- `impl UpperHex for u16` | [src]

- `impl UpperHex for NonZeroUsize` | [src]

- `impl<'a, T> UpperHex for &'a mut T where T: UpperHex + ?Sized,` | [src]

- `impl UpperHex for u64` | [src]

- `impl UpperHex for i32` | [src]

- `impl UpperHex for i16` | [src]

- `impl UpperHex for isize` | [src]

- `impl UpperHex for NonZeroU32` | [src]

- `impl UpperHex for NonZeroU64` | [src]

- `impl UpperHex for i8` | [src]

- `impl UpperHex for NonZeroU16` | [src]

- `impl UpperHex for NonZeroU128` | [src]

- `impl UpperHex for usize` | [src]

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