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

# Trait alloc::fmt::Octal 1.0.0[−][src]

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

`o` formatting.

The `Octal` trait should format its output as a number in base-8.

For primitive signed integers (`i8` to `i128`, and `isize`), negative values are formatted as the two’s complement representation.

The alternate flag, `#`, adds a `0o` 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 '52' in octal

    assert_eq!(format!("{:o}", x), "52");
    assert_eq!(format!("{:#o}", x), "0o52");

    assert_eq!(format!("{:o}", -16), "37777777760");

Implementing `Octal` on a type:

    use std::fmt;

    struct Length(i32);

    impl fmt::Octal for Length {
        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
            let val = self.0;

            write!(f, "{:o}", val) // delegate to i32's implementation
        }
    }

    let l = Length(9);

    println!("l as octal is: {:o}", l);

## Required Methods

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

Formats the value using the given formatter.

## Implementations on Foreign Types

###

`impl Octal for NonZeroU16`

[src]

####

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

[src]

###

`impl Octal for NonZeroU32`

[src]

####

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

[src]

###

`impl Octal for NonZeroU64`

[src]

####

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

[src]

###

`impl<T> Octal for Wrapping<T> where T: Octal,`

[src]

####

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

[src]

###

`impl Octal for NonZeroU128`

[src]

####

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

[src]

###

`impl Octal for NonZeroUsize`

[src]

####

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

[src]

###

`impl Octal for NonZeroU8`

[src]

####

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

[src]

## Implementors

- `impl Octal for isize` | [src]

- `impl Octal for u8` | [src]

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

- `impl Octal for i128` | [src]

- `impl Octal for i16` | [src]

- `impl Octal for u64` | [src]

- `impl Octal for i32` | [src]

- `impl Octal for u128` | [src]

- `impl Octal for u32` | [src]

- `impl Octal for usize` | [src]

- `impl Octal for i8` | [src]

- `impl Octal for i64` | [src]

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

- `impl Octal for u16` | [src]

# Help

## Keyboard Shortcuts

`?`
  Show this help dialog
`S`
  Focus the search field
`↑`
  Move up in search results
`↓`
  Move down in search results
`↹`
  Switch tab
`⏎`
  Go to active search result
`+`
  Expand all sections
`-`
  Collapse all sections

## Search Tricks

Prefix searches with a type followed by a colon (e.g. `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g. `vec -> usize` or `* -> vec`)

Search multiple things at once by splitting your query with comma (e.g. `str,u8` or `String,struct:Vec,test`)