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Trait std::fmt::Octal

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.

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");

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

Formats the value using the given formatter.

Implementors

© 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.Octal.html