Trait collections::fmt::LowerExp [−] [src]

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

Format trait for the e character.

The LowerExp trait should format its output in scientific notation with a lower-case e.

For more information on formatters, see the module-level documentation.

Examples

Basic usage with i32:

fn main() { let x = 42.0; // 42.0 is '4.2e1' in scientific notation assert_eq!(format!("{:e}", x), "4.2e1"); }
let x = 42.0; // 42.0 is '4.2e1' in scientific notation

assert_eq!(format!("{:e}", x), "4.2e1");

Implementing LowerExp on a type:

fn main() { use std::fmt; struct Length(i32); impl fmt::LowerExp for Length { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { let val = self.0; write!(f, "{}e1", val / 10) } } let l = Length(100); println!("l in scientific notation is: {:e}", l); }
use std::fmt;

struct Length(i32);

impl fmt::LowerExp for Length {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        let val = self.0;
        write!(f, "{}e1", val / 10)
    }
}

let l = Length(100);

println!("l in scientific notation is: {:e}", l);

Required Methods

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

Formats the value using the given formatter.

Implementors