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

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

`e` formatting.

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 `f64`:

    let x = 42.0; // 42.0 is '4.2e1' in scientific notation

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

Implementing `LowerExp` on a type:

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

Formats the value using the given formatter.

Loading content...

## Implementors

### `impl LowerExp for f32`[src]

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

### `impl LowerExp for f64`[src]

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

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

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

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

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

Loading content...

# 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`)