# Trait num_traits::identities::One [−] [src]

    pub trait One: Sized + Mul<Self, Output = Self> {
        fn one() -> Self;
    }

Defines a multiplicative identity element for `Self`.

## Required Methods

### `fn one() -> Self`

Returns the multiplicative identity element of `Self`, `1`.

# Laws

    a * 1 = a       ∀ a ∈ Self
    1 * a = a       ∀ a ∈ Self

# Purity

This function should return the same result at all times regardless of external mutable state, for example values stored in TLS or in `static mut`s.

## Implementors

- `impl One for usize`
- `impl One for u8`
- `impl One for u16`
- `impl One for u32`
- `impl One for u64`
- `impl One for isize`
- `impl One for i8`
- `impl One for i16`
- `impl One for i32`
- `impl One for i64`
- `impl One for f32`
- `impl One for f64`
- `impl<T: One> One for Wrapping<T> where
  Wrapping<T>: Mul<Output = Wrapping<T>>,`

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