# Trait std::ops::Div1.0.0 [−] [src]

```pub trait Div<RHS = Self> {
type Output;
fn div(self, rhs: RHS) -> Self::Output;
}```

The `Div` trait is used to specify the functionality of `/`.

# Examples

Implementing a `Div`idable rational number struct:

```use std::ops::Div;

// The uniqueness of rational numbers in lowest terms is a consequence of
// the fundamental theorem of arithmetic.
#[derive(Eq)]
#[derive(PartialEq, Debug)]
struct Rational {
nominator: usize,
denominator: usize,
}

impl Rational {
fn new(nominator: usize, denominator: usize) -> Self {
if denominator == 0 {
panic!("Zero is an invalid denominator!");
}

// Reduce to lowest terms by dividing by the greatest common
// divisor.
let gcd = gcd(nominator, denominator);
Rational {
nominator: nominator / gcd,
denominator: denominator / gcd,
}
}
}

impl Div for Rational {
// The division of rational numbers is a closed operation.
type Output = Self;

fn div(self, rhs: Self) -> Self {
if rhs.nominator == 0 {
panic!("Cannot divide by zero-valued `Rational`!");
}

let nominator = self.nominator * rhs.denominator;
let denominator = self.denominator * rhs.nominator;
Rational::new(nominator, denominator)
}
}

// Euclid's two-thousand-year-old algorithm for finding the greatest common
// divisor.
fn gcd(x: usize, y: usize) -> usize {
let mut x = x;
let mut y = y;
while y != 0 {
let t = y;
y = x % y;
x = t;
}
x
}

fn main() {
assert_eq!(Rational::new(1, 2), Rational::new(2, 4));
assert_eq!(Rational::new(1, 2) / Rational::new(3, 4),
Rational::new(2, 3));
}Run```

Note that `RHS = Self` by default, but this is not mandatory. Here is an implementation which enables division of vectors by scalars, as is done in linear algebra.

```use std::ops::Div;

struct Scalar {value: f32};

#[derive(Debug)]
struct Vector {value: Vec<f32>};

impl Div<Scalar> for Vector {
type Output = Vector;

fn div(self, rhs: Scalar) -> Vector {
Vector {value: self.value.iter().map(|v| v / rhs.value).collect()}
}
}

impl PartialEq<Vector> for Vector {
fn eq(&self, other: &Self) -> bool {
self.value == other.value
}
}

let scalar = Scalar{value: 2f32};
let vector = Vector{value: vec![2f32, 4f32, 6f32]};
assert_eq!(vector / scalar, Vector{value: vec![1f32, 2f32, 3f32]});Run```

## Associated Types

### `type Output`

The resulting type after applying the `/` operator

## Required Methods

### `fn div(self, rhs: RHS) -> Self::Output`

The method for the `/` operator

## Implementors

• `impl Div<Wrapping<usize>> for Wrapping<usize>`
• `impl Div<Wrapping<u8>> for Wrapping<u8>`
• `impl Div<Wrapping<u16>> for Wrapping<u16>`
• `impl Div<Wrapping<u32>> for Wrapping<u32>`
• `impl Div<Wrapping<u64>> for Wrapping<u64>`
• `impl Div<Wrapping<isize>> for Wrapping<isize>`
• `impl Div<Wrapping<i8>> for Wrapping<i8>`
• `impl Div<Wrapping<i16>> for Wrapping<i16>`
• `impl Div<Wrapping<i32>> for Wrapping<i32>`
• `impl Div<Wrapping<i64>> for Wrapping<i64>`
• `impl<'a> Div<Wrapping<usize>> for &'a Wrapping<usize>`
• `impl<'a> Div<&'a Wrapping<usize>> for Wrapping<usize>`
• `impl<'a, 'b> Div<&'a Wrapping<usize>> for &'b Wrapping<usize>`
• `impl<'a> Div<Wrapping<u8>> for &'a Wrapping<u8>`
• `impl<'a> Div<&'a Wrapping<u8>> for Wrapping<u8>`
• `impl<'a, 'b> Div<&'a Wrapping<u8>> for &'b Wrapping<u8>`
• `impl<'a> Div<Wrapping<u16>> for &'a Wrapping<u16>`
• `impl<'a> Div<&'a Wrapping<u16>> for Wrapping<u16>`
• `impl<'a, 'b> Div<&'a Wrapping<u16>> for &'b Wrapping<u16>`
• `impl<'a> Div<Wrapping<u32>> for &'a Wrapping<u32>`
• `impl<'a> Div<&'a Wrapping<u32>> for Wrapping<u32>`
• `impl<'a, 'b> Div<&'a Wrapping<u32>> for &'b Wrapping<u32>`
• `impl<'a> Div<Wrapping<u64>> for &'a Wrapping<u64>`
• `impl<'a> Div<&'a Wrapping<u64>> for Wrapping<u64>`
• `impl<'a, 'b> Div<&'a Wrapping<u64>> for &'b Wrapping<u64>`
• `impl<'a> Div<Wrapping<isize>> for &'a Wrapping<isize>`
• `impl<'a> Div<&'a Wrapping<isize>> for Wrapping<isize>`
• `impl<'a, 'b> Div<&'a Wrapping<isize>> for &'b Wrapping<isize>`
• `impl<'a> Div<Wrapping<i8>> for &'a Wrapping<i8>`
• `impl<'a> Div<&'a Wrapping<i8>> for Wrapping<i8>`
• `impl<'a, 'b> Div<&'a Wrapping<i8>> for &'b Wrapping<i8>`
• `impl<'a> Div<Wrapping<i16>> for &'a Wrapping<i16>`
• `impl<'a> Div<&'a Wrapping<i16>> for Wrapping<i16>`
• `impl<'a, 'b> Div<&'a Wrapping<i16>> for &'b Wrapping<i16>`
• `impl<'a> Div<Wrapping<i32>> for &'a Wrapping<i32>`
• `impl<'a> Div<&'a Wrapping<i32>> for Wrapping<i32>`
• `impl<'a, 'b> Div<&'a Wrapping<i32>> for &'b Wrapping<i32>`
• `impl<'a> Div<Wrapping<i64>> for &'a Wrapping<i64>`
• `impl<'a> Div<&'a Wrapping<i64>> for Wrapping<i64>`
• `impl<'a, 'b> Div<&'a Wrapping<i64>> for &'b Wrapping<i64>`
• `impl Div<usize> for usize`
• `impl Div<u8> for u8`
• `impl Div<u16> for u16`
• `impl Div<u32> for u32`
• `impl Div<u64> for u64`
• `impl Div<isize> for isize`
• `impl Div<i8> for i8`
• `impl Div<i16> for i16`
• `impl Div<i32> for i32`
• `impl Div<i64> for i64`
• `impl<'a> Div<usize> for &'a usize`
• `impl<'a> Div<&'a usize> for usize`
• `impl<'a, 'b> Div<&'a usize> for &'b usize`
• `impl<'a> Div<u8> for &'a u8`
• `impl<'a> Div<&'a u8> for u8`
• `impl<'a, 'b> Div<&'a u8> for &'b u8`
• `impl<'a> Div<u16> for &'a u16`
• `impl<'a> Div<&'a u16> for u16`
• `impl<'a, 'b> Div<&'a u16> for &'b u16`
• `impl<'a> Div<u32> for &'a u32`
• `impl<'a> Div<&'a u32> for u32`
• `impl<'a, 'b> Div<&'a u32> for &'b u32`
• `impl<'a> Div<u64> for &'a u64`
• `impl<'a> Div<&'a u64> for u64`
• `impl<'a, 'b> Div<&'a u64> for &'b u64`
• `impl<'a> Div<isize> for &'a isize`
• `impl<'a> Div<&'a isize> for isize`
• `impl<'a, 'b> Div<&'a isize> for &'b isize`
• `impl<'a> Div<i8> for &'a i8`
• `impl<'a> Div<&'a i8> for i8`
• `impl<'a, 'b> Div<&'a i8> for &'b i8`
• `impl<'a> Div<i16> for &'a i16`
• `impl<'a> Div<&'a i16> for i16`
• `impl<'a, 'b> Div<&'a i16> for &'b i16`
• `impl<'a> Div<i32> for &'a i32`
• `impl<'a> Div<&'a i32> for i32`
• `impl<'a, 'b> Div<&'a i32> for &'b i32`
• `impl<'a> Div<i64> for &'a i64`
• `impl<'a> Div<&'a i64> for i64`
• `impl<'a, 'b> Div<&'a i64> for &'b i64`
• `impl Div<f32> for f32`
• `impl Div<f64> for f64`
• `impl<'a> Div<f32> for &'a f32`
• `impl<'a> Div<&'a f32> for f32`
• `impl<'a, 'b> Div<&'a f32> for &'b f32`
• `impl<'a> Div<f64> for &'a f64`
• `impl<'a> Div<&'a f64> for f64`
• `impl<'a, 'b> Div<&'a f64> for &'b f64`
• `impl Div<u32> for Duration`