# Trait ethcore_util::standard::ops::Div 1.0.0 [−] [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));
    }

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]});

## 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<U512> for U512`
- `impl Div<U256> for U256`
- `impl Div<U128> for U128`
- `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<i32> for Duration`
- `impl Div<u32> for Duration`

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