Trait snarkvm_circuit::Sub

1.0.0 · source · 
pub trait Sub<Rhs = Self> {
    type Output;

    fn sub(self, rhs: Rhs) -> Self::Output;
}
Expand description

The subtraction operator -.

Note that Rhs is Self by default, but this is not mandatory. For example, std::time::SystemTime implements Sub<Duration>, which permits operations of the form SystemTime = SystemTime - Duration.

Examples

Subtractable points

use std::ops::Sub;

#[derive(Debug, Copy, Clone, PartialEq)]
struct Point {
    x: i32,
    y: i32,
}

impl Sub for Point {
    type Output = Self;

    fn sub(self, other: Self) -> Self::Output {
        Self {
            x: self.x - other.x,
            y: self.y - other.y,
        }
    }
}

assert_eq!(Point { x: 3, y: 3 } - Point { x: 2, y: 3 },
           Point { x: 1, y: 0 });

Implementing Sub with generics

Here is an example of the same Point struct implementing the Sub trait using generics.

use std::ops::Sub;

#[derive(Debug, PartialEq)]
struct Point<T> {
    x: T,
    y: T,
}

// Notice that the implementation uses the associated type `Output`.
impl<T: Sub<Output = T>> Sub for Point<T> {
    type Output = Self;

    fn sub(self, other: Self) -> Self::Output {
        Point {
            x: self.x - other.x,
            y: self.y - other.y,
        }
    }
}

assert_eq!(Point { x: 2, y: 3 } - Point { x: 1, y: 0 },
           Point { x: 1, y: 3 });

Required Associated Types

The resulting type after applying the - operator.

Required Methods

Performs the - operation.

Example
assert_eq!(12 - 1, 11);

Trait Implementations

Returns the number of constants, public inputs, private inputs, and constraints.
Returns the number of constants, public inputs, private inputs, and constraints.
Returns the number of constants, public inputs, private inputs, and constraints.
Returns the mode of the output.
Returns the mode of the output.
Returns the mode of the output.

Implementors

UTerm - B0 = Term

UInt<UTerm, B1> - B1 = UTerm

Z0 - Z0 = Z0

UTerm - UTerm = UTerm

UInt<U, B0> - B1 = UInt<U - B1, B1>

Z0 - N = P

Z0 - P = N

NInt - Z0 = NInt

PInt - Z0 = PInt

UInt - B0 = UInt

UInt<U, B1> - B1 = UInt<U, B0>

Subtracting unsigned integers. We just do our PrivateSub and then Trim the output.

N(Ul) - N(Ur): We resolve this with our PrivateAdd

P(Ul) - N(Ur) = P(Ul + Ur)

N(Ul) - P(Ur) = N(Ul + Ur)

P(Ul) - P(Ur): We resolve this with our PrivateAdd