sub

Subtracts two field elements (mod m).

Function parameters

Parameters

self:Self
x:Fe
y:Fe

An unsigned big integer with a fixed maximum size (`max_bits`), suitable for cryptographic operations.

Functions

Uint: An unsigned big integer with a fixed maximum size (`max_bits`), suitable for cryptographic operations.
Modulus: A modulus, defining a finite field.

Error sets in this namespace

Error Sets

OverflowError: Value is too large for the destination.
InvalidModulusError: Invalid modulus.
NullExponentError: Exponentiation with a null exponent.
FieldElementError: Invalid field element for the given modulus.
RepresentationError: Invalid representation (Montgomery vs non-Montgomery domain.)
Error: The set of all possible errors `std.crypto.ff` functions can return.

Source

Implementation

pub fn sub(self: Self, x: Fe, y: Fe) Fe {
    var out = x;
    const underflow: bool = @bitCast(out.v.subWithOverflow(y.v));
    _ = out.v.conditionalAddWithOverflow(underflow, self.v);
    return out;
}