fn sub(r: *Mutable, a: Const, b: Const) void

r = a - b

r, a and b may be aliases.

Asserts the result fits in r. An upper bound on the number of limbs needed by r is @max(a.limbs.len, b.limbs.len) + 1. The +1 is not needed if both operands are positive.

Parameters

r: *Mutable,
a: Const,
b: Const,