def OverflowingSub.value

bend-collections-laws-math@1.0.0.0 · spec/math/fixed.bend:152

import Base
import bend-collections-laws-math@1.0.0.0/spec/lib/common.bend as C
import bend-collections-laws-math@1.0.0.0/src/math/fixed.bend as F

152def OverflowingSub.value(~T: Data, ~val: T -> Nat, ~f: @+x: T -> @+y: T -> F.Over<T>, +w: Nat, +a: T, +b: T) -> Type:
153  {Nat.add(ov_val(~T, ~val, f(a, b)), val(b)) == Nat.add(val(a), C.shift(w, bn(Nat.is_lt(val(a), val(b))))) : Nat}