def zs
bend-collections-laws-math@1.0.0.0 · proofs/math/typed/f64modf.bend:67
import bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64modf.bend as F64modf
import Base
import bend-collections-laws-math@1.0.0.0/spec/math/f64.bend as SF
import bend-collections-laws-math@1.0.0.0/src/math/f64.bend as F
import bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64bits.bend as FB
import bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64tools.bend as T
67def zs(+x: F.F64) -> {F.zero(F.signbit(x)) == SF.zero(SF.sign(x)) : F.F64}:
68 Equal.trans(F.F64, F.zero(F.signbit(x)), SF.zero(F.signbit(x)), SF.zero(SF.sign(x)), T.zero_v(F.signbit(x)), Equal.cong(Bool, F.F64, t => SF.zero(t), F.signbit(x), SF.sign(x), FB.signbit_value(x)))