code: func Verify16(a, b *[16]byte) bool {
  	if a == nil || b == nil {
  		panic("nacl: nil input")
  	}
  	return subtle.ConstantTimeCompare(a[:], b[:]) == 1
  }
docs: // Verify16 returns true if and only if a and b have equal contents, without
  // leaking timing information.