code: func opcodeNumEqualVerify(op *parsedOpcode, vm *Engine) error {
  	err := opcodeNumEqual(op, vm)
  	if err == nil {
  		err = abstractVerify(op, vm, ErrNumEqualVerify)
  	}
  	return err
  }
docs: // opcodeNumEqualVerify is a combination of opcodeNumEqual and opcodeVerify.
  //
  // Specifically, treats the top two items on the data stack as integers.  When
  // they are equal, they are replaced with a 1, otherwise a 0.  Then, it examines
  // the top item on the data stack as a boolean value and verifies it evaluates
  // to true.  An error is returned if it does not.
  //
  // Stack transformation: [... x1 x2] -> [... bool] -> [...]