docs: private static Type getTypeOfSubtract(BinaryTree expression, VisitorState state) {
      Type expressionType = ASTHelpers.getType(expression.getLeftOperand());
      if (!ASTHelpers.isSameType(
          expressionType, ASTHelpers.getType(expression.getRightOperand()), state)) {
        return ASTHelpers.getType(expression);
      }
      return expressionType;
    }