//执行函数校验
private ExpressionToken VerifyFunction(ExpressionToken funtionToken, Stack <ExpressionToken> verifyStack)
{
if (!(verifyStack.Count == 0))
{
bool doPop = true;
var args = new List <BaseMetadata>();
ExpressionToken parameter = null;
//弹出函数的参数，直到遇到"("时终止
while (doPop && !(verifyStack.Count == 0))
{
parameter = verifyStack.Pop();
if (ExpressionToken.ETokenType.ETOKEN_TYPE_CONSTANT == parameter.TokenType)
{
//常量
args.Add(parameter.Constant);
}
else if (ExpressionToken.ETokenType.ETOKEN_TYPE_VARIABLE == parameter.TokenType)
{
args.Add(parameter.Variable);
}
else if ("(".Equals(parameter.GetSplitor()))
{
doPop = false;
}
else
{
//没有找到应该存在的右括号
throw new IllegalExpressionException("表达式不合法，函数\"" + funtionToken.TokenText + "\"遇到非法参数" + parameter.ToString() + ";位置:" + parameter.StartPosition
, funtionToken.ToString()
, funtionToken.StartPosition);
}
}
if (doPop && (verifyStack.Count == 0))
{
//操作栈以空，没有找到函数的左括号（
throw new IllegalExpressionException("表达式不合法，函数\"" + funtionToken.TokenText + "\"缺少\"(\"；位置:" + (funtionToken.StartPosition + funtionToken.ToString().Length)
, funtionToken.ToString()
, funtionToken.StartPosition);
}
//校验函数
var arguments = new BaseMetadata[args.Count];
arguments = args.ToArray();
Constant result = FunctionExecution.Verify(funtionToken.TokenText, funtionToken.StartPosition, arguments);
return(ExpressionToken.CreateConstantToken(result));
}
else
{
//没有找到应该存在的右括号
throw new IllegalExpressionException("表达式不合法，函数\"" + funtionToken.TokenText + "\"不完整"
, funtionToken.ToString()
, funtionToken.StartPosition);
}
}
public Reference(ExpressionToken token, Constant[] args)
{
this.Token = token;
this.Arguments = args;
//记录Reference实际的数据类型
if (ExpressionToken.ETokenType.ETOKEN_TYPE_FUNCTION == token.TokenType)
{
Constant result = FunctionExecution.Verify(token.TokenText, token.StartPosition, args);
dataType = result.GetDataType();
}
else if (ExpressionToken.ETokenType.ETOKEN_TYPE_OPERATOR == token.TokenType)
{
Operator op = token.Op;
Constant result = op.Verify(token.StartPosition, args);
dataType = result.GetDataType();
}
}