/// <summary>
/// 获取语法树堆栈的顶级记号
/// </summary>
/// <param name="SyntaxTreeStack">语法树堆栈</param>
/// <returns>顶级记号Hash</returns>
/// <remarks>Author:Alex Leo</remarks>
private static TokenRecord.TokenRecord SyntaxTreeStackGetTopToken(Stack <TokenRecord.TokenRecord> SyntaxTreeStack)
{
TokenRecord.TokenRecord TempToken = null;
if (SyntaxTreeStack.Count > 0)
{
TempToken = SyntaxTreeStack.Pop();
while (SyntaxTreeStack.Count > 0)
{
SyntaxTreeStack.Peek().ChildList.Add(TempToken);
TempToken = SyntaxTreeStack.Pop();
}
}
return(TempToken);
}
/// <summary>
/// 语法树堆栈分析，基于记号的优先级
/// </summary>
/// <param name="SyntaxTreeStack">语法树堆栈</param>
/// <param name="NewToken">新记号</param>
/// <remarks>Author:Alex Leo</remarks>
private static void SyntaxTreeStackAnalyse(Stack <TokenRecord.TokenRecord> SyntaxTreeStack, TokenRecord.TokenRecord NewToken)
{
if (SyntaxTreeStack.Count == 0) //如果语法树堆栈中不存在记号，则直接压栈
{
SyntaxTreeStack.Push(NewToken);
}
else //否则，比较优先级进行栈操作
{
//比较优先级，如果新Token优先级高，则压栈；
//如果新Token优先级低，则弹栈，把弹出的Token设置为新Token的下级，并把新Token压栈；
//相同优先级也弹栈，并将新Token压栈
//if (this.m_DicTokenTypePriority[SyntaxTreeStack.Peek().TokenType] < this.m_DicTokenTypePriority[NewToken.TokenType])//低进
if (SyntaxTreeStack.Peek().Priority < NewToken.Priority) //低进
{
SyntaxTreeStack.Push(NewToken); //低进
}
else
{
TokenRecord.TokenRecord TempToken = null;
//如果堆栈中有记号，并且栈顶的记号优先级大于等于新记号的优先级，则继续弹栈
while (SyntaxTreeStack.Count > 0 && (SyntaxTreeStack.Peek().Priority >= NewToken.Priority))
{
TempToken = SyntaxTreeStack.Pop();
if (SyntaxTreeStack.Count > 0) //检测栈顶是否可能为空，如果为空则退出
{
if (SyntaxTreeStack.Peek().Priority >= NewToken.Priority)
{
SyntaxTreeStack.Peek().ChildList.Add(TempToken);
}
else
{
NewToken.ChildList.Add(TempToken);
}
}
else
{
NewToken.ChildList.Add(TempToken);
}
}
SyntaxTreeStack.Push(NewToken); //压栈
}
}
}