internal ConstantListItem(Object term, ConstantListItem prev){
this.prev = prev;
this.term = term;
}
private object PPScanExpr()
{
object obj2;
OpListItem prev = new OpListItem(JSToken.None, OpPrec.precNone, null);
ConstantListItem item2 = new ConstantListItem(this.PPScanConstant(), null);
while (true)
{
this.GetNextToken();
if (!IsPPOperator(this.currentToken.token))
{
goto Label_00E4;
}
OpPrec pPOperatorPrecedence = GetPPOperatorPrecedence(this.currentToken.token);
while (pPOperatorPrecedence < prev._prec)
{
obj2 = this.PPGetValue(prev._operator, item2.prev.term, item2.term);
prev = prev._prev;
item2 = item2.prev.prev;
item2 = new ConstantListItem(obj2, item2);
}
prev = new OpListItem(this.currentToken.token, pPOperatorPrecedence, prev);
item2 = new ConstantListItem(this.PPScanConstant(), item2);
}
Label_00AB:
obj2 = this.PPGetValue(prev._operator, item2.prev.term, item2.term);
prev = prev._prev;
item2 = item2.prev.prev;
item2 = new ConstantListItem(obj2, item2);
Label_00E4:
if (prev._operator != JSToken.None)
{
goto Label_00AB;
}
this.currentPos = this.currentToken.startPos;
return item2.term;
}
private Object PPScanExpr(){
OpListItem opsStack = new OpListItem(JSToken.None, OpPrec.precNone, null); // dummy element
ConstantListItem termStack = new ConstantListItem(PPScanConstant(), null);
Object value;
for (;;){
GetNextToken();
if (JSScanner.IsPPOperator(this.currentToken.token)){
OpPrec prec = JSScanner.GetPPOperatorPrecedence(this.currentToken.token);
while (prec < opsStack._prec){
//Console.Out.WriteLine("lower prec or same and left assoc");
value = PPGetValue(opsStack._operator, termStack.prev.term, termStack.term);
// pop the operator stack
opsStack = opsStack._prev;
// pop the term stack twice
termStack = termStack.prev.prev;
// push node onto the stack
termStack = new ConstantListItem(value, termStack);
}
// the current operator has higher precedence that every scanned operators on the stack, or
// it has the same precedence as the one at the top of the stack and it is right associative
// push the operator onto the operators stack
opsStack = new OpListItem(this.currentToken.token, prec, opsStack);
// push new term
termStack = new ConstantListItem(PPScanConstant(), termStack);
}else{
//Console.Out.WriteLine("unwinding stack");
// there are still operators to be processed
while (opsStack._operator != JSToken.None){
// make the ast operator node
value = PPGetValue(opsStack._operator, termStack.prev.term, termStack.term);
// pop the operator stack
opsStack = opsStack._prev;
// pop the term stack twice
termStack = termStack.prev.prev;
// push node onto the stack
termStack = new ConstantListItem(value, termStack);
}
// reset position into stream
this.currentPos = this.currentToken.startPos;
break; // done
}
}
Debug.Assert(termStack.prev == null);
return termStack.term;
}
internal ConstantListItem(object term, ConstantListItem prev)
{
this.prev = prev;
this.term = term;
}