Re: yacc parse tree

> [Seems to me you're just building your own stack parallel to the one
> that yacc already keeps for you. I don't see the advantage of storing
> the tree pointer in a global, other than the final top-level tree since
> yacc doesn't let you return it from yyparse(). -John]


no, it wasn't what I meant. it's like this :


top level


tnode* last;


yyparse() {
..
yyreduce:
{
last = a new node where children are
yyvsp[-1..-yylen[yyn]]
}
..
}


I mean, I don't keep a stack, I keep the root of the tree built so far.
when yyparse() returns, we have the root at the pointer "last". the stack
which yyparse() keeps reduces to size 0 when $accept reduces.
( there's a line yyvsp -= yym after yyreduce: )


****************************************************************************
Sukru Cinar scinar@ug.bcc.bilkent.edu.tr
YetNotGraduate Computer Science Student in Bilkent/Turkey
[I suppose that if for some reason you hate saying $2 you could do that.
But the only place you need to assign to last is in the start rule. -John]

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