Re: Shift reduce errors due to embedded actions

[Axel Kittenberger]

> i have developed a parser for a language similar to c to generate the cross
> reference information of variables and function names used in the source
> code.
 
> from the embedded actions in the rules section of bison, i invoke a
> function to generate cross reference information about the variables in the
> program, which leads to shift reduce errors.
 
> how can i avoid getting the shift reduce errors due to embedded actions in
> the rules section of bison?
 
> is there any way where i can do away with embedded actions while achieving
> the purpose of generating the cross reference information?
 

Well the answer is simply, but the actions at the end....

I the parser has something like
A B C {action1}
A B D {action2}

there is no problem...
but if it has
A {action1} B C 
A {action2} B D 

The parser cannot decide when it looked at A (and looked forward to B) if it 
shall execute action1 or action2, 

as far I understood parser stuff, this is a limition of bisons LALR 
algorithm, which is LR(1). (1 look ahead), LR(n) is theoretically possibly, 
but I don't know of a open implementation of it. Altough I don't know too 
much about this parser theory stuff, so please correct :o)

- Axel

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