Re: Help about file lalr

[Akim Demaille]

>>>>> "Carlos" == Carlos Javier Borges Villalba <address@hidden> writes:

Carlos> I would like to know what bison does in file lalr.c. What does
Carlos> bison intend to do in lalr.c?

You probably know that an LALR(1) automaton as the same layout as the
LR(0) one.  So, once it has built the LR(0) automaton, in lalr.c it
uses smart algorithms that adds lookaheads to the LR(0) automaton.
This algo uses back propagation.  Look on the web, I know you can find
this info somewhere, I don't recall where.

Carlos> What does digraph and build_relations do? Where can I find
Carlos> theory about that?

You already asked this, we already said we don't know.


Carlos> As some people know i am analyzing Bison's source in order to
Carlos> implement another method (dr)

Just as Hans, I fail to see the point.  You certainly don't care about
LALR(1).

Carlos> About that implementation we have a beta version.  In the
Carlos> implementation we have for sure to add a "special" rule in
Carlos> order the method works.

Carlos> That rule is the start_symbol_prima ---> _ _ start_symbol
Carlos> $. (add a double start of file and end of file mark) We use
Carlos> Bison in its normal way until the function
Carlos> generate_states. Then we change the rest even the bison.simple
Carlos> file.  But we have to debug the method and clean and optimize
Carlos> code.  If somebody wants further information just ask me ;)

As I said, IMHO, you made a mistake working on Bison without
collaborating with us.  Bison has changed a lot, and the merge will
drive you crazy.