LR(1) Confusion...

Hi All,


I'm working on an LR(1) parser generator and I have several questions.


1. Do you know of any good C/C++ LR(1) parser generator out there?
I've scanned the net but couldn't find any. Also, a simple LR(1)
binary would also be good for testing my own source.


2. I have an example which seems very odd; The book does have several
mistakes so I presume that this is yet another one, but since I don't
have too MANY examples, I can't really be sure that my implementation
is correct. The example goes like that -


S->E$
E->T+E
E->T
E->x
T->x
------------
Closure(I0) comes out (in the example) like that:
S->.E$ ?
E->.T+E $
E->.T $
E->.x +
E->.x $


And in my application it comes out like that:
S->.E$ $
E->.T+E $
E->.T $
E->.x $
T->.x +
T->.x $


Now, I passed on the algorithm and I don't understand how can it be
that the example doesn't contain, for example {T->.x,+}. As I
understood it, the algorithm carries on with its search until no more
changes occur - and if you take E->.T+E and test it, you get Beta as
"+", of which First("+")="+" since it's terminal, and there you have
the (T->.x,+).


Can someone please explain?


Thanks a lot!

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