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=head1 SYNOPSIS

A deliberately confusing example

For this grammar, an example input that starts C<x y c> is enough to confuse an
LR(1) parser, as it has to decide whether C<x y> matches B or E after only seeing
1 symbol further (i.e. c).

An LL(1) parser would also be confused, but at the C<x> - should it expand C<A> to
C<B c d> or to C<E c f>, as both can start with C<x>. An LL(2) or LL(3) parser
would have similar problems at the y or c respectively.

An LR(2) parser would be able to also see the d or f that followed the c and so
make the correct choice between B and E.

An LL(4) parser would also be able to look far enough ahead to see the d or f
that followed the c and so make the correct choice between expanding A to B c d
or to E c f. 


=head1 SEE ALSO

I have seen this example at Jinks page:
L<http://www.cs.man.ac.uk/~pjj>

Different solutions can be found in files:

   confusingsolvedstatic.eyp 
   confusingsolvedstatic2.eyp 
   confusingsolveddynamic.eyp

See 

   http://www.cs.man.ac.uk/~pjj/cs2121/ho/node19.html

=cut

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%%
A: 
    B 'c' 'd' 
  | E 'c' 'f' 
;
B: 
    'x' 'y' 
;
E: 
    'x' 'y' 
;
%%