%{

=head1 SYNOPSIS 

This example illustrates how to solve the conflict in
C<nolr_k_grammar.eyp> using 
the postponed conflict resolution technique.

Compile the grammar with:

                 eyapp -b '' nolr_k_grammarsolveddynamic.eyp

and execute it with:

                ./nolr_k_grammarsolveddynamic.pm -t


=head1 SEE ALSO

=over 2

=item * See file C<nolr_k_grammar.eyp>

=item * This is inspired in an example I have seen this example 
at Pete Jinks page: L<http://www.cs.man.ac.uk/~pjj>

=item * See another solution in file: C<lr_1_grammar.eyp>

=back

=cut 

use base q{DebugTail}; 

%}

%expect 0 1

%semantic token 'c' 'd' 'f' 'x' 'y'
%tree 

%%
A: 
    %name BCd
    B C 'd' 
  | %name ECf
    E C 'f' 
;
B:  %name B
    'x' 'y' dORfconflict
;
E:  %name E
    'x' 'y' dORfconflict
;
C: 
    %name C
    /* empty */
  | %name Cs
    C 'c' 
;

dORfconflict:
      /* empty. Just to solve the reduce-reduce conflict */
      {
        my $self = shift;

        if (${$self->input()} =~ m{^.*?d}) {
          $self->YYSetReduce(['c', 'd'], 'B' );
        }
        else {
          $self->YYSetReduce(['c', 'f'], 'E' ); 
        }
        undef;
      }
;

%%

unless (caller) {
  my $prompt = 'Try "x y c c c f" and "x y f". Press <CR><CTRL-D> to finish: ';
  __PACKAGE__->main($prompt)
}