%{
use 5.0010;
use feature 'state';
my $is_enum = 0;

sub rangeORenum {
  my $self = shift; 

  require Range;
  state $rp = Range->new( yyerror => sub {});

  my $pos = pos(${$self->input});
  $rp->input($self->input);
  my $t = $rp->Run;
  print "After nested parsing\n";
  $is_enum = $rp->YYNberr;
  pos(${$self->input}) = $pos;
}

%}

%conflict rangeORenum {
  if ($is_enum) { $self->YYSetReduce([',', ')'], 'ID:ENUM' ); }
  else { $self->YYSetReduce([',', ')'], 'ID:RANGE' ); }
} 

%token ID  = /([A-Za-z]\w*)/
%token NUM = /(\d+)/

%left   ','
%left   '-' '+'
%left   '*' '/'

%expect-rr 2

%%

type_decl : 'type' ID '=' type ';'
;

type : 
      %name ENUM
      PRErangeORenum '(' id_list ')'
    | %name RANGE
      PRErangeORenum expr '..' expr
;

PRErangeORenum:
   /* empty */  
     {
       goto &rangeORenum;
     }
;

id_list : 
      %name ID:ENUM
      ID                      %PREC rangeORenum
    | id_list ',' ID
;

expr : '(' expr ')'   { $_[2] } /* bypass */
    | %name PLUS     expr '+' expr
    | %name MINUS    expr '-' expr
    | %name TIMES    expr '*' expr
    | %name DIV      expr '/' expr
    | %name COMMA    expr ',' expr
    | %name ID:RANGE
      ID                     %PREC rangeORenum
    | %name NUM      NUM
;

%%

=head1 SYNOPSIS

See 

=over 2

=item * File C<userange.pl>.

=item * File C<Range.eyp>.

=item * File pascalenumeratedvsrange.eyp in examples/debuggintut/

=item * The Bison manual L<http://www.gnu.org/software/bison/manual/html_mono/bison.html>

=back

Compile it with:

      eyapp Range.eyp
      eyapp -TC pascalnestedeyapp.eyp

Run it with this options:

    $ ./pascalnestedeyapp.pm -t -i -m 1 -c 'type e = (x, y, z);'
    $ perl5.10.0 ./pascalnestedeyapp.pm -t -i -m 1 -c 'type e = (x, @, z);'

Try also these inputs:

                type e = (x) .. (y);
                type r = (x) ..  y ;
                type r = (x+2)*3 ..  y/2 ;
                type e = (x, y, z);
                type e = (x);
                type e = (x, y, z) .. (u+v);


=cut