%{
=head1 SYNOPSIS

compile it with 

  eyapp -b '/usr/bin/perl -I ../Calculator/lib' Precedencia.eyp

execute the generated modulino with:

      ./Precedencia.pm -nos -c '2@3@4' -info 

Try also with inputs:
   
    4@3@5
    4@3&5
    4&3@5
    4&3&5

The result will be the term describing the generated
Abstract Syntax Tree 

=head1 See also

    http://search.cpan.org/perldoc?Parse::Eyapp::debuggingtut

=cut

%}

%token NUM=/(\d+)/
%left '@'
%right '&'  dummy

%tree bypass
%%
list
    : /* empty */
    | list '\n' {}
    | $list $e { print $e->str."\n"; 
                 $e->png('tree'); 
                 $e; 
               }
    ;

e : %name NUM
      NUM
  | %name AMPERSAND
      e '&' e
  | %name AT
      e '@' e %prec dummy
  ;

%%