%{
=head1 SYNOPSIS

This example illustrates a way to set a naming scheme for
the grammar productions using C<give_token_name>.
give_token_name: The name of the production is the Left Hand Side
of the Production Rule followed by the word _is_ followed by the
concatenation of the names of the tokens in the right hand side
(separated by underscores).

Compile it with:

                $ eyapp -C give_names_to_tokens.eyp 

and run it:
                  $ ./give_names_to_tokens.pm -t -i -c '*a = b'

It will produce an output like:

    s_is_ASSIGN(l_is_STAR(r_is_l(l_is_VAR(TERMINAL[a]))),r_is_l(l_is_VAR(TERMINAL[b])))

The main difference between this file and C<give_token_names.eyp>
is that here  C<'='> and C<'*'> are used and therefore we must associate
with them identifiers via the method C<tokennames>.

=cut
%}

%token VAR = /([A-Za-z][A-Za-z0-9_]*)/

%namingscheme { 
  #Receives a Parse::Eyapp object describing the grammar
  my $self = shift;

  $self->tokennames(
    '=' => 'ASSIGN',
    '*' => 'STAR',
  );

  # returns the handler that will give names 
  # to the right hand sides
  \&give_token_name; 
}

%tree

%%
s:
    l '=' r
  | r
;

l:
    '*' r
  | VAR
;

r:
    l
;

%%