$^W=0;

use Parse::Yapp;

my($parser,$grammar);
my($yapptxt);

$grammar=join('',<DATA>);
$parser=new Parse::Yapp(input => $grammar);
$yapptxt=$parser->Output(classname => 'MyParser');
eval $yapptxt;

my($parser);
  $parser=new MyParser();
  $parser->YYData->{DATA}= [ "a and B\n" ];
  $data=$parser->YYData->{DATA}[0];
print "data=[$data]\n";

exit;

__DATA__

%%

CCLFind:    CCLFind Op Elements
             | Elements
;

Op:    'and' | 'or' | 'not'
;
#  -- The above means that Elements are separated by boolean operators
+.

  Elements:    '(' CCLFind ')'
#!             | Set
             | Terms
             | Qualifiers Relation Terms
             | Qualifiers Relation '(' CCLFind ')'
             | Qualifiers '=' string '-' string
;
#  -- Elements is either a recursive definition, a result set referenc
+e, a
#  -- list of terms, qualifiers followed by terms, qualifiers followed
#  -- by a recursive definition or qualifiers in a range (lower - uppe
+r).

#!Set:    'set' = string
#!;
#  -- Reference to a result set

  Terms:    Terms Prox Term
          | Term
;
#  -- Proximity of terms.

  Term:    Term string
         | string
;
#  -- This basically means that a term may include a blank

  Qualifiers:    Qualifiers ',' string
               | string
;
#  -- Qualifiers is a list of strings separated by comma

  Relation:    '=' | '>=' | '<=' | '<>' | '>' | '<'
;
#  -- Relational operators. This really doesn't follow the ISO8777
#  -- standard.

  Prox:    '%' | '!'
;
#  -- Proximity operator


%%

sub _Error {
        exists $_[0]->YYData->{ERRMSG}
    and do {
        print $_[0]->YYData->{ERRMSG};
        delete $_[0]->YYData->{ERRMSG};
        return;
    };
    print "Syntax error.\n";
}

sub _Lexer {
    my($parser)=shift;

        $parser->YYData->{INPUT}
    or  $parser->YYData->{INPUT} = <STDIN>
    or  return('',undef);

    $parser->YYData->{INPUT}=~s/^[ \t]//;

    for ($parser->YYData->{INPUT}) {
        s/^([0-9]+(?:\.[0-9]+)?)//
                and return('NUM',$1);
        s/^([A-Za-z][A-Za-z0-9_]*)//
                and return('VAR',$1);
        s/^(.)//s
                and return($1,$1);
    }
}

sub Run {
    my($self)=shift;
    $self->YYParse( yylex => \&_Lexer, yyerror => \&_Error );
}
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• How do I add my functions to process the searching?

Edited: ~Mon Oct 21 19:36:02 2002 (GMT) by footpad: Added <readmore> tag, per Consideration