There are two problems here. First, your grammar is not quite right. And secondly, you aren't setting the return in your starting rule.

I'm not an expert with Parse::RecDescent, or with constructing grammars for YACC, Bison, etc.(far from it, actually); but IMHO, you probably don't want the { $return = $item[1] } on the 'var_name:' rule.

Instead, I think you want it on the 'statement:' AND 'varStatement:' rules (see below). Also, removing the 'comma:' rule and replacing its use with literal commas, prevents getting commas in the output (apologies for not using the lingo correctly). Here's my attempt:

use Parse::RecDescent;

my $grammar = q {
    varStatement:       'var' statements endofvar { $return = $item[2]
+ }
    statements:         <leftop: statement ',' statement>
    statement:          var_name (operator assignvalue)(?) { $return =
+ $item[1] }
    comma_values:       <leftop: assignvalue ',' assignvalue>

    assignvalue:        equality
                        | escapedRegex
                        | escapedQuote
                        | array_declaration
                        | numeric_value
                        | array_value
                        | object_value
                        | var_name

    array_declaration:  'new Array(' comma_values ')'
    array_value:        array_name '[' integer ']'

    equality:           '(' assignvalue equality_operator assignvalue 
+')'

    var_name:           /\w+/
    array_name:         /\w+/
    object_value:       /[A-Za-z0-9_.]+/

    numeric_value:      real_number | integer
    integer:            /\d+/
    real_number:        /\d+\.?\d*/

    escapedRegex:       '__REGEX__'
    escapedQuote:       '__QUOTE__'

    operator:           '='
    equality_operator:  '===' | '==' | '!='

    endofvar:           ';'
};

my @localDeclaredVars = <DATA>;
chomp @localDeclaredVars;

print "\n\n";
$parser = new Parse::RecDescent ($grammar) or die "*** Bad grammar!\n"
+;
foreach my $localDeclaredVar (@localDeclaredVars) {
  print "$localDeclaredVar\n";
  my $test = $parser->varStatement($localDeclaredVar) or print "*** Ba
+d text!!!\n";

  if ( ref($test) eq 'ARRAY' ) {
    print "==> ( @$test )\n";
  }
  else {
    print "==> $test\n";
  }
}

__END__
var myTest1 = 1;
var myTest2 = 2, myTest3 = 3, myTest4;
var myTest5 = new Array(__QUOTE__,__QUOTE__), myTest6;
var myTest7 =__REGEX__;
var myTest8 = myTest5.x;
var myTest9 = myTest[0], myTest10 = myTest[0];
var myTest11 = (myTest1 == myTest2);
var myTest12 = (myTest1 == myTest2), myTest13 = 2;
var myTest14 = (myTest1 == myTest2), myTest15;
var myTest16 = new Array(1, 2);
var myTest17, myTest18;
[download]

and here is the output:

var myTest1 = 1;
==> ( myTest1 )
var myTest2 = 2, myTest3 = 3, myTest4;
==> ( myTest2 myTest3 myTest4 )
var myTest5 = new Array(__QUOTE__,__QUOTE__), myTest6;
==> ( myTest5 myTest6 )
var myTest7 =__REGEX__;
==> ( myTest7 )
var myTest8 = myTest5.x;
==> ( myTest8 )
var myTest9 = myTest[0], myTest10 = myTest[0];
==> ( myTest9 myTest10 )
var myTest11 = (myTest1 == myTest2);
==> ( myTest11 )
var myTest12 = (myTest1 == myTest2), myTest13 = 2;
==> ( myTest12 myTest13 )
var myTest14 = (myTest1 == myTest2), myTest15;
==> ( myTest14 myTest15 )
var myTest16 = new Array(1, 2);
==> ( myTest16 )
var myTest17, myTest18;
==> ( myTest17 myTest18 )
[download]

This still misses array_names and variables within parenthesized expressions, but hey, it's a step in the right direction, I suppose. How would I be helping you if I solved your whole problem for you? :) At least you now have a debuggable chuknk of code.

dmm

Thank-you very much for leading me in the right direction... ++ to you. Just 2 days ago I didn't know anything about Parse:RecDescent... and now I wrote my first simple grammar to it... I don't know much about grammars, but I'm learning. That's why it's nice that someone can take a look at what I've done and give me pointers, etc.

One thing I haven't figured out, but now have some working code to play with, are the $return value 'stuff' (I was just guessing/hacking at it). Also, what you've done here does exactly what I want, return just the variable names (which I will use somewhere else in my code)... I'm not sure what you mean by missing "array_names" and "variables within parenthesized expressions", so I think I'll have a look into that as well.

I appreciate your time. What references do you use for this sort of thing? I've been reading the .pod files...

My pleasure. Actually, this is my first time using Parse::RecDescent, although I've written small grammars using bison. I didn't mean to actually solve your whole problem for you, just point you in the right direction.

By 'missing' I was referring to the fact that in the following output, myTest, myTest1 and myTest2 are not picked up:

var myTest9 = myTest[0], myTest10 = myTest[0];
==> ( myTest9 myTest10 )
var myTest11 = (myTest1 == myTest2);
==> ( myTest11 )
[download]