Trying to learn how to use Parse::RecDescent I thought I'd pick something simple - parse (and graph) boolean expressions. So far I have:
        my $grammar = q {
            { my $g = GraphViz->new }
            start: expression /$/ { $return = $g }
            expression: item_right_exp | right_exp | item
            right_exp: operator expression {$return = $g->add_node($it
+em[1]);$g->add_edge($return, $item[2]);}
            item_right_exp: item operator expression {$return = $g->ad
+d_node($item[1].'-'.$item[2].'-'.$item[3], label => $item[2]);$g->add
+_edge($return, $item[1]);$g->add_edge($return, $item[3]);}
            operator: 'AND' | 'OR'
            item: 'NOT' item | multi_word | word {$return = $g->add_no
+de($item[1]);}
            multi_word: '"'word(s)'"' {$return = join(' ', @{$item[2]}
+); }
            word: /[a-zA-Z\?\*]+/
            
        };

[download]
Is this kinda going in the right direction? The next step would be to add parenthesis and I am at a bit of a loss as to how to do that.

As I am very new at this any advice greatly appreciated.

In reply to Parse::RecDescent and boolean expressions by glwtta

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