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POParse::RecDescent - getting information from it
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copied!<p>I'm working with the <a href="http://search.cpan.org/perldoc?Parse::RecDescent" rel="nofollow noreferrer">Parse::RecDescent</a> parser in Perl, and I seem to have the most terrible time getting information from it. The information readily available online does not seem to have non-trivial examples.</p> <p>Here is the code:</p> <pre><code>event_function: object_list ':' event_list ';' <defer: { #item is a special character with Parse::Recdescent. print Dumper($item{object_list}); $return = $item[1]; } > | object_list ':' ';' <defer: { print Dumper($item{object_list}); $return = $item[1]; } > </code></pre> <p>Here is the output</p> <pre><code>PS W:\developers\paulnathan\rd_dir> perl parser.pl testfile $VAR1 = 4; $VAR1 = 8; PS W:\developers\paulnathan\rd_dir> </code></pre> <p>The input file parses correctly.</p> <pre><code>stuff, stuff2: pre-operation event = {foo1, foo2}; </code></pre> <p>It <em>should</em> be outputting a hash keyed by "stuff", "stuff2".</p> <p>Thoughts?</p> <p>edit:</p> <pre><code>object_list : object ',' object_list <defer: { my $retval = (); $retval = ::merge_hash_refs($item[1], $item[3]); $return = $retval; } > | object <defer: { #print Dumper($item{object}); $return = $item{object}; } > object : '/' /[a-z0-9_][a-z0-9_]*/ '/' '...' <defer: { $::objects->{$item[2]} = "stuff"; $return = $::objects; } > | /[a-z0-9_][a-z0-9_]*/ <defer: { $::objects->{$item[1]} = "stuff"; $return = $::objects; } > </code></pre> <p>edit2: Merge_hash_refs, just in case. :-)</p> <pre><code>#takes two hash references. sub merge_hash_refs { my($ref1, $ref2) = @_; my $retref = (); while( my ($k, $v) = each %$ref1 ) { $retref->{$k} = $v; } while( my ($k, $v) = each %$ref2 ) { $retref->{$k} = $v; } return $retref; } </code></pre>

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