Hi all,
I'm trying to implement a toy version of Basic using Parse::RecDescent as my first attempt at an interpreter. I can't figure out how to implement a goto. Damian Conway's provided plenty of documentation, and I've looked at merlyn's article... If someone could beat me over the head with the solution I would be most grateful.

Here's what I've got so far (edited to illustrate my problem): 
use Parse::RecDescent;

$RD_HINT++;
$RD_WARN++;
#$RD_TRACE++;

my $grammar = q{
  Start: Expression(s) /\Z/
  Expression: LineNum Print
      | LineNum Goto
      | <error>
  Print: /print/i /\"/ /[\s\w]+/ /\"/
  { 
      print "$item[3]\n";
  }
  Goto: /goto/i LineNum
  {
      print "Seen a goto line $item[2]\n";
      # How do I seek back to line $item[2] of
      # the input?
  }
  LineNum: /\d+/
  };

my $parser = new Parse::RecDescent($grammar);

undef $/;
my $text = <>;

$parser->Start($text);

[download]

Thanks in advance.

In reply to Goto with Parse::RecDescent by bent

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