You can also Tie the file to an array. This also has the advantage of being able to control memory usage and has a read cache.

Then all you need is a c-style for loop a $save scalar and a %done hash.

Similar to: 

my @array = qw/ foo bar baz blah bar blah baz/;

my $save = 0;
my %done;
for (my $x = 0; $x <= $#array; $x++) {
  $save = $x if ($array[$x] eq 'bar'  );
  print "X:$x SAVE:$save $array[$x]\n";
  if ( $array[$x] eq 'blah' and !defined($done{$x}) ) {
    $done{$x}++;
    $x = $save;
  }
}

[download]


grep
One dead unjugged rabbit fish later

In reply to Re: How do I backtrack while reading a file line-by-line? by grep
in thread How do I backtrack while reading a file line-by-line? by mdunnbass

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