Re: Weird behaviour with match-time code evaluation and backtracking

Use our instead of my and your code will work as you expect.

C:\test\DBMNested>p1
[0] Perl> sub getChecksum($) {
        my $in = shift;
        our $check = 0;
        $in =~ m/(?:(.)(?{$check += ord($1);}))*^/;
        return $check;
};;
print getChecksum( 'foo' );;
324

print getChecksum( 'foo' );;
324

print getChecksum( 'foobar' );;
633
[download]

Though its a very slow way to achieve your goal. Corion's unpack tip is the way to go.

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Comment on Re: Weird behaviour with match-time code evaluation and backtracking Download Code

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Re^2: Weird behaviour with match-time code evaluation and backtracking by ikegami (Patriarch) on Mar 05, 2008 at 09:42 UTC
That should be `local our $check;`. Let's not clobber our caller's variables. `sub getChecksum($) { my $in = shift; local our $check = 0; $in =~ m/(?:(.)(?{$check += ord($1);}))*^/; return $check;` [download]	[reply] [d/l] [select]