my %cache;
sub first_line
{
        my $filename = shift;
        return $cache{$filename} if exists $cache{$filename}
        open FILE,$filename or return "";
        my $line=<FILE>;
        $cache{$filename}=$line;
        return $line;
}

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Is this code correct? If so, how do we execute this program and how would we know that this code is doing caching activity?

janitored by ybiC: Retitle from less-than-descriptive "Hello Monks!!!!" to improve site search results

In reply to Cache Subroutine Return Value by souravdas

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