in reply to printing specific lines

i was perhaps thinking 
open (OUT, ">gout");

while (<>){
chomp;
$line = $_;
push @array, $line;
}

print @array;
open (IN, "<grep");

while (<IN>){

next unless $. == $array[$i++];
print OUT $_;
#if ($. == @array) {print OUT $_}
}

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Re^2: printing specific lines
by ambrus (Abbot) on Feb 27, 2005 at 22:54 UTC

    This code has a well-hidden bug (or maybe I'm too tired): you always increment $i even if the equalty doesn't stand. Change 

    next unless $. == $array[$i++];

    [download]
    to 
    next unless $. == $array[$i];
$i++;

    [download]
    and it should work.

    Also, you should really add or die "open: $! to your open statement.

    Update: and to eliminate a warning, you may want to replace 

    next unless $. == $array[$i++];
print OUT $_;

    [download]
    to 
    next unless $. == $array[$i];
print $_;
++$i < @array or last;

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