Re: Tie::File Write Problem

After you tied the file to the @lines array, you never make a modification to the @lines array. See Tie::File.

tie @lines, 'Tie::File', $file or die "No file found to work with.";
$lines[0] = 'foo';  # this should change the tied file
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Comment on Re: Tie::File Write Problem Download Code

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Re^2: Tie::File Write Problem by packetstormer (Monk) on Nov 17, 2011 at 19:32 UTC
That's my confusion, doesn't this line change the element in the line? `if($tmp[6] eq "6 Elm") {$tmp[6] = 'XXXXX'}` [download] I am splitting each line up based on the commas in the line and changing that element	[reply] [d/l]
Re^3: Tie::File Write Problem by toolic (Bishop) on Nov 17, 2011 at 19:57 UTC
That line does not change the @lines array or the tied file. That just changes the @tmp array. Tip #4 from Basic debugging checklist: `use Data::Dumper; print Dumper(\@tmp); print Dumper(\@lines);` [download]	[reply] [d/l]
Re^3: Tie::File Write Problem by jethro (Monsignor) on Nov 17, 2011 at 23:35 UTC
@tmp is a completely separate variable that is not tied to the file. The split copies the data. You would have to add the following inside the foreach-loop to change the file as you intented: `$i= join(',',@tmp);` [download] Note that even this works only because $i actually is an alias to the data in @lines and not a copy (this is magic done by the foreach loop)	[reply] [d/l]
Re^4: Tie::File Write Problem by packetstormer (Monk) on Nov 18, 2011 at 08:35 UTC
Thanks - when I think it through it makes sense as to why it wasn't writing to the file! Rejoining the value back into the line works perfectly!	[reply]