in reply to Ignoring lines in flat text file

if (length($line) >= 15 && substr($line, 14, 3) eq '801')

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or

if ($line =~ /^.{14}801/)

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Re^2: Ignoring lines in flat text file
by sheasbys (Initiate) on Sep 11, 2007 at 15:24 UTC
    Thanks for the advice. I have changed my strategy to have the look up ignore the line as is as along as it does not match the 4 options listed in the code below but I get a syntax error. As I am still a newbie I am not sure what is wrong with this snippet of code: 

    if ( $line !~ m/^2/ ) or
( substr($line, 14, 3) ne '800' ) or
( substr($line, 14, 3) ne '866' ) or
( substr($line, 14, 3) ne '877' ) or
( substr($line, 14, 3) ne '888' ) {

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    Thanks again.
[reply]
[d/l]

      The entire expression must be in parens.

      You also have logic errors. Your expression will always be true. 

      if (  $line !~ m/^2/
   || (  substr($line, 14, 3) ne '800'
      && substr($line, 14, 3) ne '866'
      && substr($line, 14, 3) ne '877'
      && substr($line, 14, 3) ne '888'
      )
   )
{
   ...
}

      [download]

      That could be simplified using a regexp or a lookup table 

      if (  $line !~ m/^2/
   || substr($line, 14, 3) !~ /^(?:800|866|877|888)\z/
   )
{
   ...
}

      [download]
      my %tollfree = map { $_ => 1 } 800, 866, 877, 888;

if (  $line !~ m/^2/
   || !$tollfree{ substr($line, 14, 3) }
   )
{
   ...
}

      [download]
[reply]
[d/l]
[select]
        When I use this code, without your suggestions, I preserve the contents of any line starting with a "2," which is desirable:

        if ( $line !~ m/^2/ ) {
.
.
.
else {
print OUTPUT $line . "\n";

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        My goal is to preserve any line starting with a 2 and write it to output as well as writing any line where positions 14-16 are not 800, 866, 877 or 888. While the logic appears sound to me it does not make sense why these lines are not written to the output.

        BTW I really appreciate your help.
[reply]
[d/l]
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