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in reply to Re: Print contents of text file line by line
in thread Print contents of text file line by line

Thanks modperl...I see my mistake in trying to print the elements of an array without first declaring the array...
  • Comment on Re^2: Print contents of text file line by line

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Re^3: Print contents of text file line by line
by Anonymous Monk on Jun 24, 2018 at 23:47 UTC
    Unless you really want to print only selected lines of the file, you probably should use the line-by-line approach that you currently (unintentionally) wrote, and add a counter of the number of times this loop has executed, and end the loop after you have printed enough. This will work for any file regardless of size.
[reply]

      So I corrected my code and added this to create an array: my @line = <$fh>;

      how can I add an if statement to check if the 7th element of the array does exist?

      I've tried something like this but it did not work: 

       if ($line[6]){
print "Support Group: $line[6]";
}else
print "Support Group:UNKNOWN $line[6]";

      [download]

      Thanks,

[reply]
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        if the 7th element of the array does exist?

        You have to be pedantic if you are to be a programmer. The 7th element will always exist unless the array has fewer than 7 elements. But it might be undef or empty or whitespace, etc. so you need to be specific about what your condition to be evaluated is. This example checks for something other than whitespace:

        #!/usr/bin/env perl 
use strict;
use warnings;

my @line = <DATA>;
print "OMG, line 7 is missing/blank!!!\n" unless $line[6] =~ /\S/;

__DATA__
1
2
3
4
5
6

8
9

        [download]

        "It doesn't work" is as useful to a developer as "I'm ill" is to a medic. Try to be specific. SSCCE is best.

[reply]
[d/l]

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