Please forgive my ignorance - I'm a bit rusty. I am using regex to parse a data file. I am taking an exclusion approach (i.e., removing lines I don't want), but no matter what I do, the output contains blank lines for the lines excluded. I have tried chomp (which gets rid of all eol, which I don't want) and trimming (both commented out below), but to no avail. My exclusion criteria is working, but that may be part of the problem. Here's the code:

use strict;
use diagnostics;
use warnings;

# Define label variable

my $build = $ARGV[0];

die "\nScript aborted. Study code is missing as an argument.\n\nUsage:
+ $0 {STUDYCODE}\n" if @ARGV == 0;
      
open (LABELS, 'labels.txt') || die "Can't open labels.txt \n$!\n";
while (<LABELS>)
    {
    my $data_line = $_;
    # 
    if ($data_line =~ /$build/)
        {
        # Remove lines beginning with "bl", "BL" or "_" and releases w
+ith a label with xx.yy.zzz.nnn(n)
        $data_line =~ s/^[BbLl].*|^_.*|^.*\d\d\d\.\d\d\d.*//g;
        #chomp ($data_line); #Remove end of lines
        #$data_line =~ tr/\n//s; # Still have blank lines I need to re
+move
        print "$data_line";    
        }
    }
close LABELS;
exit;

[download]

Here is the input date I have in the file labels.txt: 

_STUDYABCD1234_1.00
_STUDYABCD1234_1.00.5678
STUDYABCD1234_1.00
STUDYABCD1234_1.00.000
p_STUDYABCD1234_1.00.000
p_STUDYABCD1234_1.00.000.5678
bl_STUDYABCD1234_1.00.000
bl_STUDYABCD1234_1.00.000.5678
BL_STUDYABCD1234_1.00.000
BL_STUDYABCD1234_1.00.000.5678

[download]

There are ten lines in the input file, and the output also contains 10 lines, three of which show properly, and 7 blank lines that are the excluded lines. Any help is appreciated. Thanks.

In reply to Remove blank lines from REGEX output by Deep_Plaid

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