Hi folks,
I'm looking to read in a file, search for a particular string and then pring the nth line before the line containing the match. The code below which prints lines before and after the match are getting to where I want to be, but I'm looking for something cleaner/easier or other better approaches to this. Thanks in advance!
use strict;
use warnings;
use Tie::File;
sub max ($$) { $_[$_[0] < $_[1]] }
sub min ($$) { $_[$_[0] > $_[1]] }
my $file_in = 'data.txt';
my @lines;
tie @lines, 'Tie::File', $file_in or die "Unable to tie $file_in $!";
my $n_recs = @lines; # how many records are in the file?
my @lnbrs = ();
my $i = 0;
while ($i < $n_recs - 1) {
my $twolines = $lines[$i] . $lines[$i + 1];
if ($twolines =~ m/file\s+for\s+(?:bankrup|chapter)/im) {
push @lnbrs, $i
}
$i++;
}
foreach my $ln (@lnbrs) {
my $start = max($ln-3, 0);
my $end = min ($ln+3, $n_recs);
<strong class="highlight">print</strong> '-' x 75, "\n";
foreach ($start .. $end) {
<strong class="highlight">print</strong> "$lines[$_]\n";
}
}
untie @lines;
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