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Re^5: How to print the lines immediately above and below a matching line?

by Anonymous Monk
on Nov 25, 2012 at 14:00 UTC ( #1005495=note: print w/ replies, xml ) Need Help??

Comment on Re^5: How to print the lines immediately above and below a matching line?
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Re^6: How to print the lines immediately above and below a matching line?
by Bio90 (Initiate) on Nov 25, 2012 at 14:09 UTC
    Here is the code with the change
    use strict; use warnings; open( my $fh, '<', 'input.txt') or die "Error opening file - $!\n"; open OUT, ">", "output.txt" or die "could not open output.txt $! \n"; my $this_line = ""; my $do_next = 0; my $data = <DATA>; while(<$fh>) { my $last_line = $this_line; $this_line = $_; chomp $data; if ($this_line =~ /\Q$data/) { print OUT $last_line unless $do_next; print OUT $this_line; $do_next = 1; } else { print OUT $this_line if $do_next; $last_line = ""; $do_next = 0; } } close ($fh); __DATA__ 4386_7#8 4350_7#6 4414_1#6

      Well, that will never issue that warning :) anyway this is what I imagine you're after, you can add lots of print/warn debugging statements to figure out how it works

      #!/usr/bin/perl -- #~ 2012-11-25-06:19:07PDT by Anonymous Monk #~ perltidy -olq -csc -csci=10 -cscl="sub : BEGIN END" -otr -opr -ce +-nibc -i=4 -pt=0 "-nsak=*" use strict; use warnings; use autodie; # dies if open/close... fail Main( @ARGV ); exit( 0 ); sub Main { if( @_ == 3 ) { NotDemoMeaningfulName( @_ ); } else { Demo(); print '#' x 33, "\n", Usage(); } } sub NotDemoMeaningfulName { my( $inputFile, $outputFile, $dataFile ) = @_; my $DataRegex = MakeRegex( $dataFile ); open my( $inFh ), '<', $inputFile; open my( $outFh ), '>', $outputFile; my $this_line = ""; my $do_next = 0; while( <$inFh> ) { my $last_line = $this_line; $this_line = $_; if( $this_line =~ m{$DataRegex} ) { print $outFh $last_line unless $do_next; print $outFh $this_line; $do_next = 1; } else { print $outFh $this_line if $do_next; $last_line = ""; $do_next = 0; } } close $inFh; close $outFh; } ## end sub NotDemoMeaningfulName sub Usage { <<"__USAGE__"; $0 $0 infile outfile datafile perl ${\__FILE__} perl ${\__FILE__} infile outfile datafile __USAGE__ } ## end sub Usage sub MakeRegex { my( $inputFile ) = @_; open my( $data ), '<', $inputFile; my @dForRex; while( <$data> ) { chomp; push @dForRex, quotemeta $_; } my $rex = join '|', @dForRex; qr{$rex}; } ## end sub MakeRegex sub Demo { my( $Input, $WantedOutput, $Data ) = DemoData(); NotDemoMeaningfulName( \$Input, \my $Output, \$Data ); require Test::More; Test::More::is( $Output, $WantedOutput, ' NotDemoMeaningfulName Works Aas Designed' ); Test::More::done_testing(); } sub DemoData { #~ http://perlmonks... my $One = <<'__One__'; 0 yes I am 1a Faking it :) 2b with a 4386_7#8 3c then a 4386_7#11 4 cause I go to 12 5a and thirteen too 6b shabba 4350_7#6 7c shabba shooby dooby doo 8 ha cha cha cha 9 hi hi hi __One__ #~ http://perlmonks... my $Two = <<'__Two__'; __Two__ #~ http://perlmonks... my $Three = <<'__Three__'; 4386_7#8 4350_7#6 4414_1#6 __Three__ return $One, $Two, $Three; } ## end sub DemoData __END__
        That's great, many thanks for your help!

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