Solution for task 2

1 files changed, 109 insertions, 0 deletions

diff --git a/challenge-072/bob-lied/perl/ch-2.pl b/challenge-072/bob-lied/perl/ch-2.pl
new file mode 100644
index 0000000000..e802c152cb
--- /dev/null
+++ b/challenge-072/bob-lied/perl/ch-2.pl
@@ -0,0 +1,109 @@
+#!/usr/bin/env perl
+# vim:set ts=4 sw=4 sts=4 et ai wm=0 nu:
+#=============================================================================
+# ch-2.pl
+#=============================================================================
+# Copyright (c) 2020, Bob Lied
+#=============================================================================
+# Perl Weekly Challenge 72 Task#2 Lines Range
+#=============================================================================
+# You are given a text file name $file and range $A - $B where $A <= $B.
+# Write a script to display lines range $A and $B in the given file.
+
+use strict;
+use warnings;
+use feature qw(say);
+
+use Getopt::Long;
+
+sub Usage { "Usage: $0 FILE A B\n\tA <= B" }
+
+
+sub runTests
+{
+    use Test::More;
+
+    my $TestResult;
+    my $dataStart =  tell DATA;
+    my $outfh;
+    open($outfh, ">", \$TestResult) || die "open TestResult: $!";
+
+    my $reInit = sub {
+        seek(DATA, $dataStart, 0);
+        $. = 0;
+        close($outfh);
+        open($outfh, ">", \$TestResult);
+    };
+
+        is( linesRange(*DATA, $outfh,  1,  1), 1, "first line");
+        close($outfh);
+        is( $TestResult, "L1\n", "check first line" );
+    $reInit->();
+        is( linesRange(*DATA, $outfh,  1,  4), 4, "head lines");
+        is( $TestResult, "L1\nL2\nL3\nL4\n", "check head lines" );
+    $reInit->();
+        is( linesRange(*DATA, $outfh,  9, 12), 4, "tail lines");
+        is( $TestResult, "L9\nL10\nL11\nL12\n", "check tail lines" );
+    $reInit->();
+        is( linesRange(*DATA, $outfh, 12, 12), 1, "last line");
+        is( $TestResult, "L12\n", "check last lines" );
+    $reInit->();
+        is( linesRange(*DATA, $outfh, 10, 15), 3, "past end");
+        is( $TestResult, "L10\nL11\nL12\n", "check past end lines" );
+    $reInit->();
+        is( linesRange(*DATA, $outfh, 15, 18), 0, "outside");
+        is( $TestResult, "", "check outside lines" );
+
+    done_testing;
+}
+
+my $doTest;
+GetOptions('test!' => \$doTest);
+
+
+my $infh;
+
+exit(!runTests()) if $doTest;
+
+die Usage unless scalar(@ARGV) == 3;
+
+my ($File, $A, $B) = @ARGV;
+
+die Usage . "\n$!" unless defined $File;
+die Usage unless defined $A && $A > 0;
+die Usage unless defined $B && $B >= $A;
+
+open($infh, "<", $File) || die Usage . "\n$1";
+
+linesRange($infh, *STDOUT, $A, $B);
+
+sub linesRange
+{
+    my ($infh, $outfh, $beg, $end) = @_;
+    my $count = 0;
+
+    while (<$infh>)
+    {
+        if ( $. >= $beg && $. <= $end )
+        {
+            print $outfh $_;
+            $count++;
+        }
+        last if $. > $end; # Don't read the whole thing uselessly
+    }
+    return $count;
+}
+
+__DATA__
+L1
+L2
+L3
+L4
+L5
+L6
+L7
+L8
+L9
+L10
+L11
+L12