Chomp in perl

sar123 has asked for the wisdom of the Perl Monks concerning the following question:

I have the following input file:


xabcd a1
+b1
+b2
+b3
+b4
+b5 abcd
xcdef c1
+d1
+d2
+d3
+d4
+cdef
[download]

I am trying to remove all the "+"signs and add the lines together to get output of the following type:


xabcd a1b1b2b3b4b5 abcd
xcdef c1d1d2d3d4cdef
[download]

Here is my code for this:

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

open my $fh, "<", "$ARGV[0]" or die "Could not open $!";

my @file = <$fh>;
$/ = "\n+";
chomp (@file);
print "@file\n";
[download]

But this gives the output same as the input file. What is wrong with code?

Comment on Chomp in perl Select or Download Code

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Re: Chomp in perl
by Athanasius (Archbishop) on Oct 05, 2014 at 06:12 UTC

Hello sar123,

You just need to move the line:

$/ = "\n+";
[download]

to before the line:

my @file = <$fh>;
[download]

so that the input record separator (which tells Perl what your “lines” are) is in effect when the file is read in. Then the script works as expected:

Read more... (742 Bytes)

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

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Re^2: Chomp in perl

by sar123 (Novice) on Oct 05, 2014 at 06:17 UTC

Thanks again...:)

[reply]

Re: Chomp in perl
by rnaeye (Friar) on Oct 05, 2014 at 16:23 UTC

#!/usr/bin/perl
use warnings;
use 5.16.2;

$/ = "\n+";
while (<DATA>) {
    if ($_ =~ m/\+/) {
            s/\n\+//;
    }
    print;
}
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Re^2: Chomp in perl

by rnaeye (Friar) on Oct 05, 2014 at 16:25 UTC

Added __DATA__

#!/usr/bin/perl
use warnings;
use 5.16.2;

$/ = "\n+";
while (<DATA>) {
    if ($_ =~ m/\+/) {
            s/\n\+//;
    }
    print;
}
say '';

__DATA__
xabcd a1
+b1
+b2
+b3
+b4
+b5 abcd
xcdef c1
+d1
+d2
+d3
+d4
+cdef
[download]

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