#!/usr/bin/perl -w 
use strict;

{
    local $/; 
    my $line = <DATA>;
    $line =~ s/\b\n\b/, /g;
    $line =~ s/\n{2,}/\n/g;
    print $line;
}

__DATA__
1,111
22,22
33,33

4,444
5,555
66,66



45,54
4,554
4,654
-----------

Output:
1,111, 22,22, 33,33
4,444, 5,555, 66,66
45,54, 4,554, 4,654

[download]

Well seen moritz !
Update:

#!/usr/bin/perl -w 
use strict;

{
    local $/; 
    my $line = <DATA>;
    $line =~ s/\n(?!\n)/, /g;
    $line =~ s/\n{2,}/\n/g;
    print $line;
}

__DATA__
!1,111
22,22?
.33,33//

4,444!!
::5,555
&&66,66



45,54@@
4,554<<
``4,654{

---
Output:
!1,111, 22,22?, .33,33//
, 4,444!!, ::5,555, &&66,66
, 45,54@@, 4,554<<, ``4,654{

[download]

hth,
PooLpi

'Ebry haffa hoe hab im tik a bush'. Jamaican proverb

In reply to Re: how to convert new line to "," by poolpi
in thread how to convert new line to "," by bh_perl

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