Two problems:

  • Missing space in <!--Start_of_revision-->
  • if rather than while

    A working version of your code in a form that is better for stand alone testing is:

    use strict;
use warnings;

my $text = join "", <DATA>;
while($text =~ /<!-- Start_of_revision-->(.*?)<!-- End_of_revision-->/
+sg)
    {
    print $1;
    }
    
__DATA__

<!-- Start_of_revision-->
revision1
<!-- End_of_revision-->

<!-- Start_of_revision-->
revision2
<!-- End_of_revision-->

<!-- Start_of_revision-->
revision3
<!-- End_of_revision-->

    [download]
    
revision1

revision2

revision3

    [download]
    Perl is Huffman encoded by design.

    In reply to Re: Regular expressions by GrandFather
    in thread Regular expressions by Anonymous Monk

    Title:
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