Clarification: This is not a question about reading one line at a time from a file or about using $/. I already have the entire string in a variable. The string can be thought of as a list of substrings ("paragraphs"). If I can detect the start of each substring ("paragraph"), how can I partition the string into a list which is exactly equivalent to the original string if I join the substrings back together?

Say you have a string like this in $_: 

abc:
  asdf1
  asdf2

def:
  asdf3

ghi:
  asdf4
  asdf5

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How would you write code to split this into a list of three paragraphs so that you get the original file back if you join the three paragraphs together? Assume you can use a line ending with : to recognize the start of a paragraph. I'm hoping there's simpler idiom than the one in the test program below: 
use strict;
use warnings;
$_ = <<EOF;
abc:
  asdf1
  asdf2

def:
  asdf3

ghi:
  asdf4
  asdf5
EOF
my @tmp  = split /^(\w+:)/m, $_, -1;
my $hdr  = shift @tmp;
my @list = ($hdr) if defined $hdr && $hdr ne "";
push @list, shift(@tmp) . shift(@tmp) while @tmp;
my $cnt = @list;
$" = "><";
print "cnt=$cnt, values=<@list>\n";

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In reply to How to split into paragraphs? by jrw

Title:
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