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

$/=undef;
my $data = <DATA>;
my @text = ($data =~ /(Nullam.+(?:augue|libero)\.)/g);
print @text;

#__prints:
#Nullam quis augue.

##</code><code>##

$/=undef;
my $data = <DATA>;
my @text = ($data =~ /(Nullam\b[^.]+(?:augue|libero)\.)/g);
@text = map{tr/\n/ /;$_}@text;
print join("\n",@text),"\n";
#print join(" ",@text); #alternative to put a space after the period.