Whilst a good point, it would have been helpful to add that a character other than a pipe character could be substituted, thereby avoiding the problem whereby $foo comes with embedded pipe characters. In fact you could use a complex string which you feel is almost guaranteed not to occur!

e.g.

 my $sepstring = '7c6xb1%$#!@#$!@';

 my $foo = "Hello WorldFoo BarPerl MonksSlash Dot";
 for ($foo) {
    s/([a-z])([A-Z])/$1$sepstring$2/g;
    for (split /\Q$sepstring\E/ ) {
        print "$_ \n";
    }
 }
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