my $a: "ABCDEFGHI"
my $b: "<b>ABC</b>DEFGHI"

##</code><code>##

$a:
ABCD
EFGH
I
$b:
<b>A
BC</
b>DE
FGHI


##</code><code>##

$a:
ABCD
EFGH
I
$b:
<b>ABC</b>D
EFGH
I