=over

=item $LAST_SUBMATCH_RESULT

=item $^N
X<$^N> X<$LAST_SUBMATCH_RESULT>

The text matched by the used group most-recently closed (i.e. the group
with the rightmost closing parenthesis) of the last successful match.
(See L</Scoping Rules of Regex Variables>).

This is subtly different from C<$+>. For example in

    "ab" =~ /^((.)(.))$/

we have

    $1,$^N   have the value "ab"
    $2       has  the value "a"
    $3,$+    have the value "b"

This is primarily used inside C<(?{...})> blocks for examining text
recently matched.  For example, to effectively capture text to a variable
(in addition to C<$1>, C<$2>, etc.), replace C<(...)> with

    (?:(...)(?{ $var = $^N }))

By setting and then using C<$var> in this way relieves you from having to
worry about exactly which numbered set of parentheses they are.

This variable is read-only, and its value is dynamically scoped.

This variable was added in Perl v5.8.0.

Mnemonic: the (possibly) Nested parenthesis that most recently closed.

=back