my @token = split ' ', $str;

for my $idx (reverse 0 .. $#token) {
    my $item = $token[$idx];
    $item =~ s/\.+$//;
    splice(@token, $idx, 1) if ! length($item);
}
my @structure;
for my $idx (grep {$_ % 2} 1 .. $#token) {
    push @structure, {
        chapter => $token{$idx - 1},
        name    => $toekn{$idx}
    };
}