sub MySplit2 { 

    # args being like split but with the third INSTEAD a
    # preservation delimiter -- the OP requirement seems
    # to suggest that should be -1 for split anyway

    my $pat = shift;
    my $str = ( shift () || $_ );
    my $pat2 = shift; # a preservation delimiter
                      # i.e. not splits usual arg3
    my @return = ();
    my $inquotes = 0;

    for my $qs ( defined ( $pat2 )
                 ? ( split( /$pat2/, $str, -1 ) )
                 : ( $str ) ) {
        push @return, $inquotes
                      ? $qs
                      : split( /$pat/, $qs, -1 );
        $inquotes = !$inquotes;
    }
    return @return;
}