Who else spots the logic error in here?

Yes, and you don't break backwards compatiblity. Which is what AnonMonk was talking about.

If you use a menchanism like use $version or use feature there's no need to call it a major new version of perl. We already have these incremental language modifications in perl 5, which AnonMonk wished that Perl 6 would bring them.

That said, perl 5.10 still breaks backwards compatibility in several ways (introducing new operators, changed scoping of regex modifiers), even though it was "only" a bump in the minor version number. Even if it were possible in theory to avoid that, it would be a huge maintenance burden to ship two regex engines with different scoping rules, which are then swapped depending on the presence of a pragma.

I think Worthington++ started some strangely named project this autumn to link Perl 5 into Parrot, as an "equal" language. So evals and function/method calls should be doable, then. (Failed to google it right now.)

Edit: Thx, Audrey++

Blizkost perhaps? :)

See S01 for the answer.

S01 says "we sure wish so".

As for it actually happening..

Perl 6 has drastically different calling conventions than Perl 5, and even now has characters in its standard library functions that are prohibited in Perl 5 ("-"). The only way I see them inter-operating is through some hairy foreign function interface. Let's take this example from S01:

    use v6;
    # ...some Perl 6 code...
    {
        use v5;
        # ...some Perl 5 code...
        {
            use v6;
            # ...more Perl 6 code...
        }
    }
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How would this work with some real code dropped in:

    use v6;
    
    multi sub foo-bar(Str $a, Str $b) { "str/str" }
    multi sub foo-bar(Str $a, Int $b) { "str/int" }
    multi sub foo-bar(Str $a, Num $b) { "str/num" }
    multi sub foo-bar(Str $a, Array $b) { "str/num" }
    {
        use v5;
        # oh shit, what now? do I:
        foo-bar("1", "2"); # syntax error
        call_perl6_func("foo-bar", "1", "2"); # calls, but breaks sinc
+e Perl5 has no types
        # Maybe this instead:
        call_perl6_func("foo-bar", Perl6cast("Str", "1"), Perl6cast("S
+tr", "2");
        {
            use v6;
            # now how do I call perl 5?
        }
    }
[download]

That's just the simple case of calling a subroutine. How about the totally incompatible object systems?

Does someone have a plan for getting this working?