Piers Cawley <[EMAIL PROTECTED]> writes:
> "TSa (Thomas Sandlaß)" <[EMAIL PROTECTED]> writes:
>
>> Piers Cawley wrote:
>>> My preference is for:
>>> Boo
>>> Boo
>>> Can't dereferene literal numeric literal 42 as a coderef.
>>
>> How do you reach the second 'Boo'? Iff -> does not create a Sub
>> but a Block instance then Luke's code can be interpreted as a
>> much smarter version of
>
> I really wish you'd quote in more detail, it makes it a real PITA to go back
> and find the explanatory code.
>
> sub foo () {
> return -> { return 42 }
> }
>
> my $code = foo();
> # ^--- continuations points to the RHS of the assignment
> say "Boo!";
> $code();
>
> So, this is what happens.
>
> 1. foo() returns a coderef to the RHS of the assignment.
> 2. The coderef gets assigned to $code.
> 3. say "Boo!"
> 4. We invoke the coderef, which returns 14 to continuation which was current
> when it was created.
> 5. That means 42 gets returned to the RHS of the assignment
> 6. say "Boo!"
> 7. Try to invoke the literal 42.
> 8. Die.
>
> In other words, it outputs:
>
> Foo
> Foo
> # dies
If that works, then I think it means we can write:
sub call-with-current-continuation(Code $code) {
my $cc = -> $retval { return $retval }
$code($cc);
}
Which I personally think is rather cute. Even if I can't quite bring myself to
believe it's that simple...
