Jon Lang dataweaver-at-gmail.com |Perl 6| wrote:
>From S09, under Junctions:
"The exact semantics of autothreading with respect to control
structures are subject to change over time; it is therefore erroneous
to pass junctions to any control construct that is not implemented via
as a normal single or multi dispatch. In particular, threading
junctions through conditionals correctly could involve continuations,
which are almost but not quite mandated in Perl 6.0.0."
What is a continuation?
<http://en.wikipedia.org/wiki/Continuation>
Early on, Perl 6 discussion featured a lot on Continuations. Now, I
don't see it anywhere at all, and believe that the general form is not
required, by design. That is, "not mandated". It's a computer science
concept that generalizes *all* forms of flow control including
exceptions, co-routines, etc. The long-jump or exception is a more
normal case of returning to something that is still in context, but
imagine if you could go both ways: bookmark something in the code, like
making a closure but for the complete calling stack of activation
complexes, and then jump back to it later.