Re: [Factor-talk] Factor-talk Digest, Vol 109, Issue 8

[Hugh A. <hug...@ya...>]

Does that work if the quotation accesses the local variables?
Where are the local variables? Are they on the return-stack or in a heap block?
Why do you say '[ _ + ] rather than just [ + ] ?
thanks for your help --- Hugh




Do you mean something like this?

    : add-quot ( n -- quot ) '[ _ + ] ;

    { 1 2 3 } 10 add-quot map .

Yields:

{ 11 12 13 }

Note: this works in the listener with the non-optimizing compiler, but if
you tried to use this in compiled you'd need to add a static call effect to
the quot by either making ``add-quot`` inline, or currying it with ``[
call( x -- x ) ]``.




On Fri, Jul 10, 2015 at 8:09 PM, Hugh Aguilar <hug...@ya...>
wrote:

> Jul 9 at 8:19 PM
> I sent this yesterday but it seems to have gotten lost --- if it ends up
> being double-posted, I apologize.
>
> Can quotations in Factor still be executed after the parent function has
> gone out of scope (done its EXIT)? Scheme/Lisp allows this, and they hold
> the local frame of the parent function on the heap rather than on the stack
> so that it persists after the parent function has exited so the quotation
> can still use it. It has to eventually get GC'd. LOTD definitely doesn't
> have GC, because the FMITE is a micro-controller (also because we don't
> have tagged data so there is no way to tell the difference between an
> integer and a pointer except to know this a-priori).
>
> In LOTD I don't allow quotations to be executed after the parent function
> has gone out of scope; the parent function's local-frame is on the stack so
> it is lost when the parent function exits.
>
> In LOTD, a quotation could execute after the parent function has gone out
> of scope if it doesn't access the parent function's local variables --- but
> I disallow this too for consistency. The users should just use :NONAME for
> anonymous functions that persist indefinitely --- quotations are for
> situations where the anonymous function needs to communicate with the
> parent, and it does so either through local variables or (if a bar-feature
> higher-order function was used to call the quotation) on the data-stack.
>
> regards --- Hugh