[racket] TR - Syntax Entailing Syntax

The current (and only) use-case I have for this is embellishing expansion
with type annotations to assist with inferencing.  When the inferencing
improves this use-case vanishes.  The current example at hand is the
expansion of racket/place's (place ch body ...) - to roughly ->  (lambda
(ch) body ...) and with `ch' now as Any, where (lambda: ((ch :
Place-Channel)) body ...) would assist TR.  But I understand and agree with
avoid conditional code.




On Mon, Nov 5, 2012 at 3:43 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu>wrote:

> On Mon, Nov 5, 2012 at 3:28 PM, Ray Racine <ray.racine at gmail.com> wrote:
> > On syntax expansion.  Is there a way to determine in the macro whether
> I'm
> > expanding in a typed/racket environment vs regular racket.? Say for
> example
> > in place.rkt conditionally embellish the syntax templates with
> additional TR
> > annotations if the syntax is being expanded in TR vs R.
>
> Jay is correct about how to do this, but you shouldn't need to.  In
> particular, the TR annotations are all ignored by other tools, so it's
> safe to add them unconditionally.
>
> >
> > Thanks,
> >
> >
> > On Mon, Nov 5, 2012 at 3:14 PM, Ray Racine <ray.racine at gmail.com> wrote:
> >>
> >> OK, so it is a little bit of red herring on the unbound identifer
> >> `place?', i.e. there is an unexported identifier(s) in the expansion of
> >> `place?' which is the true issue.   For what it's worth is yet another
> level
> >> of syntax explosion below `place?'.  But if I get the full explosion
> graph
> >> of these these internal procedures situated into base-special-env.rkt it
> >> will all clear up is what I'm taking away.  A quick glance leads me to
> >> believe it is less than a dozen, which means doable in finite time.
> >>
> >> Time to saddle up and start charging them windmills.
> >>
> >> Thanks,
> >>
> >>
> >> On Mon, Nov 5, 2012 at 2:50 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu>
> >> wrote:
> >>>
> >>> On Mon, Nov 5, 2012 at 1:58 PM, Ray Racine <ray.racine at gmail.com>
> wrote:
> >>> > Consider the innocuous appearing snippit below from
> >>> > collects/racket/place/distributed/examples/hello-world.rkt
> >>> >
> >>> > #lang typed/racket
> >>> >
> >>> > (require racket/place/distributed
> >>> >          racket/place)
> >>> >
> >>> > (provide hello-world)
> >>> >
> >>> > (: hello-world (-> Place))
> >>> > (define (hello-world)
> >>> >   (place ch
> >>> >          (printf "hello-world received: ~a\n"
> >>> >                  (place-channel-get (assert ch place-channel?)))
> >>> >          (define HW "Hello World")
> >>> >          (place-channel-put (assert ch place-channel?) (format "~a\n"
> >>> > HW))
> >>> >          (printf "hello-world sent: ~a\n" HW)))
> >>> >
> >>> >
> >>> > First issue is:
> >>> > `place' is syntax entailing 2 closed over procs `place/proc' and
> >>> > `start-place defined in racket/place.  No prob. I know the secret
> >>> > incantation.
> >>> >
> >>> > So I add a couple of strawman typings base-special-env.rkt and these
> >>> > immediate undefined identifier errors magically go away.
> >>> >
> >>> >  ;; from the expansion of `place'
> >>> >   [(make-template-identifier 'place/proc 'racket/place)
> >>> >    (-> -Variable-Reference -Symbol -Symbol (-> -Symbol
> >>> > -Resolved-Module-Path
> >>> > -Symbol (-opt -Input-Port) (-opt -Output-Port) (-opt -Output-Port)
> >>> > -Place)
> >>> >        (-opt -Input-Port) (-opt -Output-Port) (-opt -Output-Port)
> >>> >        -Place)]
> >>> >   [(make-template-identifier 'start-place 'racket/place)
> >>> >    (-> -Symbol -Resolved-Module-Path -Symbol (-opt -Input-Port) (-opt
> >>> > -Output-Port) (-opt -Output-Port)
> >>> >        -Place)]
> >>> >
> >>> > The next one in the conga line is an unknown identifier error for
> >>> > `place?',
> >>> > which _is_ publicly exported by racket/place.  But `place?' is itself
> >>> > syntax, so I donno, we have some sort of require-syntax-for-syntax
> sort
> >>> > of
> >>> > thing going on.
> >>> >
> >>> > Just for laughs I tossed the below into base-special-env.rkt. and now
> >>> > hello-world.rkt has errors on duplicate definition of `place?'.
> >>> >  [(make-template-identifier 'place? 'racket/place)
> >>> >    (-> Univ -Boolean)]
> >>>
> >>> If `place?` is indeed exported by `racket/place`, then the above won't
> >>> work.  You'll need to give a type to the internal identifier that
> >>> `place?` expands into.
> >>>
> >>> However, looking at the expansion of the hello-world.rkt program, it
> >>> doesn't seem to contain `place?`.  So I'm confused as to where that's
> >>> coming from.
> >>>
> >>> Finally, the way the `place` form works means that it would be better
> >>> to give a type annotation to `ch` using the #{ch : Place} form.
> >>>
> >>> > Any ideas on how move forward?  The idea was to take a run at TRing
> the
> >>> > collects/racket/place/distributed/examples/hello-world.rkt
> >>> >
> >>> > Thanks in advance,
> >>> >
> >>> > Ray
> >>> >
> >>> >
> >>> > ____________________
> >>> >   Racket Users list:
> >>> >   http://lists.racket-lang.org/users
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>> sam th
> >>> samth at ccs.neu.edu
> >>
> >>
> >
>
>
>
> --
> sam th
> samth at ccs.neu.edu
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.racket-lang.org/users/archive/attachments/20121105/1923268a/attachment-0001.html>