gmane.comp.lang.racket.user

Re: gl2d / gl-world: Debugging strange error / determining which libraries are missing

JP Verkamp — 2012-05-17T23:04:22

Interesting. Taking away the gl-world code and using the code to
create a canvas% with a gl-context from here (
http://lists.racket-lang.org/users/archive/attachments/20100118/4272caa0/attachment-0001.ksh
) works just fine (albeit slowly, I need to get the OpenGL drivers
working correctly again).

Perhaps I'm using gl-world incorrectly. It would still be helpful if
there was a way to get a better error message to tell me what was
going wrong though.

On Thu, May 17, 2012 at 6:09 PM, JP Verkamp <racket< at >jverkamp.com> wrote:

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Re: gl2d / gl-world: Debugging strange error / determining which libraries are missing

JP Verkamp — 2012-05-17T22:09:34

For whatever reason I don't have that directory. I ran this version instead:
https://raw.github.com/plt/racket/master/collects/sgl/examples/gears.rkt

That worked fine, rotating the gears as expected and printing this to
the console:
RENDERER: Mesa DRI Intel(R) 945GM x86/MMX/SSE2
VERSION: 1.4 Mesa 8.0.2
VENDOR: Tungsten Graphics, Inc
EXTENSIONS: ...

If it helps, I'm using Ubuntu 12.04 which either didn't have Racket or
at least not a newer version, so I'm installing from this PPA:
deb http://ppa.launchpad.net/plt/racket/ubuntu precise main

On Thu, May 17, 2012 at 4:58 PM, Michael Wilber <mwilber< at >uccs.edu> wrote:

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Re: gl2d / gl-world: Debugging strange error / determiningwhich libraries are missing

Michael Wilber — 2012-05-17T20:58:24

Can you run other OpenGL Racket programs? For example, try the gears example:

racket /usr/lib/racket/collects/sgl/examples/gears.rkt

On Thu, 17 May 2012 17:49:21 -0400, JP Verkamp <racket-TWI4S2xZTlJWk0Htik3J/w< at >public.gmane.org> wrote:
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gl2d / gl-world: Debugging strange error / determining which libraries are missing

JP Verkamp — 2012-05-17T21:49:21

Hopefully someone out there can help me out, I've run into a a bit of
a problem with the gl2d and gl-world packages from PLaneT. I've got a
relatively small sample and whenever I run the code (even after
commenting out all of the OpenGL specific code other than the big-bang
call), I always get this error:

send: target is not an object: #f for method: call-as-current

The one relevant response I've found thus far on the subject is from
Matthew Flatt from last December on the mailing list (
http://lists.racket-lang.org/users/archive/2011-October/048813.html )
which says to check "Do you have "libgdkglext-x11-1.0" and
"libgtkglext-x11-1.0" installed?", which I do. There's a .so for each
in my /usr/lib directory. After that though, I'm not sure where to go.
Is there perhaps some way to check which libraries that Racket is
trying to load / what else might be causing the error?

Thanks,
JP
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Re: syntax-parse #:at

Jon Rafkind — 2012-05-17T20:52:07

Ok I see from the syntax/parse source that it uses lctx as the first argument to datum->syntax, so that mostly answers my question.

On 05/17/2012 02:41 PM, Jon Rafkind wrote:

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syntax-parse #:at

Jon Rafkind — 2012-05-17T20:41:06

What exactly are the semantics of #:at inside a #:literal-sets ([x #:at y]) ?

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Re: Uses of thunk*

Jay McCarthy — 2012-05-17T19:17:40

That function can't receive any keyword arguments.

Jay

On Wed, May 16, 2012 at 2:23 PM, Laurent <laurent.orseau< at >gmail.com> wrote:

Re: RedHat OpenShift

John Clements — 2012-05-17T18:54:33

On May 17, 2012, at 5:53 AM, Sam Tobin-Hochstadt wrote:


DItto. Followed instructions, got blank server running at

http://test-rackjbc.rhcloud.com

Neat!


Next step… understanding rhc.  

Well, I just figured one thing out, which is that you need to configure ~/.openshift/express.conf to contain the name of the key you provided to the web interface. Should I add this to the github wiki?

John Clements

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Re: Opengl racket 5.2.1

Matthew Flatt — 2012-05-17T15:04:42

You may need to install "gdkglext" and "gtkglext". See

  http://docs.racket-lang.org/gui/libs.html

for more information.

At Thu, 17 May 2012 11:56:39 -0300, Eduardo Bellani wrote:
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Opengl racket 5.2.1

Eduardo Bellani — 2012-05-17T14:56:39

Hello racket team.

For some fun, I have tried to play around with the opengl library
again. For starters I've tried to run the gears.rkt example.

This message popped up:

"There was an error initializing OpenGL. Maybe OpenGL is not supported
on the current platform."

From looking at the source I can tell that there is a problem with
the with-gl-context which means I guess that racket is failing to
find my opengl libs. Here is a report from ldconfig

ldconfig -p | grep -i libgl
        libglut.so.3 (libc6) => /usr/lib/libglut.so.3
        libglut.so (libc6) => /usr/lib/libglut.so
        libglibmm_generate_extra_defs-2.4.so.1 (libc6) =>
/usr/lib/libglibmm_generate_extra_defs-2.4.so.1
        libglibmm-2.4.so.1 (libc6) => /usr/lib/libglibmm-2.4.so.1
        libglib-2.0.so.0 (libc6) => /lib/i386-linux-gnu/libglib-2.0.so.0
        libglib-2.0.so (libc6) => /usr/lib/i386-linux-gnu/libglib-2.0.so
        libglapi.so.0 (libc6, OS ABI: Linux 2.4.20) =>
/usr/lib/i386-linux-gnu/libglapi.so.0
        libglade-2.0.s

Re: Help with simple macro

Vasishtha Spier — 2012-05-17T13:36:41

Thanks William.  Its not a for loop that I'm looking for, but rather a scope within which I have access to the sequence.  A typical case will be where I have two procedures within the scope that are recursive but also pass control to each other under certain conditions, and each of these procedures accesses the sequence.  


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Re: RedHat OpenShift

Sam Tobin-Hochstadt — 2012-05-17T12:53:47

Let me be the first to say that this is really cool!

On Wed, May 16, 2012 at 9:53 PM, Ray Racine <ray.racine-Re5JQEeQqe8AvxtiuMwx3w< at >public.gmane.org> wrote:

Re: Help with simple macro

William James — 2012-05-17T04:55:48

Can you instead simply use a for loop?
Something like

(for ([(x i) (in-indexed '("and" "so" "forth"))]
      #:when ((string-length x) . < . 4))
  (displayln (list x i)))


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Help with simple macro

Harry Spier — 2012-05-17T03:51:30

I'm trying to create a macro to simplify the syntax of having a local
scope with an indexed sequence generator.

Instead of entering this:
(let-values ([(more? get next) (sequence-generate (in-indexed SOME-SEQUENCE)])
       .... (get-next) ...(get-next).. etc. ))

I'd like to be able to enter this instead:
(with-sequence  SOME-SEQUENCE
. . . .. . (get-next) .
 . . . (get-next) . . . etc.)

I'm able to create a macro to do this
(with-sequence MORE? GET-NEXT SOME-SEQUENCE .........)
i.e.
(define-syntax-rule (with-indexed-sequence MORE? GET-NEXT SEQ BODY  ...)
     (let-values ([(MORE? GET-NEXT)(sequence-generate (in-indexed SEQ))])
       BODY ... ))

but I've been unable to create a macro to create this form:
---------------------------------------
(with-sequence  SOME-SEQUENCE
. . . .. . (get-next) .
 . . . (get-next) . . . etc.)
---------------------------------------

where I don't pass the names of the thunks to test for end of sequence
or to get the next item in the sequence, but that they are called
"m

Re: RedHat OpenShift

Ray Racine — 2012-05-17T02:10:51

One more thing of note.  Since the pre_build script is always run first in
the cycle, one can assume that racket is installed and working henceforth.
So the rest of RackOS system, scripts, and hooks such 'start', 'stop',
'deploy' etc.. can be written in Racket.  Putting together the Bash script
to bootstrap Racket was torture.  Should be easier now.


On Wed, May 16, 2012 at 9:53 PM, Ray Racine <ray.racine-Re5JQEeQqe8AvxtiuMwx3w< at >public.gmane.org> wrote:

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match-loop

William James — 2012-05-17T01:55:28

Another looping macro.

(define-syntax-rule (do-match-loop
    (sym ...) (pat ...) (lst ...) (expr ...))
  (let loop ((sym lst) ...)
    (when (andmap cons? (list sym ...))
      (match-let ((pat sym) ...)
        (call-with-values (lambda () expr ...) loop)))))

(define-syntax match-loop-aux
  (syntax-rules ()
    [(_ () (sym ...) pats lsts form)
     (do-match-loop (sym ...) pats lsts form)]
    [(_ (x x* ...) (sym ...) pats lsts form)
     (match-loop-aux (x* ...) (tmp sym ...) pats lsts form)]))

(define-syntax-rule (match-loop (pat lst) ... form)
  (match-loop-aux (pat ...) () (pat ...) (lst ...) form))


;; Testing:

(match-loop
  ((list a a* ...) '(2 3 4))
  ((displayln a)
   a*))

2
3
4


;; Early exit
(match-loop
  ((list a a* ...) '(3 5 8))
  ((if (odd? a)
     (begin (displayln a)
            a*)
     null)))

3
5


;; Destructuring
(match-loop
  (`((,a ,b) ,more ...) '((2 3) (8 9)))
  ((printf "~A -- ~A\n" a b)
   more))

2 -- 3
8 -- 9


;; Parallel
(match-loop
  ((list a a* ...) '(5 6 7))
  ((li

Re: RedHat OpenShift

Ray Racine — 2012-05-17T01:53:50

Quick update.

I have a rough and simple bootstrap working.

Here to see it running. http://test-rpr.rhcloud.com/
Read the README here about the DIY scripts.
https://github.com/RayRacine/rackos
Read here if you want to bring run Racket's default page on OpenShift.
https://github.com/RayRacine/rackos/wiki/Quick-Start

Basically OpenShift's DIY is a v0.1 of a lifecycle of shell script hooks
that are called whenever you push changes to your website/code via GIT to
OpenShift.

One of the hooks is the pre_build script (called when you push new code,
before the build script is called).
In pre_build, if Racket is NOT installed, Racket is auto downloaded rom
racket-lang.org, installed it and started on your cloud instance. At the
moment all you get is the default Racket WebServer home up and running.

See https://github.com/RayRacine/rackos/wiki/Quick-Start

Next step (not yet done) is to configure the Racket WebServer to servlet
code location to some distinguished directory in the repository structure.

Then you de

Re: Strange time function results

Robby Findler — 2012-05-17T00:55:53

DrRacket is doing a lot of work that can disrupt your attempts to time
things. To really isolate what is going on with some specific piece of
code, you are best off running the timings in 'racket' from the
command-line.

Robby

On Wed, May 16, 2012 at 3:22 PM, Harry Spier <vasishtha.spier< at >gmail.com> wrote:

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Re: Dialog with parent frame

Nick Shelley — 2012-05-16T22:50:27

I'd just like to say that I've always been impressed with the speed that
bugs are fixed. I realized after saying that I'd wait for the fix to be
pushed that, given what I've seen about how quick bug fixes have been
pushed in the past, it probably was already there. So I pulled the most
recent changes and, lo and behold, it was fixed and works great.

Thanks again.

On Wed, May 16, 2012 at 1:44 PM, Nick Shelley <nickmshelley-Re5JQEeQqe8AvxtiuMwx3w< at >public.gmane.org>wrote:

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Re: Problem scrolling contents of text% in editor-snip%

Kieron Hardy — 2012-05-16T22:40:30

Thanks for the info Matthew.

My misunderstanding of how the editor-snip% and text% classes work led me
to believe that it should be possible to scroll a message string displayed
within an editor-snip% and text% combination.

Eventually I gave up trying to make those work the way I wanted. After
reviewing the documentation, I changed my approach to the problem I had, to
wit, display and move (scroll) some text message within some area on a
pasteboard%. I post here the code from my working solution, along with a
little demonstration of its use, in case it might be useful for others.

If anyone knows of other solutions, or has suggestions to improve or
otherwise make my solution more idiomatic, please do let me know.

Cheers,

Kieron.

 ****

(module moving-text-snip racket/gui

  ; Define a sub-class of editor-snip% that has a pasteboard%,
  ;   which displays a string-snip% encapsulating the required text.
  ; start-moving-text creates a thread that moves the string-snip% across
the pasteboard%,
  ;   moving

Re: remote tasks

Eli Barzilay — 2012-05-16T21:22:30

Given the open tcp port, I think that you should add some comment next
to the disabled tests about it.



Well, you get some advantage with a complete graph, but IMO the
disadvantage of openning ports is a major one, since it makes this
something that is only useful on trusted LANs.



Is there a reason for not allowing it?



So I think that a note about the possibility of using zo binary data
would be a good addition.