Re: [racket-dev] for/first and multiple values
On 8/29/10 8:33 PM, Carl Eastlund wrote: On Sun, Aug 29, 2010 at 8:32 PM, David Van Horn wrote: On 8/29/10 8:27 PM, Carl Eastlund wrote: What do you propose for/first should return if the set s is empty? #f? Which will do what in a 2-valued context? Blow up I suppose. I don't care; I'm not going to use for/first with an empty set. David _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] for/first and multiple values
On Sun, Aug 29, 2010 at 8:32 PM, David Van Horn wrote: > On 8/29/10 8:27 PM, Carl Eastlund wrote: >> >> What do you propose for/first should return if the set s is empty? > > #f? Which will do what in a 2-valued context? --Carl _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] for/first and multiple values
On 8/29/10 8:27 PM, Carl Eastlund wrote: What do you propose for/first should return if the set s is empty? #f? _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] for/first and multiple values
What do you propose for/first should return if the set s is empty? It will be somewhat difficult to make it divine that it ought to return two values. Perhaps, if this feature is adopted, for/first should allow a #:default keyword to specify the return value if no elements crop up, so you can put in the right number of values. Carl Eastlund On Sun, Aug 29, 2010 at 8:21 PM, David Van Horn wrote: > Why is the body of a for/first a single valued context? I would expect this > to work: > > (let ((s (set 1 3 10))) > (for/first ((x (in-set s))) > (values x (set-remove s x > > But I get: > > context expected 1 value, received 2 values: 1 (set 3 10) > > (By the way, this operation would be nice to have in racket/set.) > > David _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
[racket-dev] for/first and multiple values
Why is the body of a for/first a single valued context? I would expect this to work: (let ((s (set 1 3 10))) (for/first ((x (in-set s))) (values x (set-remove s x But I get: context expected 1 value, received 2 values: 1 (set 3 10) (By the way, this operation would be nice to have in racket/set.) David _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] printing images in REPL
I've added an index entry for 'configure-runtime now. Here's the relevant page (the last section): http://docs.racket-lang.org/reference/running-sa.html Robby On Sat, Aug 28, 2010 at 9:18 PM, Robby Findler wrote: > And sorry: here's a keyword: read-language. You'll want to set up your > language so that it can answer those queries. Then drracket will call > the info proc with 'configure-runtime. I could have sworn that was > documented somewhere, but I'm not finding it (I think that must be a > bug in searching or the entry got lost or something). In any case > drracket usees it like this: > > (let ([configs (get-info 'configure-runtime '())]) > (for ([config (in-list configs)]) > ((dynamic-require (vector-ref config 0) > (vector-ref config 1)) > (vector-ref config 2 > > where get-info comes from read-language. > > And yes, this is on my list to add to the guide-like docs in the tools manual. > > hth, > Robby > > On Sat, Aug 28, 2010 at 8:49 PM, Robby Findler > wrote: >> Did you forget what I explained at PLT day? You don't seem to be >> asking questions in terms of those things, so I'm not sure whether >> what I say is getting thru at all. >> >> Robby >> >> On Sat, Aug 28, 2010 at 8:47 PM, Shriram Krishnamurthi >> wrote: >>> ... which was my original question. But thanks. >>> >>> On Sat, Aug 28, 2010 at 9:36 PM, Robby Findler >>> wrote: I guess you don't have the print handler set up right. On Sat, Aug 28, 2010 at 8:23 PM, Shriram Krishnamurthi wrote: > The value I was returning is whatever kind of object is returned when > you embed an image in the Definitions window. That is, this was a > pasted, atomic image, not one created by a computation. I guess > they're not treated the same, but I'm surprised that ASL processing > the Definitions window didn't do the right conversion... > > On Thu, Aug 26, 2010 at 8:25 PM, Robby Findler > wrote: >> At the moment there is a barn-door sized security hole in DrRacket, >> whereby it will take any snip% instance from the user's program and >> just display it in the repl. You can exploit this for Good by making >> the current-print of your language turn some values into snips (like >> images and things). 2htdp/image already does this, so that should just >> work if you return those. Its hard to tell what value Shriram's >> program was returning tho. But if it is a bitmap% object, he just has >> to do >> >> (make-object image-snip% ...the-bitmap-goes-here...) >> >> We will close this hole at some point, when we have a reasonable way >> to allow people to add new kinds of values without the security >> breach. >> >> Robby >> >> On Thu, Aug 26, 2010 at 6:17 PM, Jay McCarthy >> wrote: >>> From what I can tell, it comes from ensuring that DrRacket shares the >>> htdp/image (or whatever) namespace with the running program so the >>> structs are the same and DrRacket's default renderer is detecting it. >>> I'm not sure how to replicate it though. (I tried for a bit so I could >>> make #lang frtime work.) >>> >>> Jay >>> >>> On Thu, Aug 26, 2010 at 11:55 AM, Shriram Krishnamurthi >>> wrote: What is the #lang magic that makes > (get-image-from-web "http://racket-lang.org/logo.png";) (instantiate (class ...) ...) show the image rather than just its constructor? Shriram _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev >>> >>> >>> >>> -- >>> Jay McCarthy >>> Assistant Professor / Brigham Young University >>> http://teammccarthy.org/jay >>> >>> "The glory of God is Intelligence" - D&C 93 >>> _ >>> For list-related administrative tasks: >>> http://lists.racket-lang.org/listinfo/dev >> > _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev >>> >> > _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] What happened to image=? in 2htdp/image
Oh, I see what happened: image=? is provided from lang/htdp-*, which I happened to not have not imported -- I was working in a Racket file that only imported 2htdp/image. And then I looked in the "Equality testing of images" section of the 2htdp/image documentation: http://docs.racket-lang.org/teachpack/2htdpimage.html#(part._.Equality_.Testing_of_.Images) and it didn't mention image=?, nor was it anywhere else on the page, while it does occur in the documentation of htdp/image: http://docs.racket-lang.org/teachpack/image.html#(def._((lib._htdp/image..rkt)._image~3d~3f)) So, yes, maybe image=? should be re-exported from 2htdp/image, or at least mentioned/linked to in the section about equality of images. --- nadeem On Sun, Aug 29, 2010 at 2:58 PM, Robby Findler wrote: > image=? seems to work okay to me. Is there some misleading > documentation or something somewhere that gives you the impression > that image=? doesn't work? > > Robby > > On Sun, Aug 29, 2010 at 12:58 PM, Nadeem Abdul Hamid wrote: >> Is the idea to use equal? to compare images? Wouldn't it be better to >> define image=? just for the sake of uniformity? >> >> --- nadeem >> _ >> For list-related administrative tasks: >> http://lists.racket-lang.org/listinfo/dev >> > _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] What happened to image=? in 2htdp/image
image=? seems to work okay to me. Is there some misleading documentation or something somewhere that gives you the impression that image=? doesn't work? Robby On Sun, Aug 29, 2010 at 12:58 PM, Nadeem Abdul Hamid wrote: > Is the idea to use equal? to compare images? Wouldn't it be better to > define image=? just for the sake of uniformity? > > --- nadeem > _ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/dev > _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
[racket-dev] What happened to image=? in 2htdp/image
Is the idea to use equal? to compare images? Wouldn't it be better to define image=? just for the sake of uniformity? --- nadeem _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] more space in GUI?
I've pushed a change that puts the check boxes between the radio boxes. See if you think that looks okay. Robby On Fri, Aug 27, 2010 at 12:34 PM, Shriram Krishnamurthi wrote: > The language chooser details panel looks like the attachment. It > looks like there are five Output Styles and Fraction Style combined, > rather than two distinct blocks of 3 and 2. A little spacing might > make it a bit easier to read. > > _ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/dev > _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
