Re: [racket-users] Fast way to map over a list many times, changing ONE element each time?

Is there a split-at-reverse anywhere, equivalent to split-at except that the first return value is reversed? If not, should that be added somewhere like srfi/1? I’m asking because wanted to be able to write functions like: (define ((drop-lens n) lst) (define-values [fst-lst rst-lst] (split-at-

Re: [racket-users] Moving an image with the keyboard

Hi Patrick, The problem you’re up against is that in the code you’ve attached, we don’t have a clear picture of what the signatures for your functions are, nor of the “world” upon which big-bang operates. Standard practice in HtDP-based courses dictates that every big-bang program should have a

Re: [racket-users] TR typed-racket-more library docs

Thanks for volunteering! I think 2 is the correct approach here. Sam On Fri, Jun 26, 2015 at 8:58 PM, Jordan Johnson wrote: > Hi all, > > One thing I’ve noticed in working with Typed Racket is that some of the > libraries on the “Libraries Provided with Typed Racket” docs page have type > defini

[racket-users] TR typed-racket-more library docs

Hi all, One thing I’ve noticed in working with Typed Racket is that some of the libraries on the “Libraries Provided with Typed Racket ” docs page have type definitions that aren’t documented anywhere, but that

[racket-users] Moving an image with the keyboard

Dear All, I am not sure if this is the right place since I am working from the Realm of Racket book. If not, please let me know where I can take my question. I finished up chapter five, and wanted to modify the UFO example to move in relation to the arrow keys. Here is the code that I wrote: #

[racket-users] #true, #false, '()

Dear educators and users of our teaching languages, Dave Tompkins from Waterloo brought to our attention that I failed to properly warn about a change to the teaching languages of HtDP. Since the change may affect your teaching materials, we want -- to alert you now in case y