Re: [racket-users] HTDP2e Exercise 309

Thanks. I initially tried as below with first pattern [empty empty] and empty apparently is a variable that will match a non-empty list. I need to use '*()* (define (words-on-line llos) (match llos [*empty* empty] [(list a b ...) )) On Friday, 6 March 2020 04:01:46 UTC+7, Daniel

[racket-users] FFI, provide cstruct-out?

Hi all, Is there a way to provide all bindings generated by define-cstruct? Like (provide (struct-out foo)) but for C structs? Thanks! Peter -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving ema

Re: [racket-users] HTDP2e Exercise 309

Hint: (define (words-on-line llos) (match llos ['() empty] [(list a b ...) )) Dan -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+un

Re: [racket-users] "invalid memory reference" issue

I've pushed a repair for the development version of Racket CS. The problem was related to computing a hash code of an object (i.e., an instance of a class). If you need a workaround to keep using the released version of Racket CS, it may involve supplying explicit equality and hash-code functions

[racket-users] HTDP2e Exercise 309

Hey Guys, I do not see how to apply pattern matching to this problem. Using for/list as below makes the most sense to me and I do not see how to fit in pattern matching ; [List-of [List-of String]] -> [List-of Natural] ; produces list of number of Strings per item in a llos (check-expect (words

[racket-users] "invalid memory reference" issue

Hello, I have some code that uses my library, "remap". It previously used to work, but in Racket CS 7.6, it fails saying "invalid memory reference. Some debugging context lost". Clicking the crosses in DrRacket gives this backtrace: invalid memory reference. Some debugging context lost /home

Re: [racket-users] re-run really fast!

Some time ago (a lot more than a week), DrRacket started using the result of online expansion to run (look for the spiky green ball to know when it will work). It doesn't work in error trace mode tho. Could that be it? Robby On Thu, Mar 5, 2020 at 12:25 AM 'John Clements' via users-redirect < us

[racket-users] Issue with define-type and typed classes

So I have this file, found here: https://gitlab.com/hashimmm/remap/-/blob/3682db9fff3bc5007833e07bf9a9ed6e8e0170a9/private/tables.rkt Lines 51 through 55 say: (define-type (Func<%> A) (BaseFunc<%> A FuncAnyParam))(define-type BoolFunc<%> (Func<%> BooleanColumn))(define-type AnyFunc<%> (Func<%>