# Latest **URL:** https://racket.discourse.group/latest.md?page=32 [Latest](https://racket.discourse.group/latest.md) · [Categories](https://racket.discourse.group/categories.md) · [Tags](https://racket.discourse.group/tags.md) **Page:** 33 --- ## [Announcing The Little Learner: A Straight Line to Deep Learning](https://racket.discourse.group/t/announcing-the-little-learner-a-straight-line-to-deep-learning/1288)
**Author:** [@themetaschemer](https://racket.discourse.group/u/themetaschemer)\ **Replies:** 19\ **Last updated:** [March 11, 2024, 5:53pm UTC](https://racket.discourse.group/t/announcing-the-little-learner-a-straight-line-to-deep-learning/1288 "2024-03-11T17:53:30Z")
Daniel P. Friedman and I (Anurag Mendhekar) are pleased to announce that our upcoming book The Little Learner: A Straight Line to Deep Learning just got its release date, complete with a Preorder Sale (Barnes and Noble, … --- ## [How can I insert an image file into a Scribble document?](https://racket.discourse.group/t/how-can-i-insert-an-image-file-into-a-scribble-document/2779)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [March 11, 2024, 2:53pm UTC](https://racket.discourse.group/t/how-can-i-insert-an-image-file-into-a-scribble-document/2779 "2024-03-11T14:53:50Z")
Someone recently asked how can I insert a png image file into a Scribble document? The scribble manual gives a nice example of using a pict you create yourself: @; ---------------------------------------- @section\[#… --- ## [Zero-cost incompatible opaque types](https://racket.discourse.group/t/zero-cost-incompatible-opaque-types/2772)
**Author:** [@default.kramer](https://racket.discourse.group/u/default.kramer)\ **Replies:** 0\ **Last updated:** [March 9, 2024, 8:51pm UTC](https://racket.discourse.group/t/zero-cost-incompatible-opaque-types/2772 "2024-03-09T20:51:20Z")
Something I always wanted in Typed Racket was a way to create incompatible types which are actually the same underlying type. The idea is that maybe your application has a UserId type and a VendorId type which are both I… --- ## [Is there a set(e)uid function, or equivalent?](https://racket.discourse.group/t/is-there-a-set-e-uid-function-or-equivalent/2766)
**Author:** [@nxg](https://racket.discourse.group/u/nxg)\ **Replies:** 7\ **Last updated:** [March 9, 2024, 11:08am UTC](https://racket.discourse.group/t/is-there-a-set-e-uid-function-or-equivalent/2766 "2024-03-09T11:08:01Z")
Is there a way of changing (unix) user? I can see getpid in the racket/os package, and if a setuid-a-like function exists, I'd expect to find it nearby, but I can't find it there or under any other search string I can t… --- ## [Bug in flomat / block-diagonal?](https://racket.discourse.group/t/bug-in-flomat-block-diagonal/2767)
**Author:** [@timjervis](https://racket.discourse.group/u/timjervis)\ **Replies:** 4\ **Last updated:** [March 7, 2024, 11:55pm UTC](https://racket.discourse.group/t/bug-in-flomat-block-diagonal/2767 "2024-03-07T23:55:29Z")
Hi everyone, When I use flomat's block-diagonal function, I'm getting random instances of NaN in the result: #lang racket (require flomat) (define m (block-diagonal (eye 100) (eye 100))) (for\* (\[r (in-range (nrows… --- ## [How to check equality of \`values\`?](https://racket.discourse.group/t/how-to-check-equality-of-values/2758)
**Author:** [@xiaoyu2006](https://racket.discourse.group/u/xiaoyu2006)\ **Replies:** 13\ **Last updated:** [March 6, 2024, 12:47am UTC](https://racket.discourse.group/t/how-to-check-equality-of-values/2758 "2024-03-06T00:47:55Z")
The intuitive way doesn't work \> (equal? (values 1 2) (values 1 2)) result arity mismatch; expected number of values not received expected: 1 received: 2 \[,bt for context\] (P.S. Interestingly I failed to find a s… --- ## [Displaying the Editor of a Snip in Another Editor Canvas](https://racket.discourse.group/t/displaying-the-editor-of-a-snip-in-another-editor-canvas/2764)
**Author:** [@bakgatviooldoos](https://racket.discourse.group/u/bakgatviooldoos)\ **Replies:** 0\ **Last updated:** [March 5, 2024, 4:56pm UTC](https://racket.discourse.group/t/displaying-the-editor-of-a-snip-in-another-editor-canvas/2764 "2024-03-05T16:56:03Z")
Hi, Racket Discourse. I am busy playing around with editor-snips and I want to understand the interaction between editors, snips and displays. The particular case I am trying to understand, is getting the editor of an … --- ## [Pattern matching in racklog / datalog](https://racket.discourse.group/t/pattern-matching-in-racklog-datalog/2763)
**Author:** [@bremner](https://racket.discourse.group/u/bremner)\ **Replies:** 0\ **Last updated:** [March 5, 2024, 11:51am UTC](https://racket.discourse.group/t/pattern-matching-in-racklog-datalog/2763 "2024-03-05T11:51:58Z")
I was trying to port one of the prolog examples from plai 1 into racklog but it seems that the "#lang datalog"/"#lang racklog" rules for a clause head are stricter. So in particular rules like tc(plusE(L, R), numT) :-… --- ## [Terminal gets ruined after using charterm](https://racket.discourse.group/t/terminal-gets-ruined-after-using-charterm/2760)
**Author:** [@mskoh52](https://racket.discourse.group/u/mskoh52)\ **Replies:** 3\ **Last updated:** [March 3, 2024, 9:08pm UTC](https://racket.discourse.group/t/terminal-gets-ruined-after-using-charterm/2760 "2024-03-03T21:08:12Z")
I'm trying to use charterm to build a roguelike. I'm using iTerm2 with zsh on a mac. After exiting my racket program, terminal outputs every new line indented starting at the end of the previous line, like this: $ ls -1… --- ## [Evaluating file at runtime in Racket](https://racket.discourse.group/t/evaluating-file-at-runtime-in-racket/2718)
**Author:** [@xiaoyu2006](https://racket.discourse.group/u/xiaoyu2006)\ **Replies:** 2\ **Last updated:** [March 3, 2024, 1:19pm UTC](https://racket.discourse.group/t/evaluating-file-at-runtime-in-racket/2718 "2024-03-03T13:19:03Z")
This is originally a Stack Overflow post however issue A in the comment of the answer still persists. Thanks for any help in advance! =====Copy & Paste of the Stack Overflow Question===== I am making an application usi… --- ## [Quick Question: Fixing Bugs](https://racket.discourse.group/t/quick-question-fixing-bugs/2756)
**Author:** [@bakgatviooldoos](https://racket.discourse.group/u/bakgatviooldoos)\ **Replies:** 5\ **Last updated:** [March 2, 2024, 2:12pm UTC](https://racket.discourse.group/t/quick-question-fixing-bugs/2756 "2024-03-02T14:12:08Z")
Hi, Racket Discourse. I found a bug in the code for the append-editor-font-menu-items procedure from racket/gui. The functionality for making fonts smaller by one size is missing a negative sign. Compare the increment, … --- ## [Only-in in a require statement](https://racket.discourse.group/t/only-in-in-a-require-statement/2751)
**Author:** [@matteo-daddio](https://racket.discourse.group/u/matteo-daddio)\ **Replies:** 1\ **Last updated:** [February 29, 2024, 7:56pm UTC](https://racket.discourse.group/t/only-in-in-a-require-statement/2751 "2024-02-29T19:56:17Z")
Hello, using only-in in a require statement can improve the memory footprint? It’s a good practice? Matteo --- ## [Call for Participation: BOB 2024 (Berlin, March 15)](https://racket.discourse.group/t/call-for-participation-bob-2024-berlin-march-15/2591)
**Author:** [@mike](https://racket.discourse.group/u/mike)\ **Replies:** 2\ **Last updated:** [February 29, 2024, 2:45pm UTC](https://racket.discourse.group/t/call-for-participation-bob-2024-berlin-march-15/2591 "2024-02-29T14:45:57Z")
More info at https://bobkonf.de/2024/! ========================================================================= BOB 2024 Conference “What happens if we simply use what’s best?” March 1… --- ## [Compatibility of typed/racket and SRFI-42](https://racket.discourse.group/t/compatibility-of-typed-racket-and-srfi-42/2741)
**Author:** [@damien\_mattei](https://racket.discourse.group/u/damien_mattei)\ **Replies:** 31\ **Last updated:** [February 29, 2024, 1:55pm UTC](https://racket.discourse.group/t/compatibility-of-typed-racket-and-srfi-42/2741 "2024-02-29T13:55:04Z")
hello, both typed/racket and SRFI-42 "Eager comprehension" use the symbol : . This cause a simple program to fails, example: is there a way to use SRFI 42 with typed Racket ? Regards, Damien --- ## [Racket meet-up: Saturday, 2 March, 2024 at 18:00 UTC](https://racket.discourse.group/t/racket-meet-up-saturday-2-march-2024-at-18-00-utc/2753)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [February 29, 2024, 8:06am UTC](https://racket.discourse.group/t/racket-meet-up-saturday-2-march-2024-at-18-00-utc/2753 "2024-02-29T08:06:43Z")
Racket meet-up: Saturday, 2 March, 2024 at 18:00 UTC In your timezone: 2024-03-02T18:00:00Z (UTC). (converter) At this meet-up: Show and tell News & rumours AOB This meet-up will be held at https://meet.jit.si/Racket… --- ## [Unit test delayed forever](https://racket.discourse.group/t/unit-test-delayed-forever/2752)
**Author:** [@hendrikboom3](https://racket.discourse.group/u/hendrikboom3)\ **Replies:** 2\ **Last updated:** [February 28, 2024, 11:08pm UTC](https://racket.discourse.group/t/unit-test-delayed-forever/2752 "2024-02-28T23:08:19Z")
I have a program that, when run, builds some data structures, prints some diagnostic output, and then wait for an incoming http request on post 8080. I decided to try to use the Racket test facility to do the diagnostic… --- ## [Simple Login / Logout examples using web-server](https://racket.discourse.group/t/simple-login-logout-examples-using-web-server/2721)
**Author:** [@markshead](https://racket.discourse.group/u/markshead)\ **Replies:** 1\ **Last updated:** [February 27, 2024, 12:33pm UTC](https://racket.discourse.group/t/simple-login-logout-examples-using-web-server/2721 "2024-02-27T12:33:13Z")
I've been looking for simple examples of login and logout that user Racket's web-server. I've looked at Racket Stories and Koto. Are there any other simple examples I should look at? It doesn't have to be production leve… --- ## [Compiling macros?](https://racket.discourse.group/t/compiling-macros/2734)
**Author:** [@hendrikboom3](https://racket.discourse.group/u/hendrikboom3)\ **Replies:** 1\ **Last updated:** [February 26, 2024, 2:07pm UTC](https://racket.discourse.group/t/compiling-macros/2734 "2024-02-26T14:07:11Z")
Is it possible to compile macros to machine code? I mean compiling the macro itself rather than compiling the the code generated by the use of the macros. This might be useful to speed compilation of programs in domain… --- ## [Racket Implementation Details](https://racket.discourse.group/t/racket-implementation-details/2746)
**Author:** [@Rugged](https://racket.discourse.group/u/Rugged)\ **Replies:** 4\ **Last updated:** [February 26, 2024, 5:44am UTC](https://racket.discourse.group/t/racket-implementation-details/2746 "2024-02-26T05:44:09Z")
Hi, I want to make a racket implementation to learn about the implementation details, the software architecture , the components involved Language Oriented Programming Approach design decisions / trade offs made with … --- ## [Missing language in list](https://racket.discourse.group/t/missing-language-in-list/2744)
**Author:** [@hendrikboom3](https://racket.discourse.group/u/hendrikboom3)\ **Replies:** 0\ **Last updated:** [February 26, 2024, 3:57am UTC](https://racket.discourse.group/t/missing-language-in-list/2744 "2024-02-26T03:57:35Z")
The list of Racket languages in Racket should include scribble. --- ## [Awesome new subreddit does your Racket homework for you!](https://racket.discourse.group/t/awesome-new-subreddit-does-your-racket-homework-for-you/2743)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 0\ **Last updated:** [February 26, 2024, 2:56am UTC](https://racket.discourse.group/t/awesome-new-subreddit-does-your-racket-homework-for-you/2743 "2024-02-26T02:56:59Z")
Today I discovered this awesome subreddit: https://www.reddit.com/r/RacketHomeworks/ ... in which the user /u/mimety will do your homework for you! I'm thinking it could be really useful to build a large public databa… --- ## [How to make a file upload form and make the server handle it](https://racket.discourse.group/t/how-to-make-a-file-upload-form-and-make-the-server-handle-it/707)
**Author:** [@Hanson](https://racket.discourse.group/u/Hanson)\ **Replies:** 7\ **Last updated:** [February 25, 2024, 7:37pm UTC](https://racket.discourse.group/t/how-to-make-a-file-upload-form-and-make-the-server-handle-it/707 "2024-02-25T19:37:26Z")
How to make a file upload form and make the server handle it. I know how to create a upload form https://docs.racket-lang.org/web-server/formlets.html#%28def.\_%28%28lib.\_web-server%2Fformlets%2Finput..rkt%29.\_file-uploa… --- ## [Parallel HTTP Request Mutex Deadlock when Running from Dr Racket](https://racket.discourse.group/t/parallel-http-request-mutex-deadlock-when-running-from-dr-racket/2742)
**Author:** [@PastAghast](https://racket.discourse.group/u/PastAghast)\ **Replies:** 2\ **Last updated:** [February 25, 2024, 4:16pm UTC](https://racket.discourse.group/t/parallel-http-request-mutex-deadlock-when-running-from-dr-racket/2742 "2024-02-25T16:16:40Z")
I've been trying to write a Racket GUI tool that makes simultaneous HTTP requests across multiple threads and prints progress as it progresses. I decided to use a semaphore to avoid rate limiting and a mutex to manage th… --- ## [Windows 10 protected from Racket installation](https://racket.discourse.group/t/windows-10-protected-from-racket-installation/2738)
**Author:** [@jsampson45](https://racket.discourse.group/u/jsampson45)\ **Replies:** 1\ **Last updated:** [February 24, 2024, 1:45pm UTC](https://racket.discourse.group/t/windows-10-protected-from-racket-installation/2738 "2024-02-24T13:45:45Z")
When I double-click on racket-8.12-x86\_64-win32-cs.exe in Windows 10 I see the message "Windows protected your PC. Microsoft Defender SmartScreen prevented an unrecognised app from starting. Running this app might put yo… --- ## [Performance of Racket Pict Comparison](https://racket.discourse.group/t/performance-of-racket-pict-comparison/2735)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 0\ **Last updated:** [February 24, 2024, 2:27am UTC](https://racket.discourse.group/t/performance-of-racket-pict-comparison/2735 "2024-02-24T02:27:59Z")
https://benknoble.github.io/blog/2024/02/15/benchmarking-pict-equality/ I'm sharing this here partly for general discussion and partly because folks might be interested. I don't entirely understand the results, so I'm o… --- ## [How stable are #lang-based HtDP languages?](https://racket.discourse.group/t/how-stable-are-lang-based-htdp-languages/2727)
**Author:** [@shhyou](https://racket.discourse.group/u/shhyou)\ **Replies:** 3\ **Last updated:** [February 23, 2024, 6:27pm UTC](https://racket.discourse.group/t/how-stable-are-lang-based-htdp-languages/2727 "2024-02-23T18:27:28Z")
The class I'm TAing has been using menu-based teaching languages. I hope to have background expansion, blue boxes, the binding arrows and the Errortrace arrows available by default, so I wonder if #lang-based teaching l… --- ## [Some basic questions about macros and scope](https://racket.discourse.group/t/some-basic-questions-about-macros-and-scope/2731)
**Author:** [@neteroster](https://racket.discourse.group/u/neteroster)\ **Replies:** 3\ **Last updated:** [February 22, 2024, 11:31am UTC](https://racket.discourse.group/t/some-basic-questions-about-macros-and-scope/2731 "2024-02-22T11:31:32Z")
Recently, I have been reading Fear of Macros to understand some basic usage of macros in Racket. I found everything relatively easy to understand until I encountered the content related to lexical context. If my underst… --- ## [Handin server "ok" button minimizes whole DrRacket app?](https://racket.discourse.group/t/handin-server-ok-button-minimizes-whole-drracket-app/2732)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 1\ **Last updated:** [February 22, 2024, 2:20am UTC](https://racket.discourse.group/t/handin-server-ok-button-minimizes-whole-drracket-app/2732 "2024-02-22T02:20:02Z")
Several of the windows-using students in my class are reporting an irritating issue when using the handin server (DrRacket v8.11.1, Windows 11); specifically, when they click the "okay" button on the handin-server window… --- ## [TR check-equal does not catch errors?](https://racket.discourse.group/t/tr-check-equal-does-not-catch-errors/2719)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 6\ **Last updated:** [February 18, 2024, 6:20am UTC](https://racket.discourse.group/t/tr-check-equal-does-not-catch-errors/2719 "2024-02-18T06:20:29Z")
It appears to me that racket and typed/racket behave differently with respect to errors that occur during the evaluation of arguments to check-equal?. Specifically, the program #lang typed/racket (require typed/rackuni… --- ## [Why does my code run significantly faster on BC than CS?](https://racket.discourse.group/t/why-does-my-code-run-significantly-faster-on-bc-than-cs/2720)
**Author:** [@default.kramer](https://racket.discourse.group/u/default.kramer)\ **Replies:** 18\ **Last updated:** [February 17, 2024, 5:54pm UTC](https://racket.discourse.group/t/why-does-my-code-run-significantly-faster-on-bc-than-cs/2720 "2024-02-17T17:54:48Z")
I'm working on a NES emulator in Typed Racket and I've just gotten it complete enough to do some realistic performance testing. Racket 8.12 BC can run the emulator at 105 FPS, but the same code using 8.12 CS peaks at 45 … [Previous page](https://racket.discourse.group/latest.md?page=31) [Next page](https://racket.discourse.group/latest.md?page=33)