# General **URL:** https://racket.discourse.group/c/general/12.md?page=4 [Latest](https://racket.discourse.group/latest.md) · [Categories](https://racket.discourse.group/categories.md) · [Tags](https://racket.discourse.group/tags.md) **Page:** 5 --- ## [12 days to RacketCon](https://racket.discourse.group/t/12-days-to-racketcon/3950)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [September 22, 2025, 7:45am UTC](https://racket.discourse.group/t/12-days-to-racketcon/3950 "2025-09-22T07:45:19Z")
12 days to RacketCon Join us to learn about miniDusa: An Extensible Finite-Choice Logic Programming Language Presentation details at https://con.racket-lang.org RacketCon is 4-5 October at UMass Boston and online. Reg… --- ## [An arrays proposal for R7RS Large](https://racket.discourse.group/t/an-arrays-proposal-for-r7rs-large/3947)
**Author:** [@Gambiteer](https://racket.discourse.group/u/Gambiteer)\ **Replies:** 0\ **Last updated:** [September 20, 2025, 4:36pm UTC](https://racket.discourse.group/t/an-arrays-proposal-for-r7rs-large/3947 "2025-09-20T16:36:00Z")
I'm preparing a proposal for programming with arrays, based largely on SRFI 231, for R7RS Large. SRFI 231 is here: This month I began discussing on the SRFI 231 mail list what changes to SRFI 231 might be necessary: … --- ## [Ion Fusion / 14 Days till RacketCon](https://racket.discourse.group/t/ion-fusion-14-days-till-racketcon/3945)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [September 19, 2025, 1:22pm UTC](https://racket.discourse.group/t/ion-fusion-14-days-till-racketcon/3945 "2025-09-19T13:22:21Z")
Only 14 days to go - have you registered yet? “Ion Fusion is a customizable programming language that unifies the semantics of persistent data and the code that manipulates it. Oriented around the Amazon Ion data forma… --- ## [16 Days till RacketCon](https://racket.discourse.group/t/16-days-till-racketcon/3943)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 1\ **Last updated:** [September 18, 2025, 10:02am UTC](https://racket.discourse.group/t/16-days-till-racketcon/3943 "2025-09-18T10:02:48Z")
16 Days till RacketCon Come join us and learn about Compositional Object Oriented Prototypes RacketCon programme and registration details at https://con.racket-lang.org You can see recordings of talks at previous even… --- ## [Oddities in branching structure](https://racket.discourse.group/t/oddities-in-branching-structure/3930)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 5\ **Last updated:** [September 16, 2025, 2:22pm UTC](https://racket.discourse.group/t/oddities-in-branching-structure/3930 "2025-09-16T14:22:43Z")
Ok, it's late, I'm tired, and I've spent a lot of time staring at git log --oneline --graph output, so forgive me if this is incoherent :slight\_smile: I (re?)discovered that git describe \ is generally not very h… --- ## [18 Days till RacketCon](https://racket.discourse.group/t/18-days-till-racketcon/3939)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [September 15, 2025, 8:26am UTC](https://racket.discourse.group/t/18-days-till-racketcon/3939 "2025-09-15T08:26:23Z")
It’s a great programme - details at https://con.racket-lang.org/ register now. (If you cannot attend in-person, there is an option to help support the livestream for remote participants.) S. :beetle: --- ## [\*\*Racket meet-up\*\*: Saturday, 6 September 2025 at 18:00 UTC](https://racket.discourse.group/t/racket-meet-up-saturday-6-september-2025-at-18-00-utc/3933)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [September 6, 2025, 5:54pm UTC](https://racket.discourse.group/t/racket-meet-up-saturday-6-september-2025-at-18-00-utc/3933 "2025-09-06T17:54:09Z")
Everyone is welcome to join us for the :racket: Racket meet-up: Saturday, 6 September 2025 at 18:00 UTC image by @pard In your timezone: 2025-09-06T18:00:00Z (UTC). (converter). At this meet-up: in-person meet-up… --- ## [Lock-free RO shared bytes w/o communicating across channels?](https://racket.discourse.group/t/lock-free-ro-shared-bytes-w-o-communicating-across-channels/3927)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 4\ **Last updated:** [September 3, 2025, 9:07pm UTC](https://racket.discourse.group/t/lock-free-ro-shared-bytes-w-o-communicating-across-channels/3927 "2025-09-03T21:07:23Z")
Like the title says, I'm looking for a way to efficiently share some data across embarrassingly parallel workloads without having to pay the communication cost of sending data through channels or locking it. I'm thinking… --- ## [Seeking custom \`#lang\`s for Resyntax](https://racket.discourse.group/t/seeking-custom-lang-s-for-resyntax/3922)
**Author:** [@notjack](https://racket.discourse.group/u/notjack)\ **Replies:** 0\ **Last updated:** [August 25, 2025, 11:08pm UTC](https://racket.discourse.group/t/seeking-custom-lang-s-for-resyntax/3922 "2025-08-25T23:08:54Z")
I've implemented experimental and rudimentary support in Resyntax for custom #langs, including non-s-expression #langs. This allows a language to configure Resyntax's default suggestions on code written in that language,… --- ## [FFI loading of raco-installed dynamic libraries](https://racket.discourse.group/t/ffi-loading-of-raco-installed-dynamic-libraries/3915)
**Author:** [@massung](https://racket.discourse.group/u/massung)\ **Replies:** 4\ **Last updated:** [August 20, 2025, 2:37pm UTC](https://racket.discourse.group/t/ffi-loading-of-raco-installed-dynamic-libraries/3915 "2025-08-20T14:37:46Z")
This might be better suited for "Internals", but being my first post to this forum... :wink: One particular issue that exists is that of being able to ffi-lib dynamic libraries that have been installed by raco. This is … --- ## [RacketCon tickets!](https://racket.discourse.group/t/racketcon-tickets/3902)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [August 14, 2025, 10:04pm UTC](https://racket.discourse.group/t/racketcon-tickets/3902 "2025-08-14T22:04:54Z")
(fifteenth RacketCon) October 4-5, 2025, UMass Boston To register, buy a ticket via Eventbrite. If you cannot attend in-person, there is an option to help support the livestream for remote participants. --- ## [Tab Style in DrRacket controlled by env var?](https://racket.discourse.group/t/tab-style-in-drracket-controlled-by-env-var/3899)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 5\ **Last updated:** [August 13, 2025, 3:07pm UTC](https://racket.discourse.group/t/tab-style-in-drracket-controlled-by-env-var/3899 "2025-08-13T15:07:38Z")
DrRacket has two different graphical tab styles for its editor windows. One looks like this: ... and the other looks like this: I have two related questions. The first is probably pretty simple: what controls thi… --- ## [RacketFest 2026 (Spring)](https://racket.discourse.group/t/racketfest-2026-spring/3838)
**Author:** [@dominik.pantucek](https://racket.discourse.group/u/dominik.pantucek)\ **Replies:** 4\ **Last updated:** [August 6, 2025, 12:48pm UTC](https://racket.discourse.group/t/racketfest-2026-spring/3838 "2025-08-06T12:48:53Z")
Hello fellow Racketeers, last RacketFest took place more than two years ago and I think it is time to Make Europe Great Again by organizing another one. It looks like we might be able to get a decent venue here in Pragu… --- ## [I can't seem to understand the output of the following code:](https://racket.discourse.group/t/i-cant-seem-to-understand-the-output-of-the-following-code/3886)
**Author:** [@Rugged](https://racket.discourse.group/u/Rugged)\ **Replies:** 3\ **Last updated:** [August 4, 2025, 10:50am UTC](https://racket.discourse.group/t/i-cant-seem-to-understand-the-output-of-the-following-code/3886 "2025-08-04T10:50:52Z")
\#lang racket ;; Use '() instead of the 'empty' alias (define board #("X" "0" empty empty)) (for/vector (\[val board\] #:when (empty? val)) val) ; this returns '#() I would expect it to return '#(empty emp… --- ## [New Discourse auto-formatting: Anyone else find this annoying?](https://racket.discourse.group/t/new-discourse-auto-formatting-anyone-else-find-this-annoying/3883)
**Author:** [@greghendershott](https://racket.discourse.group/u/greghendershott)\ **Replies:** 8\ **Last updated:** [August 3, 2025, 9:01pm UTC](https://racket.discourse.group/t/new-discourse-auto-formatting-anyone-else-find-this-annoying/3883 "2025-08-03T21:01:02Z")
The new Discourse UI here to compose a reply or post is pretty annoying, especially when using inline code via backticks. Try typing: \`module-\>namespace\` You get: module→namespace. Some auto-ligature thing kicks in. T… --- ## [Would it make sense to add a function for inverting a hash table to the standard library?](https://racket.discourse.group/t/would-it-make-sense-to-add-a-function-for-inverting-a-hash-table-to-the-standard-library/3869)
**Author:** [@ddrake](https://racket.discourse.group/u/ddrake)\ **Replies:** 8\ **Last updated:** [July 30, 2025, 12:24am UTC](https://racket.discourse.group/t/would-it-make-sense-to-add-a-function-for-inverting-a-hash-table-to-the-standard-library/3869 "2025-07-30T00:24:26Z")
If you have a hash table, there's a pretty reasonable "inverse" to that table: in the original, you have keys mapping to values. The obvious inverse would be a hash table whose keys are the values in the original table, … --- ## [Racket meet-up: Saturday, 2 August 2025](https://racket.discourse.group/t/racket-meet-up-saturday-2-august-2025/3872)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [July 25, 2025, 1:49pm UTC](https://racket.discourse.group/t/racket-meet-up-saturday-2-august-2025/3872 "2025-07-25T13:49:32Z")
Everyone is welcome to join us for the :racket: Racket meet-up: Saturday, 2 August 2025 at 18:00 UTC image by @pard In your timezone: 2025-08-02T18:00:00Z (UTC). (converter). At this meet-up: in-person meet-ups i… --- ## [Prelude Modules](https://racket.discourse.group/t/prelude-modules/3864)
**Author:** [@bakgatviooldoos](https://racket.discourse.group/u/bakgatviooldoos)\ **Replies:** 6\ **Last updated:** [July 22, 2025, 12:28pm UTC](https://racket.discourse.group/t/prelude-modules/3864 "2025-07-22T12:28:29Z")
Hi, Racket Discourse. I was reading @notjack's post about what they call prelude modules, and I find the term to be an interesting addition to the nomenclature, should it take hold. One can become friends with a named c… --- ## [Racket July Meet-up Boston Thursday, July 24 6:00pm](https://racket.discourse.group/t/racket-july-meet-up-boston-thursday-july-24-6-00pm/3863)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [July 20, 2025, 5:26pm UTC](https://racket.discourse.group/t/racket-july-meet-up-boston-thursday-july-24-6-00pm/3863 "2025-07-20T17:26:51Z")
Racket July Meet-up Boston Thursday, July 24 6:00pm Northeastern University West Village H Room 366 Come one come all ! Racket fans, racket fledglings, the racket-curious among us. Come to talk about racket with peo… --- ## [Whoa! Gift from students!](https://racket.discourse.group/t/whoa-gift-from-students/3778)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 4\ **Last updated:** [July 18, 2025, 9:40am UTC](https://racket.discourse.group/t/whoa-gift-from-students/3778 "2025-07-18T09:40:15Z")
Okay, this is hands-down the best gift I've ever gotten from students. --- ## [Handin with racket instead of teaching languages:](https://racket.discourse.group/t/handin-with-racket-instead-of-teaching-languages/3854)
**Author:** [@jestarray](https://racket.discourse.group/u/jestarray)\ **Replies:** 1\ **Last updated:** [July 16, 2025, 10:29am UTC](https://racket.discourse.group/t/handin-with-racket-instead-of-teaching-languages/3854 "2025-07-16T10:29:08Z")
(check: :language 'racket :requires '() :eval? #t :output (string-append (symbol-\>string ASSIGNMENT-NAME) ".rkt") :create-text? #t :textualize? #f ;;raises exception for submissio… --- ## [Map versus for/list (& idiomatic Racket, the "for/..." zoo, etc)](https://racket.discourse.group/t/map-versus-for-list-idiomatic-racket-the-for-zoo-etc/3831)
**Author:** [@ddrake](https://racket.discourse.group/u/ddrake)\ **Replies:** 12\ **Last updated:** [July 15, 2025, 6:07pm UTC](https://racket.discourse.group/t/map-versus-for-list-idiomatic-racket-the-for-zoo-etc/3831 "2025-07-15T18:07:55Z")
I'm learning Racket, and I do know about functional programming, and have used and loved map (and its relatives) in many languages (Haskell, emacs lisp, Typescript/JS, Python, Julia...even C#, where they call it Select..… --- ## [\*\*Racket meet-up\*\*: Saturday, 5 July 2025 at 18:00 UTC](https://racket.discourse.group/t/racket-meet-up-saturday-5-july-2025-at-18-00-utc/3832)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 3\ **Last updated:** [July 13, 2025, 11:50am UTC](https://racket.discourse.group/t/racket-meet-up-saturday-5-july-2025-at-18-00-utc/3832 "2025-07-13T11:50:09Z")
Everyone is welcome to join us for the :racket: Racket meet-up: Saturday, 5 July 2025 at 18:00 UTC In your timezone: 2025-07-05T18:00:00Z (UTC). (converter). At this meet-up: in-person meet-ups being planned for SF a… --- ## [Does anyone have a nix flake for racket and its lsp?](https://racket.discourse.group/t/does-anyone-have-a-nix-flake-for-racket-and-its-lsp/3849)
**Author:** [@nrs-status](https://racket.discourse.group/u/nrs-status)\ **Replies:** 1\ **Last updated:** [July 12, 2025, 4:04pm UTC](https://racket.discourse.group/t/does-anyone-have-a-nix-flake-for-racket-and-its-lsp/3849 "2025-07-12T16:04:38Z")
I'd like to run Racket on NixOS with neovim. I was wondering, does anyone have a working nix flake that will provide a shell with the lsp and the compiler? --- ## [Call for Papers: The 2025 Scheme and Functional Programming Workshop](https://racket.discourse.group/t/call-for-papers-the-2025-scheme-and-functional-programming-workshop/3847)
**Author:** [@youyoucong](https://racket.discourse.group/u/youyoucong)\ **Replies:** 0\ **Last updated:** [July 11, 2025, 11:00pm UTC](https://racket.discourse.group/t/call-for-papers-the-2025-scheme-and-functional-programming-workshop/3847 "2025-07-11T23:00:10Z")
CALL FOR PAPERS The 2025 Workshop on Scheme and Functional Programming Co-located with ICFP/SPLASH 2025 (Singapore) The 2025 Scheme and Functional Programming Workshop is calling for submissions. We invite high-qual… --- ## [A function that recursively copies files and directories](https://racket.discourse.group/t/a-function-that-recursively-copies-files-and-directories/3829)
**Author:** [@indrjo](https://racket.discourse.group/u/indrjo)\ **Replies:** 3\ **Last updated:** [July 7, 2025, 6:20pm UTC](https://racket.discourse.group/t/a-function-that-recursively-copies-files-and-directories/3829 "2025-07-07T18:20:17Z")
I know there is the function copy-directory/files, but I want a function that while descending directories performs some tasks before copying (see actions-on-dir). Here is the code I have written so far. #lang racket (… --- ## [Racket docker M1 Rosetta](https://racket.discourse.group/t/racket-docker-m1-rosetta/2947)
**Author:** [@jasonhemann](https://racket.discourse.group/u/jasonhemann)\ **Replies:** 7\ **Last updated:** [July 3, 2025, 11:00am UTC](https://racket.discourse.group/t/racket-docker-m1-rosetta/2947 "2025-07-03T11:00:36Z")
Thanks in advance. I'm having trouble w/racket specifically under docker emulating x86\_64. AFAIK everything else seems to be working fine. I saw @awiersdorf started a related discussion a while back. I'm seeing differ… --- ## [Proper usage of make-base-eval-factory](https://racket.discourse.group/t/proper-usage-of-make-base-eval-factory/3809)
**Author:** [@Laurent.O](https://racket.discourse.group/u/Laurent.O)\ **Replies:** 9\ **Last updated:** [July 2, 2025, 12:28am UTC](https://racket.discourse.group/t/proper-usage-of-make-base-eval-factory/3809 "2025-07-02T00:28:29Z")
Say I have a module my-pkg/foo.rkt which exports bar. The doc mypkg/scribblings/foo.scrbl uses scribble/example like: @(define (make-my-eval) (make-base-eval '(require "../foo.rkt"))) @examples\[#:eval (make-my-eval) b… --- ## [What to do about a crash in the #dtc animations language](https://racket.discourse.group/t/what-to-do-about-a-crash-in-the-dtc-animations-language/3810)
**Author:** [@ddrake](https://racket.discourse.group/u/ddrake)\ **Replies:** 4\ **Last updated:** [June 28, 2025, 7:04pm UTC](https://racket.discourse.group/t/what-to-do-about-a-crash-in-the-dtc-animations-language/3810 "2025-06-28T19:04:25Z")
I'm reading Don't Teach Coding Until You've Read This Book and working through some of the exercises there. Their code/languages are distributed with Dr. Racket, but the animations one crashes on my machine (Ubuntu 25.04… --- ## [High-level explanation of how the expander's event stream is structured](https://racket.discourse.group/t/high-level-explanation-of-how-the-expanders-event-stream-is-structured/3821)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 0\ **Last updated:** [June 27, 2025, 11:26pm UTC](https://racket.discourse.group/t/high-level-explanation-of-how-the-expanders-event-stream-is-structured/3821 "2025-06-27T23:26:42Z")
@notjack @mflatt @ryanc I'm attempting to give Resyntax more and better information from the macro expander, and to do so I'm taking a closer look at a lot of the log-expand events emitted by the expander. I'm aware of… [Previous page](https://racket.discourse.group/c/general/12.md?page=3) [Next page](https://racket.discourse.group/c/general/12.md?page=5)