# Latest **URL:** https://racket.discourse.group/latest.md?page=65 [Latest](https://racket.discourse.group/latest.md) · [Categories](https://racket.discourse.group/categories.md) · [Tags](https://racket.discourse.group/tags.md) **Page:** 66 --- ## [Suggestion: track if your modules have been installed from pkg server](https://racket.discourse.group/t/suggestion-track-if-your-modules-have-been-installed-from-pkg-server/675)
**Author:** [@dstorrs](https://racket.discourse.group/u/dstorrs)\ **Replies:** 3\ **Last updated:** [February 12, 2022, 12:10am UTC](https://racket.discourse.group/t/suggestion-track-if-your-modules-have-been-installed-from-pkg-server/675 "2022-02-12T00:10:28Z")
I often find myself wondering if the packages I've posted are in use by anyone. In part for the egoboo but also because if they aren't in use by anyone else then backwards compatibility isn't as important a consideratio… --- ## [How to use racket-raylib-2d on Windows 10](https://racket.discourse.group/t/how-to-use-racket-raylib-2d-on-windows-10/684)
**Author:** [@Decabytes](https://racket.discourse.group/u/Decabytes)\ **Replies:** 0\ **Last updated:** [February 12, 2022, 12:55am UTC](https://racket.discourse.group/t/how-to-use-racket-raylib-2d-on-windows-10/684 "2022-02-12T00:55:39Z")
This has eluded me for a long time and I just figured it out so I'd like to share with other people. Go to Releases · raysan5/raylib · GitHub and scroll down to raylib v2.5.0 Download raylib-2.5.0-Win64-mingw.zip Open … --- ## [How to package non-racket files into racket binary](https://racket.discourse.group/t/how-to-package-non-racket-files-into-racket-binary/667)
**Author:** [@dannypsnl](https://racket.discourse.group/u/dannypsnl)\ **Replies:** 7\ **Last updated:** [February 11, 2022, 5:26pm UTC](https://racket.discourse.group/t/how-to-package-non-racket-files-into-racket-binary/667 "2022-02-11T17:26:08Z")
The problem I actually facing is I write a compiler in Racket but the runtime is written in C, I write (parameterize (\[current-directory "./runtime"\]) (match-define (list stdout stdin status stderr do) (proces… --- ## [Some questions about stateless web-server](https://racket.discourse.group/t/some-questions-about-stateless-web-server/678)
**Author:** [@Hanson](https://racket.discourse.group/u/Hanson)\ **Replies:** 2\ **Last updated:** [February 11, 2022, 2:36pm UTC](https://racket.discourse.group/t/some-questions-about-stateless-web-server/678 "2022-02-11T14:36:08Z")
I am really confused about the stateless web-server. What's the diffrence between a (serve/servlet start #:stateless? #t) and a (require web-server) version of stateless server? With a stateful server, the url has … --- ## [Haskell-inspired define-where macro](https://racket.discourse.group/t/haskell-inspired-define-where-macro/672)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 0\ **Last updated:** [February 10, 2022, 2:21pm UTC](https://racket.discourse.group/t/haskell-inspired-define-where-macro/672 "2022-02-10T14:21:29Z")
Here's a little Haskell-inspired macro I whipped up for define: #lang racket (require (only-in racket/base \[define def\])) (require syntax/parse/define) (define-syntax-parser define \[(\_ head e:expr #:where body:expr… --- ## [Racket v8.4 Released](https://racket.discourse.group/t/racket-v8-4-released/671)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 1\ **Last updated:** [February 10, 2022, 1:21am UTC](https://racket.discourse.group/t/racket-v8-4-released/671 "2022-02-10T01:21:23Z")
Racket version 8.4 is now available from https://download.racket-lang.org Command-line Racket provides a new expression editor by default for its read-eval-print loop (REPL). The new REPL is based on the Chez Scheme e… --- ## [Racket matching or exceeding Golang for Echo server performance](https://racket.discourse.group/t/racket-matching-or-exceeding-golang-for-echo-server-performance/660)
**Author:** [@pseud](https://racket.discourse.group/u/pseud)\ **Replies:** 1\ **Last updated:** [February 9, 2022, 1:53pm UTC](https://racket.discourse.group/t/racket-matching-or-exceeding-golang-for-echo-server-performance/660 "2022-02-09T13:53:10Z")
Hey. It's hard to find many performance comparisons outside of the benchmarks team game, so I thought this might be an interesting data point. I was stumbling around, writing a TCP-based echo server, only later coming a… --- ## [Does custodian-shutdown-all block until threads are suspended/killed?](https://racket.discourse.group/t/does-custodian-shutdown-all-block-until-threads-are-suspended-killed/663)
**Author:** [@jjsimpso](https://racket.discourse.group/u/jjsimpso)\ **Replies:** 6\ **Last updated:** [February 8, 2022, 10:01pm UTC](https://racket.discourse.group/t/does-custodian-shutdown-all-block-until-threads-are-suspended-killed/663 "2022-02-08T22:01:13Z")
I have some code that is using custodian-shutdown-all in order to cancel an operation running in a previously spawned thread. I had made the assumption that custodian-shutdown-all would not return until the thread(s) it… --- ## [Question: namespace-require](https://racket.discourse.group/t/question-namespace-require/669)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 3\ **Last updated:** [February 8, 2022, 10:22am UTC](https://racket.discourse.group/t/question-namespace-require/669 "2022-02-08T10:22:11Z")
Hi This works: (let ((ns (make-base-namespace))) (parameterize ((current-namespace ns)) (namespace-require '(file "tests.rkt")))) This does not: (let ((ns (make-base-namespace))) (namespace-require '(file "tests.… --- ## [How to use mandatory arguments on the command line](https://racket.discourse.group/t/how-to-use-mandatory-arguments-on-the-command-line/655)
**Author:** [@dstorrs](https://racket.discourse.group/u/dstorrs)\ **Replies:** 7\ **Last updated:** [February 7, 2022, 4:30pm UTC](https://racket.discourse.group/t/how-to-use-mandatory-arguments-on-the-command-line/655 "2022-02-07T16:30:57Z")
I'm refreshing on 15.9 Command-Line Parsing and I note that there doesn't seem to be a way to say "this flag must be present." Am I missing something? Here's the normal workaround: #lang racket (define name (make-par… --- ## [Permission problem for scribble documentation when updating racket version on Ubuntu](https://racket.discourse.group/t/permission-problem-for-scribble-documentation-when-updating-racket-version-on-ubuntu/666)
**Author:** [@marc](https://racket.discourse.group/u/marc)\ **Replies:** 0\ **Last updated:** [February 7, 2022, 8:14am UTC](https://racket.discourse.group/t/permission-problem-for-scribble-documentation-when-updating-racket-version-on-ubuntu/666 "2022-02-07T08:14:47Z")
I have updated my version of Racket from 8.2 to 8.3 on Ubuntu 20.4 (Focal). While it works successfully, when I install new packages, I get the following error: open-output-file: error opening file path: /usr/share/ra… --- ## [Building with \`--enable-scheme\`](https://racket.discourse.group/t/building-with-enable-scheme/664)
**Author:** [@LiberalArtist](https://racket.discourse.group/u/LiberalArtist)\ **Replies:** 5\ **Last updated:** [February 7, 2022, 6:48am UTC](https://racket.discourse.group/t/building-with-enable-scheme/664 "2022-02-07T06:48:25Z")
I know how to build Racket from source and then use the copy of Chez Scheme built as part of the process, as discussed in Running chez after building Racket?. My case (as part of working on the Guix packaging of Racket) … --- ## [Umask - set default file permissions](https://racket.discourse.group/t/umask-set-default-file-permissions/613)
**Author:** [@winny](https://racket.discourse.group/u/winny)\ **Replies:** 10\ **Last updated:** [February 6, 2022, 6:54pm UTC](https://racket.discourse.group/t/umask-set-default-file-permissions/613 "2022-02-06T18:54:37Z")
Hey all, first post here on discourse :wave: ! I had a use-case to manipulate private, information-sensitive files in Racket, didn't find a way to set the umask so new directories/files have secure permissions (race-con… --- ## [Racket v8.4 release thread](https://racket.discourse.group/t/racket-v8-4-release-thread/510)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 16\ **Last updated:** [February 5, 2022, 7:49pm UTC](https://racket.discourse.group/t/racket-v8-4-release-thread/510 "2022-02-05T19:49:34Z")
The release process for v8.4 will begin in about a week. If you have any new features that you want in and are relatively close to to being done, now is a good time to do that. Upcoming dates: - 7th: Branch day, merge… --- ## [Question on new Racket install graphic IDE](https://racket.discourse.group/t/question-on-new-racket-install-graphic-ide/657)
**Author:** [@joekillian](https://racket.discourse.group/u/joekillian)\ **Replies:** 9\ **Last updated:** [February 5, 2022, 6:12pm UTC](https://racket.discourse.group/t/question-on-new-racket-install-graphic-ide/657 "2022-02-05T18:12:04Z")
Why in the code below getting "read-syntax: #lang not enabled" In the graphic IDE I get: "Welcome to DrRacket, version 8.3 \[cs\]. Language: Advanced Student; memory limit: 128 MB. read-syntax: #lang not enabled possi… --- ## [I think "state" of big-bang in 2htdp/universe does not work properly](https://racket.discourse.group/t/i-think-state-of-big-bang-in-2htdp-universe-does-not-work-properly/653)
**Author:** [@cametan](https://racket.discourse.group/u/cametan)\ **Replies:** 8\ **Last updated:** [February 5, 2022, 4:56pm UTC](https://racket.discourse.group/t/i-think-state-of-big-bang-in-2htdp-universe-does-not-work-properly/653 "2022-02-05T16:56:40Z")
I think "state" of big-bang in 2htdp/universe does not work properly. It seems the world struct should be widened to show its properties, or slots; however the size changer does not work at all on Linux version; there… --- ## [List of figures in scribble document](https://racket.discourse.group/t/list-of-figures-in-scribble-document/654)
**Author:** [@dominik.pantucek](https://racket.discourse.group/u/dominik.pantucek)\ **Replies:** 0\ **Last updated:** [February 4, 2022, 7:07pm UTC](https://racket.discourse.group/t/list-of-figures-in-scribble-document/654 "2022-02-04T19:07:26Z")
It is possible to use figures\[1\] from extra scribble libraries to show and reference figures within a scribble document. But I found no way of creating LaTeX-like list of figures. Something similar to table-of-contents\[2… --- ## [Vectors, boxes and places](https://racket.discourse.group/t/vectors-boxes-and-places/648)
**Author:** [@timjervis](https://racket.discourse.group/u/timjervis)\ **Replies:** 1\ **Last updated:** [February 4, 2022, 2:26pm UTC](https://racket.discourse.group/t/vectors-boxes-and-places/648 "2022-02-04T14:26:02Z")
Dear Racketeers, Is there something I have misunderstood about vectors, boxes and places which might explain why immutable boxes are not place-message-allowed, but immutable vectors are? \> (place-message-allowed? (box-… --- ## [When posting using mail, you can use markdown](https://racket.discourse.group/t/when-posting-using-mail-you-can-use-markdown/647)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 1\ **Last updated:** [February 3, 2022, 8:31pm UTC](https://racket.discourse.group/t/when-posting-using-mail-you-can-use-markdown/647 "2022-02-03T20:31:20Z")
For the many people who use email for posting, the forum handles your message as markdown. While you don’t need to use markdown, it has some helpful features: to format code start with three backticks () followed by s… --- ## [How to find the definition of functions?](https://racket.discourse.group/t/how-to-find-the-definition-of-functions/645)
**Author:** [@yuzeng](https://racket.discourse.group/u/yuzeng)\ **Replies:** 3\ **Last updated:** [February 3, 2022, 8:29pm UTC](https://racket.discourse.group/t/how-to-find-the-definition-of-functions/645 "2022-02-03T20:29:44Z")
Hi, I am a rookie to Racket. Recently I am debugging a Racket program, which depends on several other packages. I found it difficult to locate the definition for each function. The only way I know is using "trace". But t… --- ## [Racket:cant return input](https://racket.discourse.group/t/racket-cant-return-input/638)
**Author:** [@osman44](https://racket.discourse.group/u/osman44)\ **Replies:** 7\ **Last updated:** [February 1, 2022, 12:10am UTC](https://racket.discourse.group/t/racket-cant-return-input/638 "2022-02-01T00:10:29Z")
i have been asked to "Write a function with one argument, L, such that, if L is a number, then it is doubled and returned, otherwise it is returned unchanged" The problem iwhenever i run the function and say type in som… --- ## [R16 Web App - Community Code Evaluation](https://racket.discourse.group/t/r16-web-app-community-code-evaluation/636)
**Author:** [@Eutro](https://racket.discourse.group/u/Eutro)\ **Replies:** 1\ **Last updated:** [January 30, 2022, 4:54pm UTC](https://racket.discourse.group/t/r16-web-app-community-code-evaluation/636 "2022-01-30T16:54:25Z")
For people that don't know, R16 is originally a Discord bot for interactive, community-driven code evaluation. It saves snippets of code, which can then be recalled and executed on user-provided input. About six months … --- ## [Slightly different Discourse logo?](https://racket.discourse.group/t/slightly-different-discourse-logo/541)
**Author:** [@Laurent.O](https://racket.discourse.group/u/Laurent.O)\ **Replies:** 19\ **Last updated:** [January 29, 2022, 5:00pm UTC](https://racket.discourse.group/t/slightly-different-discourse-logo/541 "2022-01-29T17:00:20Z")
The current Discourse logo for Racket is exactly the same as the racket-lang.org one, so when I have the docs.racket-lang.org open, both tabs look the same (at least on Chrome), which makes it more difficult to switch to… --- ## [Single Sign-On across Racket- and non-Racket-based servers](https://racket.discourse.group/t/single-sign-on-across-racket-and-non-racket-based-servers/624)
**Author:** [@Byron](https://racket.discourse.group/u/Byron)\ **Replies:** 9\ **Last updated:** [January 28, 2022, 9:55am UTC](https://racket.discourse.group/t/single-sign-on-across-racket-and-non-racket-based-servers/624 "2022-01-28T09:55:14Z")
Any recommendations for implementing single sign-on across multiple (in my case two) Racket web servers and a Node server for a React-based UI? The user should be able to login on the main server (Racket) and select a R… --- ## [GUI for bash commands](https://racket.discourse.group/t/gui-for-bash-commands/628)
**Author:** [@JoePass](https://racket.discourse.group/u/JoePass)\ **Replies:** 4\ **Last updated:** [January 27, 2022, 10:45pm UTC](https://racket.discourse.group/t/gui-for-bash-commands/628 "2022-01-27T22:45:46Z")
Hi, I have a large collection of commands which I use in console bash to transform pdf, png, etc., like pdftk in.pdf cat 1 5 7 10-12 output out.pdf, for example, to extract specific pages from pdf file. I made some sh e… --- ## [How can I know the implicit name of a "World", defined in big-bang of 2htdp/universe?](https://racket.discourse.group/t/how-can-i-know-the-implicit-name-of-a-world-defined-in-big-bang-of-2htdp-universe/627)
**Author:** [@cametan](https://racket.discourse.group/u/cametan)\ **Replies:** 3\ **Last updated:** [January 26, 2022, 2:07pm UTC](https://racket.discourse.group/t/how-can-i-know-the-implicit-name-of-a-world-defined-in-big-bang-of-2htdp-universe/627 "2022-01-26T14:07:22Z")
Hello. I want to switch two images, according to the flag defined in a WorldState of big-bang in 2htdp/universe. Let's say, the experimental code I wrote was like this: #lang racket (require 2htdp/image 2htdp/univers… --- ## [Parser-tools output position token's position only has offset?](https://racket.discourse.group/t/parser-tools-output-position-tokens-position-only-has-offset/625)
**Author:** [@dannypsnl](https://racket.discourse.group/u/dannypsnl)\ **Replies:** 3\ **Last updated:** [January 26, 2022, 12:04pm UTC](https://racket.discourse.group/t/parser-tools-output-position-tokens-position-only-has-offset/625 "2022-01-26T12:04:24Z")
I want to parse some s-expression with position information by parser-tools (require parser-tools/lex (prefix-in : parser-tools/lex-sre)) (define-empty-tokens symbol (|(| |)|)) (define-tokens datum (ID … --- ## [Call for Participation: BOB 2022 (March 11, Berlin or online)](https://racket.discourse.group/t/call-for-participation-bob-2022-march-11-berlin-or-online/545)
**Author:** [@mike](https://racket.discourse.group/u/mike)\ **Replies:** 1\ **Last updated:** [January 25, 2022, 7:40am UTC](https://racket.discourse.group/t/call-for-participation-bob-2022-march-11-berlin-or-online/545 "2022-01-25T07:40:46Z")
Hope to see many Racketeers at BOB! Please take a minute to fill out our survey on onsite vs. online! BOB 2022 Conference “What happens if we simply use what’s best?” March 11, 2022, Berlin or online (0100+UTC) https://… --- ## [Box-and-whisker plot and updated violin plot](https://racket.discourse.group/t/box-and-whisker-plot-and-updated-violin-plot/622)
**Author:** [@alexh](https://racket.discourse.group/u/alexh)\ **Replies:** 0\ **Last updated:** [January 25, 2022, 12:59pm UTC](https://racket.discourse.group/t/box-and-whisker-plot-and-updated-violin-plot/622 "2022-01-25T12:59:52Z")
Hi Eveveryone, I added support for box-and-whisker plots to the plot package and made some updates to the violin renderers that were added recently by Cameron Moy. I put up a pull request with the changes, and if you h… --- ## [How do you select a dropdown option with marionette](https://racket.discourse.group/t/how-do-you-select-a-dropdown-option-with-marionette/621)
**Author:** [@badkins](https://racket.discourse.group/u/badkins)\ **Replies:** 1\ **Last updated:** [January 25, 2022, 1:21am UTC](https://racket.discourse.group/t/how-do-you-select-a-dropdown-option-with-marionette/621 "2022-01-25T01:21:27Z")
How do you select a dropdown option with marionette? In some cases, I've been successful by using element-type! to type the value, but that doesn't work in some cases. In particular, if there are key handling listeners … [Previous page](https://racket.discourse.group/latest.md?page=64) [Next page](https://racket.discourse.group/latest.md?page=66)