# Questions & Answers **URL:** https://racket.discourse.group/c/questions/6.md?page=15 [Latest](https://racket.discourse.group/latest.md) · [Categories](https://racket.discourse.group/categories.md) · [Tags](https://racket.discourse.group/tags.md) **Page:** 16 --- ## [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 … --- ## [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… --- ## [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… --- ## [Scribble/manual: period after closing curly bracket gives problem](https://racket.discourse.group/t/scribble-manual-period-after-closing-curly-bracket-gives-problem/2725)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 5\ **Last updated:** [February 17, 2024, 2:45am UTC](https://racket.discourse.group/t/scribble-manual-period-after-closing-curly-bracket-gives-problem/2725 "2024-02-17T02:45:47Z")
\#lang scribble/manual @tt{a} . @;ok (mark the space before the period) @tt{a}. @;wrong\\ The wrong line works well when running the scrbl file locally, but installing from github with the package manager of DrRacket … --- ## [Procesor simulation in SICP](https://racket.discourse.group/t/procesor-simulation-in-sicp/2723)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 0\ **Last updated:** [February 15, 2024, 9:14pm UTC](https://racket.discourse.group/t/procesor-simulation-in-sicp/2723 "2024-02-15T21:14:39Z")
May be I have not read all, but it seems to me that the processor simulation described in SICP does not deal with the limited size of words (in registers and memory). I hope that I am wrong, but please tell me if yes or … --- ## [Vector-add function not available](https://racket.discourse.group/t/vector-add-function-not-available/2722)
**Author:** [@rvdalen](https://racket.discourse.group/u/rvdalen)\ **Replies:** 4\ **Last updated:** [February 15, 2024, 11:28am UTC](https://racket.discourse.group/t/vector-add-function-not-available/2722 "2024-02-15T11:28:49Z")
I want to add a single element at the end of a vector, but I cannot find a function like vector-add. I am assuming that is because it acts as a deterrent not to try and do this. Coming from a Clojure environment I am u… --- ## [Raco pkg install error: certificate verify failed](https://racket.discourse.group/t/raco-pkg-install-error-certificate-verify-failed/2717)
**Author:** [@Axel](https://racket.discourse.group/u/Axel)\ **Replies:** 7\ **Last updated:** [February 14, 2024, 10:08pm UTC](https://racket.discourse.group/t/raco-pkg-install-error-certificate-verify-failed/2717 "2024-02-14T22:08:20Z")
Hello, thank for the new version of Racket. I just managed to compile this new version and encountered a problem as I tried to install some packages via the package manager in drracket but that attempt failed. Than I … --- ## [Racket setup probrem on Windows](https://racket.discourse.group/t/racket-setup-probrem-on-windows/2714)
**Author:** [@atsushifx](https://racket.discourse.group/u/atsushifx)\ **Replies:** 1\ **Last updated:** [February 13, 2024, 2:02am UTC](https://racket.discourse.group/t/racket-setup-probrem-on-windows/2714 "2024-02-13T02:02:56Z")
I install Racket on Windows 11 and set Environment "PLTUSERHOME" and "PLTADDONDIR" for "XDG Base Directory" PLTUSERHOME = "C:\\Users\\atsushifx.config" PLTADDONDIR = "C:\\Users\\atsushifx.local\\share/Racket/addon" I want … --- ## [Racket server that controls some other components](https://racket.discourse.group/t/racket-server-that-controls-some-other-components/2707)
**Author:** [@Jerry\_A](https://racket.discourse.group/u/Jerry_A)\ **Replies:** 1\ **Last updated:** [February 7, 2024, 12:51pm UTC](https://racket.discourse.group/t/racket-server-that-controls-some-other-components/2707 "2024-02-07T12:51:47Z")
Hey everyone! I'm trying to create a simple website that would allow to control an Arduino light system with HTTP requests. For starters, I want to control a few lights with Arduino. Arduino is programmed to read the HTT… --- ## [Turning a list into values](https://racket.discourse.group/t/turning-a-list-into-values/2694)
**Author:** [@markshead](https://racket.discourse.group/u/markshead)\ **Replies:** 4\ **Last updated:** [February 6, 2024, 4:19am UTC](https://racket.discourse.group/t/turning-a-list-into-values/2694 "2024-02-06T04:19:53Z")
Is there a way to turn a list into values. So something like the magic function in this example: (define-values (name age) (magic '("Bob" 25))) --- ## [Putting a large pict in a text%: scroll bar problems](https://racket.discourse.group/t/putting-a-large-pict-in-a-text-scroll-bar-problems/2700)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 8\ **Last updated:** [February 6, 2024, 12:50am UTC](https://racket.discourse.group/t/putting-a-large-pict-in-a-text-scroll-bar-problems/2700 "2024-02-06T00:50:12Z")
To reproduce: raco pkg install https://github.com/benknoble/frosthaven-manager#rich-text-protocol racket -l frosthaven-manager/t (t for "test example" or some such) I get an explained pict and then a GUI Easy-bui… --- ## [Import a r6rs library from another r6rs library in the same directory?](https://racket.discourse.group/t/import-a-r6rs-library-from-another-r6rs-library-in-the-same-directory/2691)
**Author:** [@awwx](https://racket.discourse.group/u/awwx)\ **Replies:** 0\ **Last updated:** [January 30, 2024, 10:02pm UTC](https://racket.discourse.group/t/import-a-r6rs-library-from-another-r6rs-library-in-the-same-directory/2691 "2024-01-30T22:02:30Z")
I can easily require a r6rs library file in the same directory from a Racket program: a1.rkt: #lang racket (require "b2.rkt") (foo) a2.rkt: #!r6rs (library (a2) (export foo) (import (rnrs)) (define (foo) … --- ## [In the htdp book, how much leeway do we have with adjusting the templates?](https://racket.discourse.group/t/in-the-htdp-book-how-much-leeway-do-we-have-with-adjusting-the-templates/2683)
**Author:** [@candleconch](https://racket.discourse.group/u/candleconch)\ **Replies:** 6\ **Last updated:** [January 29, 2024, 7:08pm UTC](https://racket.discourse.group/t/in-the-htdp-book-how-much-leeway-do-we-have-with-adjusting-the-templates/2683 "2024-01-29T19:08:00Z")
Hi, everyone. First time posting here. A novice in programming. So I have this question which I've posted on stackoverflow - you can read the long version of it here: https://stackoverflow.com/q/77874527/22037671 One … --- ## [Best way to use Racket for app development?](https://racket.discourse.group/t/best-way-to-use-racket-for-app-development/2688)
**Author:** [@dstorrs](https://racket.discourse.group/u/dstorrs)\ **Replies:** 3\ **Last updated:** [January 29, 2024, 7:07pm UTC](https://racket.discourse.group/t/best-way-to-use-racket-for-app-development/2688 "2024-01-29T19:07:35Z")
I'd like to develop apps for the Google store (Android) and/or the Apple store (iOS). What is the best way to do that? I'm aware of GitHub - jeapostrophe/racket-android: deploying Racket on Android and some options for… --- ## [Racket for Hydroper Jet?](https://racket.discourse.group/t/racket-for-hydroper-jet/2667)
**Author:** [@matheus](https://racket.discourse.group/u/matheus)\ **Replies:** 2\ **Last updated:** [January 15, 2024, 5:55pm UTC](https://racket.discourse.group/t/racket-for-hydroper-jet/2667 "2024-01-15T17:55:11Z")
I've spent a little time formulating compilation units for the Hydroper Jet Language using the Rust language. However, I'm not sure whether it's worthy continuing ahead to build a handwritten parser. What I want to do i… --- ## [Double instantiation of modules from namespace-require in executable](https://racket.discourse.group/t/double-instantiation-of-modules-from-namespace-require-in-executable/2662)
**Author:** [@mthom](https://racket.discourse.group/u/mthom)\ **Replies:** 2\ **Last updated:** [January 13, 2024, 5:56pm UTC](https://racket.discourse.group/t/double-instantiation-of-modules-from-namespace-require-in-executable/2662 "2024-01-13T17:56:17Z")
After compiling my Racket application to an executable with raco, I'm finding that namespace-require re-instantiates several modules. Consequently, the namespace I'm trying to load into has its contents split across two … --- ## [Looking for a tutor](https://racket.discourse.group/t/looking-for-a-tutor/2656)
**Author:** [@Shasvi](https://racket.discourse.group/u/Shasvi)\ **Replies:** 4\ **Last updated:** [January 11, 2024, 10:54am UTC](https://racket.discourse.group/t/looking-for-a-tutor/2656 "2024-01-11T10:54:52Z")
I have an exam on DrRacket, but I'm not understanding nothing. Can someone help me, please? I have past paper with solutions thanks --- ## [Where to start with optimizing Racket programs?](https://racket.discourse.group/t/where-to-start-with-optimizing-racket-programs/2634)
**Author:** [@nikhilm](https://racket.discourse.group/u/nikhilm)\ **Replies:** 25\ **Last updated:** [January 9, 2024, 8:41pm UTC](https://racket.discourse.group/t/where-to-start-with-optimizing-racket-programs/2634 "2024-01-09T20:41:47Z")
Given a plain racket program like #lang racket/base (require racket/generator racket/unsafe/ops) (define (gen-primes-upto n) (generator () (if (= n 2) (void) (… --- ## [Possible acmart.cls update needed, for language scribble/acmart](https://racket.discourse.group/t/possible-acmart-cls-update-needed-for-language-scribble-acmart/2648)
**Author:** [@encomer](https://racket.discourse.group/u/encomer)\ **Replies:** 2\ **Last updated:** [January 9, 2024, 5:08pm UTC](https://racket.discourse.group/t/possible-acmart-cls-update-needed-for-language-scribble-acmart/2648 "2024-01-09T17:08:35Z")
When using the scribble/acmart language (for PDF output), an error is reported in the interaction window, saying that the hyperref package needs to be before the hyperxmp package. The error is solved when changing the r… --- ## [Computer shuts down randomly, racket project deleted](https://racket.discourse.group/t/computer-shuts-down-randomly-racket-project-deleted/2652)
**Author:** [@ninek190](https://racket.discourse.group/u/ninek190)\ **Replies:** 2\ **Last updated:** [January 8, 2024, 9:59am UTC](https://racket.discourse.group/t/computer-shuts-down-randomly-racket-project-deleted/2652 "2024-01-08T09:59:09Z")
Hello, I am writing a final project for a university course and my computer randomly shut down when I had DrRacket open. When I restarted the pc, I couldnt open the racket file and I received an error about backup file.… --- ## [Backup ("autosave") files?](https://racket.discourse.group/t/backup-autosave-files/2653)
**Author:** [@frodeaux](https://racket.discourse.group/u/frodeaux)\ **Replies:** 0\ **Last updated:** [January 7, 2024, 9:33pm UTC](https://racket.discourse.group/t/backup-autosave-files/2653 "2024-01-07T21:33:22Z")
Is it possible to configure DrRacket to put backup files into a directory other than the directory containing the source file? --- ## [Was there a bug embedding srcloc's in compiled code in BC 8.5 (that was resolved in roughly 8.9)?](https://racket.discourse.group/t/was-there-a-bug-embedding-srclocs-in-compiled-code-in-bc-8-5-that-was-resolved-in-roughly-8-9/2647)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 0\ **Last updated:** [January 5, 2024, 6:53pm UTC](https://racket.discourse.group/t/was-there-a-bug-embedding-srclocs-in-compiled-code-in-bc-8-5-that-was-resolved-in-roughly-8-9/2647 "2024-01-05T18:53:42Z")
Working on some Qi things, we noticed the following error in BC 8.5: Fix marshalling issue · drym-org/qi@c09b926 · GitHub raco setup: error: during making for \/qi-test/tests raco setup: write: cannot marshal val… --- ## [Package removed after trying to update them](https://racket.discourse.group/t/package-removed-after-trying-to-update-them/2521)
**Author:** [@shhyou](https://racket.discourse.group/u/shhyou)\ **Replies:** 4\ **Last updated:** [January 5, 2024, 12:24am UTC](https://racket.discourse.group/t/package-removed-after-trying-to-update-them/2521 "2024-01-05T00:24:27Z")
I installed Racket from git HEAD. When I tried to update some packages, the process failed in the middle so the packages got removed in the end. Has anyone encountered similar problems? I am not sure why gui-easy-lib ap… --- ## [Documenting struct in Scribble](https://racket.discourse.group/t/documenting-struct-in-scribble/2618)
**Author:** [@PLux55](https://racket.discourse.group/u/PLux55)\ **Replies:** 2\ **Last updated:** [January 4, 2024, 10:12pm UTC](https://racket.discourse.group/t/documenting-struct-in-scribble/2618 "2024-01-04T22:12:13Z")
How do you document a field of a struct which has a #:mutable option. There is nothing about this in the documentation. I'm running racket 8.7. --- ## [Redex- fixing incompatible ellipsis match counts for template](https://racket.discourse.group/t/redex-fixing-incompatible-ellipsis-match-counts-for-template/2640)
**Author:** [@oflatt](https://racket.discourse.group/u/oflatt)\ **Replies:** 9\ **Last updated:** [January 4, 2024, 7:24pm UTC](https://racket.discourse.group/t/redex-fixing-incompatible-ellipsis-match-counts-for-template/2640 "2024-01-04T19:24:37Z")
Here's a small redex example that I would like to work: #lang racket (require redex) (define-language L \[numbers (number ...)\] \[pairs ((number number) ...)\]) (define-judgment-form L #:contract (make-pairs num… --- ## [Redex support for sets](https://racket.discourse.group/t/redex-support-for-sets/2644)
**Author:** [@oflatt](https://racket.discourse.group/u/oflatt)\ **Replies:** 2\ **Last updated:** [January 4, 2024, 2:23am UTC](https://racket.discourse.group/t/redex-support-for-sets/2644 "2024-01-04T02:23:22Z")
I have a lot of sets in my semantics, which I've been representing as a list (myset element ...). I define helper metafunctions for sets and typeset them. Is this a good way to do it? I'm thinking of writing a helper l… --- ## [How do you use \`sxpath\` to query sxml that has a default namespace?](https://racket.discourse.group/t/how-do-you-use-sxpath-to-query-sxml-that-has-a-default-namespace/2639)
**Author:** [@e9967a](https://racket.discourse.group/u/e9967a)\ **Replies:** 2\ **Last updated:** [January 3, 2024, 11:16pm UTC](https://racket.discourse.group/t/how-do-you-use-sxpath-to-query-sxml-that-has-a-default-namespace/2639 "2024-01-03T23:16:21Z")
I am trying to use sxpath to query sxml that has a default namespace. For example, the atom feed for the Racket YouTube channel. Unfortunately, the xml has a default namespace (last row). \ **Author:** [@fuxoft](https://racket.discourse.group/u/fuxoft)\ **Replies:** 4\ **Last updated:** [January 2, 2024, 2:05pm UTC](https://racket.discourse.group/t/how-to-remove-the-box-created-by-insert-comment-box-in-drracket/1339 "2024-01-02T14:05:57Z") After creating the comment box using "Insert / Insert comment box" in the REPL window of DrRacket, I cannot find a way to remove it or otherwise continue with my work. Everything I now type appears inside this box and is… [Previous page](https://racket.discourse.group/c/questions/6.md?page=14) [Next page](https://racket.discourse.group/c/questions/6.md?page=16)