# Latest **URL:** https://racket.discourse.group/latest.md?page=48 [Latest](https://racket.discourse.group/latest.md) · [Categories](https://racket.discourse.group/categories.md) · [Tags](https://racket.discourse.group/tags.md) **Page:** 49 --- ## [What have you done with Racket this year?](https://racket.discourse.group/t/what-have-you-done-with-racket-this-year/1584)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 4\ **Last updated:** [February 21, 2023, 4:16am UTC](https://racket.discourse.group/t/what-have-you-done-with-racket-this-year/1584 "2023-02-21T04:16:37Z")
What have you done with Racket this year? :stickman: :racket:​ :racket\_heart: :party\_blob\_gif: :tada: We're proud to be a small part of the amazing things made with Racket in 2022 & looking forward to more in 2023! Te… --- ## [Langjam 17-19th of Feb 2023](https://racket.discourse.group/t/langjam-17-19th-of-feb-2023/1723)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 1\ **Last updated:** [February 17, 2023, 11:33am UTC](https://racket.discourse.group/t/langjam-17-19th-of-feb-2023/1723 "2023-02-17T11:33:12Z")
Hi, ‘JT’ of the @rust-lang / @nushell core team (and previously of the TypeScript core team) is running a ‘Lang Jam’. This is a weekend coding jam where teams or individuals create a programming language based on the th… --- ## [Stream-filter not in constant space?](https://racket.discourse.group/t/stream-filter-not-in-constant-space/1643)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 22\ **Last updated:** [February 17, 2023, 3:05am UTC](https://racket.discourse.group/t/stream-filter-not-in-constant-space/1643 "2023-02-17T03:05:28Z")
The following runs in constant space: (letrec ((make-nats (λ (n) (stream-cons n (make-nats (add1 n))))) (m (λ (x) (zero? (remainder x 10000)))) (stream-filter (λ (f strm) (let ((kar (stream-first str… --- ## [How to use the binding space?](https://racket.discourse.group/t/how-to-use-the-binding-space/1717)
**Author:** [@Antigen-11](https://racket.discourse.group/u/Antigen-11)\ **Replies:** 3\ **Last updated:** [February 17, 2023, 1:18am UTC](https://racket.discourse.group/t/how-to-use-the-binding-space/1717 "2023-02-17T01:18:08Z")
According to the racket reference, A space’s scope is accessed indirectly by using make-interned-syntax-introducer...... The require and provide forms include support for bindings spaces through subforms like for-space … --- ## [\`for-space\` in the \`provide\` form?](https://racket.discourse.group/t/for-space-in-the-provide-form/1715)
**Author:** [@Antigen-11](https://racket.discourse.group/u/Antigen-11)\ **Replies:** 10\ **Last updated:** [February 16, 2023, 11:18pm UTC](https://racket.discourse.group/t/for-space-in-the-provide-form/1715 "2023-02-16T23:18:27Z")
According to the for-space, Like the union of the provide-specs, but adjusted to apply to the binding space specified by space—where space is either an identifier or #f for the default binding space. But I got an err… --- ## [Migrating packages from previous installs in DrRacket](https://racket.discourse.group/t/migrating-packages-from-previous-installs-in-drracket/1719)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 10\ **Last updated:** [February 16, 2023, 6:06pm UTC](https://racket.discourse.group/t/migrating-packages-from-previous-installs-in-drracket/1719 "2023-02-16T18:06:51Z")
Follow-up to my question above about a minimal process for upgrading... I took the opportunity to upgrade to Racket v8.8 (from v8.7). I'm using macOS Monterey 12.6.3. I dragged the Racket v8.8 folder from the .dmg into … --- ## [Making epub files](https://racket.discourse.group/t/making-epub-files/1714)
**Author:** [@hendrikboom3](https://racket.discourse.group/u/hendrikboom3)\ **Replies:** 2\ **Last updated:** [February 15, 2023, 2:44pm UTC](https://racket.discourse.group/t/making-epub-files/1714 "2023-02-15T14:44:49Z")
Does anyone have Racket code that makes epub files? --- ## [Typed Racket: map list items while remembering individual types?](https://racket.discourse.group/t/typed-racket-map-list-items-while-remembering-individual-types/1701)
**Author:** [@cadence](https://racket.discourse.group/u/cadence)\ **Replies:** 3\ **Last updated:** [February 15, 2023, 10:28am UTC](https://racket.discourse.group/t/typed-racket-map-list-items-while-remembering-individual-types/1701 "2023-02-15T10:28:32Z")
First, consider lists where all list items are the same time. I already know that this isn't possible the easy way due to nested polymorphic functions: (map values '(5 6 7)) /!\\ Type Checker: Polymorphic function \`map' … --- ## [Reed-solomon updated](https://racket.discourse.group/t/reed-solomon-updated/1702)
**Author:** [@simmone](https://racket.discourse.group/u/simmone)\ **Replies:** 2\ **Last updated:** [February 15, 2023, 1:25am UTC](https://racket.discourse.group/t/reed-solomon-updated/1702 "2023-02-15T01:25:32Z")
The reed-solomon library is updated, bug fix and simplify code. Reed Solomon(rs) is a error recover algorithm, use rs to encode a piece of data, generate 2t's length's extra data to append to the original data. So can r… --- ## [Hash-table name?](https://racket.discourse.group/t/hash-table-name/1699)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 2\ **Last updated:** [February 13, 2023, 9:20pm UTC](https://racket.discourse.group/t/hash-table-name/1699 "2023-02-13T21:20:56Z")
I’ve been following the topic RFC: hash table pattern matching. The Racket Reference (4.15 Hash Tables) mentions performance differences between mutable and immutable versions. In other languages Hash tables go by othe… --- ## [Macro in Racket language?](https://racket.discourse.group/t/macro-in-racket-language/1709)
**Author:** [@Antigen-11](https://racket.discourse.group/u/Antigen-11)\ **Replies:** 7\ **Last updated:** [February 13, 2023, 3:09pm UTC](https://racket.discourse.group/t/macro-in-racket-language/1709 "2023-02-13T15:09:37Z")
\> (version) "8.8" \> (require (for-syntax racket/base)) \> (define-syntax-rule (make-module n (l ...) i b) (module n racket/base (require l ...) (provide i) (define i b))) \> (make-module t () x 1) str… --- ## [Expressing contract conditions related to underlying data structures](https://racket.discourse.group/t/expressing-contract-conditions-related-to-underlying-data-structures/1707)
**Author:** [@Balrrach](https://racket.discourse.group/u/Balrrach)\ **Replies:** 0\ **Last updated:** [February 12, 2023, 5:41pm UTC](https://racket.discourse.group/t/expressing-contract-conditions-related-to-underlying-data-structures/1707 "2023-02-12T17:41:55Z")
Hello. I'm new to DbC and I'm trying to understand some of its fundamental concepts and how they could be applied to racket specifically. My questions is this: Suppose I want to define an interface. In order for the inte… --- ## [Unexpected behaviour of quasiquote when binding unquote and unquote-splicing](https://racket.discourse.group/t/unexpected-behaviour-of-quasiquote-when-binding-unquote-and-unquote-splicing/1700)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 2\ **Last updated:** [February 12, 2023, 10:56am UTC](https://racket.discourse.group/t/unexpected-behaviour-of-quasiquote-when-binding-unquote-and-unquote-splicing/1700 "2023-02-12T10:56:13Z")
\#lang racket/base (let ((unquote-splicing 4) (unquote add1)) \`(a b unquote ,(map unquote '(0 1 2 3)) ,(unquote unquote-splicing))) --\> (a b unquote ,(map . ,'(0 1 2 3)) ,,unquote-splicing) but should it not produ… --- ## [Scheme+ v5.0 for Racket](https://racket.discourse.group/t/scheme-v5-0-for-racket/1704)
**Author:** [@damien\_mattei](https://racket.discourse.group/u/damien_mattei)\ **Replies:** 0\ **Last updated:** [February 12, 2023, 9:31am UTC](https://racket.discourse.group/t/scheme-v5-0-for-racket/1704 "2023-02-12T09:31:46Z")
Hello, i just released a new version of Scheme+ Scheme+ is an extension of the syntax of the Scheme language. Scheme+ makes it easy the assignment of Scheme objects in infix (works also in prefix) notation with a few n… --- ## [Convex Hull with Metapict](https://racket.discourse.group/t/convex-hull-with-metapict/1694)
**Author:** [@soegaard](https://racket.discourse.group/u/soegaard)\ **Replies:** 0\ **Last updated:** [February 8, 2023, 10:15am UTC](https://racket.discourse.group/t/convex-hull-with-metapict/1694 "2023-02-08T10:15:20Z")
The latest blog post is on convex hulls: https://soegaard.github.io/blog/metapict/#7 --- ## [Resources for continuations / delimited continuations / racket continuation functionality from a beginner perspective?](https://racket.discourse.group/t/resources-for-continuations-delimited-continuations-racket-continuation-functionality-from-a-beginner-perspective/1690)
**Author:** [@dr-neptune](https://racket.discourse.group/u/dr-neptune)\ **Replies:** 3\ **Last updated:** [February 7, 2023, 11:55pm UTC](https://racket.discourse.group/t/resources-for-continuations-delimited-continuations-racket-continuation-functionality-from-a-beginner-perspective/1690 "2023-02-07T23:55:45Z")
Hi folks, beginner here on the path of learning continuations. I'm seeking resources for learning more about them. They seem very general, so anything would be appreciated -- however I would like them to be from the per… --- ## [Tab font in a tab-panel% doesn't want to change](https://racket.discourse.group/t/tab-font-in-a-tab-panel-doesnt-want-to-change/1692)
**Author:** [@lannydpittman](https://racket.discourse.group/u/lannydpittman)\ **Replies:** 1\ **Last updated:** [February 7, 2023, 10:38pm UTC](https://racket.discourse.group/t/tab-font-in-a-tab-panel-doesnt-want-to-change/1692 "2023-02-07T22:38:50Z")
Here is the situation: I am trying to make an application in Racket that will be used with a touchscreen. Naturally, I wanted to make lists, multi-selects, tabs, etc. a larger size, so that they can be more easily see… --- ## [Helpful: suggests a closest name on unbound identifier error](https://racket.discourse.group/t/helpful-suggests-a-closest-name-on-unbound-identifier-error/626)
**Author:** [@sorawee](https://racket.discourse.group/u/sorawee)\ **Replies:** 14\ **Last updated:** [February 7, 2023, 4:36pm UTC](https://racket.discourse.group/t/helpful-suggests-a-closest-name-on-unbound-identifier-error/626 "2023-02-07T16:36:25Z")
Some tools in other programming languages can suggest a closest name when an unbound identifier error occurs. (image taken from can't tokenize a string and pass it to struct in c++ - Stack Overflow) I attempted to i… --- ## [Check-syntax arrow with rename-in](https://racket.discourse.group/t/check-syntax-arrow-with-rename-in/1644)
**Author:** [@greghendershott](https://racket.discourse.group/u/greghendershott)\ **Replies:** 34\ **Last updated:** [February 6, 2023, 4:22pm UTC](https://racket.discourse.group/t/check-syntax-arrow-with-rename-in/1644 "2023-02-06T16:22:55Z")
Hovering on get-pure-port, two arrows are drawn to it: From importing net/url. From the rename-in of get-pure-port to a different name --- in an unrelated submodule m that isn't even in scope for the main, file mod… --- ## [Custom scribble site design](https://racket.discourse.group/t/custom-scribble-site-design/1674)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 1\ **Last updated:** [February 6, 2023, 8:31am UTC](https://racket.discourse.group/t/custom-scribble-site-design/1674 "2023-02-06T08:31:22Z")
Hi I’d like to make a variant of #lang scribble/manual that has keeps the same site structure; table of contents page with individual chapter pages, but has a preamble followers by the table of contents as tiled images … --- ## [Racket meet-up Saturday 4 Feb at 18:00 UTC :racket:](https://racket.discourse.group/t/racket-meet-up-saturday-4-feb-at-18-00-utc/1684)
**Author:** [@spdegabrielle](https://racket.discourse.group/u/spdegabrielle)\ **Replies:** 2\ **Last updated:** [February 4, 2023, 8:01pm UTC](https://racket.discourse.group/t/racket-meet-up-saturday-4-feb-at-18-00-utc/1684 "2023-02-04T20:01:01Z")
Racket meet-up Saturday 4 Feb at 18:00 UTC :racket: At this meet-up: Racketfest! Show and tell News & rumours AOB Meet-up time at your location: 2023-02-04T18:00:00Z (UTC) (Discourse should convert this for you) In … --- ## [Call for participation: Racketfest 2023](https://racket.discourse.group/t/call-for-participation-racketfest-2023/1683)
**Author:** [@jesse](https://racket.discourse.group/u/jesse)\ **Replies:** 2\ **Last updated:** [February 4, 2023, 11:20am UTC](https://racket.discourse.group/t/call-for-participation-racketfest-2023/1683 "2023-02-04T11:20:38Z")
The Racketfest 2023 program is all set! Nine speakers will be joining us to share all sorts of Racket wisdom, coming from all corners of the Racket ecosystem: academia and industry, hobbyist and professional; application… --- ## [Release Announcement for v8.8](https://racket.discourse.group/t/release-announcement-for-v8-8/1685)
**Author:** [@jbclements](https://racket.discourse.group/u/jbclements)\ **Replies:** 4\ **Last updated:** [February 4, 2023, 6:34am UTC](https://racket.discourse.group/t/release-announcement-for-v8-8/1685 "2023-02-04T06:34:26Z")
The release announcement sketch that I have so far is below. Please respond with new items and/or edits. Please phrase announcements using complete sentences and avoid the word "now". ---------------------------------… --- ## [(define-type … (Instance X)) breaks when X is a parametric type synonym, since Racket 8.7](https://racket.discourse.group/t/define-type-instance-x-breaks-when-x-is-a-parametric-type-synonym-since-racket-8-7/1682)
**Author:** [@scolobb](https://racket.discourse.group/u/scolobb)\ **Replies:** 1\ **Last updated:** [February 3, 2023, 4:46pm UTC](https://racket.discourse.group/t/define-type-instance-x-breaks-when-x-is-a-parametric-type-synonym-since-racket-8-7/1682 "2023-02-03T16:46:06Z")
Hi, Suppose I have the following typed class: (define my-class% (class object% #:forall (A) (super-new) (init-field \[x : A\]) (define/public (get-x) x))) I can define a synonym for the type of this cl… --- ## [DrRacket help function not working on MacOS Monterey](https://racket.discourse.group/t/drracket-help-function-not-working-on-macos-monterey/1677)
**Author:** [@TroutStalker](https://racket.discourse.group/u/TroutStalker)\ **Replies:** 2\ **Last updated:** [January 31, 2023, 8:33pm UTC](https://racket.discourse.group/t/drracket-help-function-not-working-on-macos-monterey/1677 "2023-01-31T20:33:17Z")
I'm new to Racket. On macOS Monterey, I installed Racket, DrRacket etc. by downloading the dmg file and installing it into /Applications. It seems to work but I can't get the help function to work. I put the cursor on a … --- ## [Do I really need a custodian?](https://racket.discourse.group/t/do-i-really-need-a-custodian/1680)
**Author:** [@joskoot](https://racket.discourse.group/u/joskoot)\ **Replies:** 0\ **Last updated:** [January 31, 2023, 8:03pm UTC](https://racket.discourse.group/t/do-i-really-need-a-custodian/1680 "2023-01-31T20:03:35Z")
\#| I have my toy evaluator. I do not allow my evaluator to change parameters. Therefore I run the evaluator proper in a thread. I tried call-with-parameterization, but to no avail. I want ports opened by expressions pa… --- ## [Call for Participation: BOB 2023 (Berlin, March 17)](https://racket.discourse.group/t/call-for-participation-bob-2023-berlin-march-17/1554)
**Author:** [@mike](https://racket.discourse.group/u/mike)\ **Replies:** 1\ **Last updated:** [January 31, 2023, 12:14pm UTC](https://racket.discourse.group/t/call-for-participation-bob-2023-berlin-march-17/1554 "2023-01-31T12:14:27Z")
========================================================================= BOB 2023 Conference “What happens if we simply use what’s best?” March 17, 2023, Berlin https://bobkonf.de/2023/ Pr… --- ## [Web server subprocess logging to stdout sometimes not available until after subprocess terminates](https://racket.discourse.group/t/web-server-subprocess-logging-to-stdout-sometimes-not-available-until-after-subprocess-terminates/1673)
**Author:** [@joeld](https://racket.discourse.group/u/joeld)\ **Replies:** 12\ **Last updated:** [January 30, 2023, 7:41pm UTC](https://racket.discourse.group/t/web-server-subprocess-logging-to-stdout-sometimes-not-available-until-after-subprocess-terminates/1673 "2023-01-30T19:41:35Z")
I’m running raco static-web from inside another Racket program using subprocess\[1\], and, inside a thread, monitoring the subprocess’s stdout with sync/enable-break. The weird thing is that with raco static-web in particu… --- ## [What exactly is #lang](https://racket.discourse.group/t/what-exactly-is-lang/1675)
**Author:** [@Panadestein](https://racket.discourse.group/u/Panadestein)\ **Replies:** 4\ **Last updated:** [January 30, 2023, 2:38pm UTC](https://racket.discourse.group/t/what-exactly-is-lang/1675 "2023-01-30T14:38:18Z")
Hi, very basic question here. What is the correct name of "#lang" in Racket ? Is it a "reader form", a "directive", a "reader macro", or something else? --- ## [Some vim-related things](https://racket.discourse.group/t/some-vim-related-things/529)
**Author:** [@benknoble](https://racket.discourse.group/u/benknoble)\ **Replies:** 18\ **Last updated:** [January 30, 2023, 2:30pm UTC](https://racket.discourse.group/t/some-vim-related-things/529 "2023-01-30T14:30:50Z")
Here are some things I have made, modified, or contributed to that make using Vim to edit Racket nicer: General ALE support (including the racket-langserver LSP: racket: support racket-langserver lsp by benknoble · Pul… [Previous page](https://racket.discourse.group/latest.md?page=47) [Next page](https://racket.discourse.group/latest.md?page=49)