Re: [racket-users] DrRackGit & LibGit2
I should be clear, I ran the libgit2 tests by hard coding the location of the library and running them manually. I don’t really know what I’m doing so that was the best I could muddle through. S. On Thu, 7 Dec 2017 at 22:28, Stephen De Gabrielle wrote: > Only on macOS, but most tests passed. > S. > On Thu, 7 Dec 2017 at 22:15, John Clements > wrote: > >> Bradley was a student of mine, so I’m interested generally. Have you >> checked to see whether adding the libgit2 dependency allows the tests to >> pass? >> >> John >> >> > On Dec 7, 2017, at 10:27 AM, Stephen De Gabrielle < >> spdegabrie...@gmail.com> wrote: >> > >> > >> > Hi, >> > https://pkgs.racket-lang.org/package/Drrackgit >> > https://github.com/bbusching/drrackgit >> > https://pkgs.racket-lang.org/package/libgit2 >> > https://github.com/bbusching/libgit2 >> > https://libgit2.github.com/ >> > >> > I was very excited when I found the DrRackGit tool in the Racket >> packages, but saddened to find it is currently failing. >> > >> > Bradley, the original developer was kind enough to diagnose the issue ( >> it is missing the dependency on the libgit2 library.) and add a compatible >> licence, but isn’t able to maintain it at the moment. >> > >> > Is anyone interested in fixing the libgit2 package? >> > >> > Kind regards, >> > >> > Stephen >> > >> > PS I have built the lib2git library on macOS, but I lack the required >> experience in FFI and I can’t currently build for Linux or windows. >> > >> > >> > >> > >> > >> > >> > -- >> > Kind regards, >> > Stephen >> > -- >> > Ealing (London), UK >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups "Racket Users" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> an email to racket-users+unsubscr...@googlegroups.com. >> > For more options, visit https://groups.google.com/d/optout. >> >> >> >> -- > Kind regards, > Stephen > -- > Ealing (London), UK > -- Kind regards, Stephen -- Ealing (London), UK -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] DrRackGit & LibGit2
> On Dec 7, 2017, at 2:34 PM, Stephen De Gabrielle > wrote: > > I should be clear, I ran the libgit2 tests by hard coding the location of the > library and running them manually. I don’t really know what I’m doing so that > was the best I could muddle through. That doesn’t sound ideal. Probably it’s better to deliver the library with the package on macos & windows, & ask user to install using package manager on linux. Sounds like entertaining work, and I’ve been meaning to take a look at this for quite a while now, but I definitely don’t have any time before next Tuesday. John > S. > > On Thu, 7 Dec 2017 at 22:28, Stephen De Gabrielle > wrote: > Only on macOS, but most tests passed. > S. > On Thu, 7 Dec 2017 at 22:15, John Clements wrote: > Bradley was a student of mine, so I’m interested generally. Have you checked > to see whether adding the libgit2 dependency allows the tests to pass? > > John > > > On Dec 7, 2017, at 10:27 AM, Stephen De Gabrielle > > wrote: > > > > > > Hi, > > https://pkgs.racket-lang.org/package/Drrackgit > > https://github.com/bbusching/drrackgit > > https://pkgs.racket-lang.org/package/libgit2 > > https://github.com/bbusching/libgit2 > > https://libgit2.github.com/ > > > > I was very excited when I found the DrRackGit tool in the Racket packages, > > but saddened to find it is currently failing. > > > > Bradley, the original developer was kind enough to diagnose the issue ( it > > is missing the dependency on the libgit2 library.) and add a compatible > > licence, but isn’t able to maintain it at the moment. > > > > Is anyone interested in fixing the libgit2 package? > > > > Kind regards, > > > > Stephen > > > > PS I have built the lib2git library on macOS, but I lack the required > > experience in FFI and I can’t currently build for Linux or windows. > > > > > > > > > > > > > > -- > > Kind regards, > > Stephen > > -- > > Ealing (London), UK > > > > -- > > You received this message because you are subscribed to the Google Groups > > "Racket Users" group. > > To unsubscribe from this group and stop receiving emails from it, send an > > email to racket-users+unsubscr...@googlegroups.com. > > For more options, visit https://groups.google.com/d/optout. > > > > -- > Kind regards, > Stephen > -- > Ealing (London), UK > -- > Kind regards, > Stephen > -- > Ealing (London), UK -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] DrRackGit & LibGit2
HI John, Thanks for taking the time to look at this - anytime you have is appreciated. As I'm not familiar with FFI and I'm not clear what the benefits over git that lib2git brings on Windows/Linux/Macos I was honestly considering leaving 'as-is' libgit2 and adding using git as an option in DrRackGit (via racket/system) on the grounds that users will have git installed anyway. (I'm pretty sure 'Github desktop' uses git, though it might have changed to libgit2 in an update) If you feel FFI/Libgit2 is worth the effort I'll follow you lead - please don't hesitate to give me any task that will help. > I definitely don’t have any time before next Tuesday. Not a problem - I'm enthusiastic but DrRacket isn't my day job either. 😁 Thanks again, Stephen --- Welcome to DrRacket, version 6.11 [3m]. Language: racket, with debugging; memory limit: 128 MB. # 1 repository > libgit2 > git repo path . FAILURE name: check-equal? location: test-libgit2.rkt:100:16 actual: # expected: # config > libgit2 > open level . ERROR git_config_open_level: contract violation expected: 0 received: "7: no config file exists for the given level '1'" 45 success(es) 1 failure(s) 1 error(s) 47 test(s) run 2 > On Thu, Dec 7, 2017 at 10:57 PM, John Clements wrote: > > > > On Dec 7, 2017, at 2:34 PM, Stephen De Gabrielle < > spdegabrie...@gmail.com> wrote: > > > > I should be clear, I ran the libgit2 tests by hard coding the location > of the library and running them manually. I don’t really know what I’m > doing so that was the best I could muddle through. > > That doesn’t sound ideal. Probably it’s better to deliver the library with > the package on macos & windows, & ask user to install using package manager > on linux. Sounds like entertaining work, and I’ve been meaning to take a > look at this for quite a while now, but I definitely don’t have any time > before next Tuesday. > > John > > > S. > > > > On Thu, 7 Dec 2017 at 22:28, Stephen De Gabrielle < > spdegabrie...@gmail.com> wrote: > > Only on macOS, but most tests passed. > > S. > > On Thu, 7 Dec 2017 at 22:15, John Clements > wrote: > > Bradley was a student of mine, so I’m interested generally. Have you > checked to see whether adding the libgit2 dependency allows the tests to > pass? > > > > John > > > > > On Dec 7, 2017, at 10:27 AM, Stephen De Gabrielle < > spdegabrie...@gmail.com> wrote: > > > > > > > > > Hi, > > > https://pkgs.racket-lang.org/package/Drrackgit > > > https://github.com/bbusching/drrackgit > > > https://pkgs.racket-lang.org/package/libgit2 > > > https://github.com/bbusching/libgit2 > > > https://libgit2.github.com/ > > > > > > I was very excited when I found the DrRackGit tool in the Racket > packages, but saddened to find it is currently failing. > > > > > > Bradley, the original developer was kind enough to diagnose the issue > ( it is missing the dependency on the libgit2 library.) and add a > compatible licence, but isn’t able to maintain it at the moment. > > > > > > Is anyone interested in fixing the libgit2 package? > > > > > > Kind regards, > > > > > > Stephen > > > > > > PS I have built the lib2git library on macOS, but I lack the required > experience in FFI and I can’t currently build for Linux or windows. > > > > > > > > > > > > > > > > > > > > > -- > > > Kind regards, > > > Stephen > > > -- > > > Ealing (London), UK > > > > > > -- > > > You received this message because you are subscribed to the Google > Groups "Racket Users" group. > > > To unsubscribe from this group and stop receiving emails from it, send > an email to racket-users+unsubscr...@googlegroups.com. > > > For more options, visit https://groups.google.com/d/optout. > > > > > > > > -- > > Kind regards, > > Stephen > > -- > > Ealing (London), UK > > -- > > Kind regards, > > Stephen > > -- > > Ealing (London), UK > > > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] scheme-script executable?
This morning I stumbled across Appendix D to R6RS ( http://www.r6rs.org/final/html/r6rs-app/r6rs-app-Z-H-6.html), which suggests that implementations provide an executable named scheme-script for the purpose of executing portable scripts. It seems that Racket does not currently provide such an executable. Should it? (Of course I understand that Racket is not a Scheme implementation, but it does contain an R6RS implementation.) The rationale given in the report seems persuasive to me, having at least a little bit of experience wrangling Unix-style scripts that try to be somewhat portable. It seems like just making scheme-script an alias for the racket executable would be sufficient. -Philip -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: stumped
Thanks Alex, Much appreciated! Stephen On Thu, 14 Dec 2017 at 04:50, Alex Harsanyi wrote: > I built a similar control, although it does not represent directory paths, > just labels which are stacked vertically. I ended up defining a structure > to hold the text and width + height of each label and keep these structures > in a list. In my case, all labels have the same size so converting a mouse > coordinate to a list index is just arithmetic, but it could be extended to > support variable width labels and just search the list in linear time to > convert a mouse coordinate to a list index. The number of items in the > control should be small enough that linear search should not be a > disadvantage. > > You can find the definition of the control here: > > https://github.com/alex-hhh/ActivityLog2/blob/master/rkt/widgets.rkt#L1910 > > To convert it to variable width labels, the `hover-candiate` function > would have to be changed (third `cond` option) to do a linear search on the > label widths. `label-box-dimensions` would also have to change to report > the actual label width and height for all labels (currently all labels have > the dimensions of the largest one). > > Best Regards, > Alex. > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- Kind regards, Stephen -- Ealing (London), UK -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Y combinator
> On Jan 13, 2018, at 11:53 AM, Hendrik Boom wrote: > > On Sat, Jan 13, 2018 at 08:14:30AM -0800, Zelphir Kaltstahl wrote: >> >> Anyway, I hope to understand how the Y-combinator works with the help of >> "The Little Schemer", which I am reading currently. I am not at that >> chapter yet. I am taking my time, first thinking through the stuff and >> later typing it into the machine and thinking about it again, sometimes >> noticing some detail when I type the code and sometimes making a little >> experiment with that code. Already on my way through "The Little Schemer" I >> hit some useful procedures, which helped me with a totally unrelated >> problem when coding my blog in Racket. So it's definitely useful. > > The Y combinator comes from the original lambda calculus, which was a > formal system for computational logic and it elicidated how bound and > free variables work. > > But the system had no built-in mechanism for defining a recursive > function. > > Instead, the Y-combinator was invented -- a lamnda expression that > enable you to make a recursive function essentially by passing the > functiion as an argument to itself. Receiving itself as a parameter, it > was capable of calling its parameter, which was itself. > > Have fun deciphering the code. It took me while, too, way back in the > 60's. TLL/TLS does not dump the code on the reader. It develops it, step by step, w/o any mystery. It is still a serious “reading” exercise for most readers and a rather satisfying one I am told. — Matthias -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Y combinator
I find this <https://web.archive.org/web/20170813054608/http://mvanier.livejournal.com/2897.html> (now dead, but archived) blog post on Y both well paced and approachable. http://mvanier.livejournal.com/2897.html <https://web.archive.org/web/20170813054608/http://mvanier.livejournal.com/2897.html> The post's author considers it to be a massively expanded version of Ch 9 from *TLT/TLS.* I have also suggested Yin Wang's slides on Reinventing the Y-Combinator <https://www.slideshare.net/yinwang0/reinventing-the-ycombinator>, which you might find you enjoy. Best, JBH On Sat, Jan 13, 2018 at 11:57 AM, Matthias Felleisen wrote: > > > On Jan 13, 2018, at 11:53 AM, Hendrik Boom > wrote: > > > > On Sat, Jan 13, 2018 at 08:14:30AM -0800, Zelphir Kaltstahl wrote: > >> > >> Anyway, I hope to understand how the Y-combinator works with the help of > >> "The Little Schemer", which I am reading currently. I am not at that > >> chapter yet. I am taking my time, first thinking through the stuff and > >> later typing it into the machine and thinking about it again, sometimes > >> noticing some detail when I type the code and sometimes making a little > >> experiment with that code. Already on my way through "The Little > Schemer" I > >> hit some useful procedures, which helped me with a totally unrelated > >> problem when coding my blog in Racket. So it's definitely useful. > > > > The Y combinator comes from the original lambda calculus, which was a > > formal system for computational logic and it elicidated how bound and > > free variables work. > > > > But the system had no built-in mechanism for defining a recursive > > function. > > > > Instead, the Y-combinator was invented -- a lamnda expression that > > enable you to make a recursive function essentially by passing the > > functiion as an argument to itself. Receiving itself as a parameter, it > > was capable of calling its parameter, which was itself. > > > > Have fun deciphering the code. It took me while, too, way back in the > > 60's. > > > TLL/TLS does not dump the code on the reader. It develops it, > step by step, w/o any mystery. It is still a serious “reading” exercise > for most readers and a rather satisfying one I am told. — Matthias > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- JBH -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Understanding prop:impersonator-of
I'm trying to understand the use of the prop:impersonator-of struct property, but the following program doesn't work the way I would have expected: #lang racket (struct our-impersonate-proc (f orig) #:property prop:impersonator-of (lambda (x) (displayln 'hi) (our-impersonate-proc-orig x)) #:property prop:procedure (struct-field-index f)) (impersonator-of? (our-impersonate-proc add1 values) values) The call to impersonator-of? doesn't seem to go through our prop:impersonator-of at all because we don't 'hi displayed when the program is run. Am I misunderstanding the way to use prop:impersonator-of ? I don't fully understand the documentation, so it's possible this isn't something that prop:impersonator-of is intended for. Thanks Dan -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Apparent Datalog error?
Walking through the datalog tutorial I got the following transcript: Welcome to DrRacket, version 6.12 [3m]. Language: datalog, with debugging; memory limit: 512 MB. > parent(john, douglas). > parent(john, douglas)? parent(john, douglas). > parent(john, evlyn)? > parent(bob, john). > parent(A, B)? parent(john, douglas). parent(bob, john). > parent(ebbon, bob). > parent(john, B)? parent(john, douglas). > parent(A, A)? > ancestor(A, B) :- parent(A, B). > ancestor(A, B) :- parent(A, C), parent(C, B). > ancestor(A, B)? ancestor(ebbon, bob). ancestor(bob, john). ancestor(john, douglas). ancestor(bob, douglas). ancestor(ebbon, john). > It seems that the correct answer should also include ancestor(ebbon, douglas). Am I doing something wrong? -Kevin -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Datalog Question
Something like kevin(Y) :- foo(x, Y), Y != 3. kevin(Y)? On Wed, Jan 31, 2018 at 5:13 PM, Kevin Forchione wrote: > Can anyone tell me how I would use the datalog = and != tokens? The > documentation says they can separate terms, such as != . In the > program below, how would I create a query for foo(x, ?) where ? is not 3? > > #lang datalog > > foo(bil, 1). > foo(bob, 3). > foo(joe, 2). > > I imagine I’d have to create a rule of some sort. > > -Kevin > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- -=[ Jay McCarthy http://jeapostrophe.github.io]=- -=[ Associate ProfessorPLT @ CS @ UMass Lowell ]=- -=[ Moses 1:33: And worlds without number have I created; ]=- -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] raco distribute help
Hi everyone, I'm having a hard time understanding the docs for raco exe and raco distribute. tl;dr main.rkt has to (dynamic-require user-selected.rkt) and user-selected.rkt is written in a different #lang and requires a file from this program. How do I glue these pieces together for raco exe / raco distribute? My program has two things which seem to be hanging me up. The first is that a file is grabbed with (dynamic-require) based on a path obtained by the user with (get-file ...). This file is written in a different #lang and uses (require ...) for some syntax transformers. The exe builds alright but chokes when used because it can't find the #lang and can't find the (require ...). Ideally the file which is given to (dynamic-require ...) could be in any folder the user chooses, but then the (require ...) statement would be all over the map and I don't understand what I'm supposed to do to resolve this. If it helps, the file is already required by the program and isn't used only by the user-selected file. ++copy-collects doesn't seem to grab #lang folders correctly or I don't understand how to use it. Can someone give me some guidance here? Thanks, Deren -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Quick regexp question
Sorry if I've missed this in the documentation, but I don't see it, and it is starting to bother me. In Powershell. Python, and Splunk I'm able to perform automatic field extraction on strings and access the values of fields by name. Is there a way to do this in Racket? Of course, pairing matches with field names by index is an option, but not as convenient in some situations. Take string "2018-02-02T11:26:34 someuser some-computername01 233.194.20.110 something broke" as a trivial example. Powershell: "2018-02-02T11:26:34 someuser some-computername01 233.194.20.110 something broke" -match "^(?[\d\-T:]+)\s(?\w+)\s(?[\w\-\d]+)\s(?[\d\.]+)\s(?.+)$" | Out-Null $matches.date $matches.username $matches.hostname $matches.IP $matches.message Python: m = re.match( "^(?P[\d\-T:]+)\s(?P\w+)\s(?P[\w\-\d]+)\s(?P[\d\.]+)\s(?P.+)$" , "2018-02-02T11:26:34 someuser some-computername01 233.194.20.110 something broke") m['Date'] m['Username'] m['Hostname'] m['IP'] m['Message'] Both output: 2018-02-02T11:26:34 someuser some-computername01 233.194.20.110 something broke -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] [CFP] ICOOOLPS 2018
Call for Papers: ICOOOLPS'18 13th Workshop on Implementation, Compilation, Optimization of Object- Oriented Languages, Programs and Systems Co-located with ECOOP 2018 held Mon 16 - Sun 22 July in Amsterdam, Netherlands Twitter: @ICOOOLPS URL: https://conf.researchr.org/track/ecoop-issta-2018/ICOOOLPS-2018-papers The ICOOOLPS workshop series brings together researchers and practitioners working in the field of language implementation and optimization. The goal of the workshop is to discuss emerging problems and research directions as well as new solutions to classic performance challenges. The topics of interest for the workshop include techniques for the implementation and optimization of a wide range of languages including but not limited to object-oriented ones. Furthermore, meta-compilation techniques or language-agnostic approaches are welcome, too. ### Topics of Interest A non-exclusive list of topics of interest for this workshop is: - Implementation and optimization of fundamental languages features (from automatic memory management to zero-overhead metaprogramming) - Runtime systems technology (libraries, virtual machines) - Static, adaptive, and speculative optimizations and compiler techniques - Meta-compilation techniques and language-agnostic approaches for the efficient implementation of languages - Compilers (intermediate representations, offline and online optimizations,…) - Empirical studies on language usage, benchmark design, and benchmarking methodology - Resource-sensitive systems (real-time, low power, mobile, cloud) - Studies on design choices and tradeoffs (dynamic vs. static compilation, heuristics vs. programmer input,…) - Tooling support, debuggability and observability of languages as well as their implementations ### Workshop Format and Submissions This workshop welcomes the presentation and discussion of new ideas and emerging problems that give a chance for interaction and exchange. More mature work is welcome as part of a mini-conference format, too. We aim to interleave interactive brainstorming and demonstration sessions between the formal presentations to foster an active exchange of ideas. The workshop papers will be published in ACM DL or an open archive (to be confirmed). Papers are to be submitted using the sigplanconf LaTeX template (http://www.sigplan.org/Resources/LaTeXClassFile/). Please submit contributions via EasyChair: https://easychair.org/conferences/submission_show_all.cgi?a=17114062 ### Important Dates Submissions: 18 May 2018 Author Notification: 8 June 2018 ### Program Committee The program committee consists of the organizers and the following reviewers: Nada Amin, University of Cambridge Clément Béra, RMOD - INRIA Lille Nord Europe Shigeru Chiba, University of Tokyo Benoit Daloze, JKU Linz Görel Hedin, Lund University Eric Jul, University of Oslo Stefan Marr, University of Kent Eliot Miranda, Cadence Design Systems Sarah Mount, King's College London Tobias Pape, Hasso Plattner Institute Jennifer Sartor, Vrije Universiteit Brussel + University Ghent ### Workshop Organizers Tim Felgentreff, Oracle Labs Potsdam Olivier Zendra, INRIA / LORIA -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
I use Nix, but mostly for Haskell currently, rather than Racket. I did prototype a nix project with Racket. I don't have the sources at my fingertips. I'll report if I look back and see anything helpful for you. It looks like you are trying to tie into the Racket package system. We didn't try to do so, we were just trying to go from a git clone to a common development environment in one step. I do remember modifying the racket derivation in the nixpkgs repo. I don't think that got pushed upstream. The Racket derivation needed to be parameterized to find the opengl libs/drivers. I also remember that I couldn't get this to work reliably on any OS except NixOS. Any opengl program was going to have similar trouble since the libs are a function of the drivers which can't really be provided by Nix on non NixOS platforms. This situation was more of a reflection on the state of OpenGL than Nix in my opinion, but we ended up developing in a NixOs vm for this reason only. I don't remember what other changes I made, this was the biggest pain point. I did integrate with other foreign functions. -- Anthony Carrico -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
At Wed, 14 Feb 2018 03:44:44 -0800 (PST), Claes Wallin wrote: > 1. The package I'm currently building probably needs to be the installation > path for racket, so that I can use installation scope and have links.rktd > and other things end up in the expected places. That sounds right. > 2. As my dependencies and their dependencies have already been installed > once, and I want to use them from their already-prepared destination, it > should be possible to just merge together the links.rktd of my dependencies > and add my own package to the list, and that should be my new links.rktd. > > [...] > > I've finally found that the way to customize where racket finds things is > to mess about with `racket -G` and the config.rktd file. I was hoping that > I could just add the share/racket directories of my dependencies to > 'links-search-files, but it doesn't seem that simple. I think this is also the right idea, but I think you need to set 'pkg-search-dirs in parallel to 'links-search-files within "config.rktd". The two separate entries reflect how the package system is built on top of the collection-link layer, but it has to keep additional information that is specific to the package layer. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
On Thursday, February 15, 2018 at 3:16:24 AM UTC+8, Matthew Flatt wrote: > > At Wed, 14 Feb 2018 03:44:44 -0800 (PST), Claes Wallin wrote: > > > I've finally found that the way to customize where racket finds things > is > > to mess about with `racket -G` and the config.rktd file. I was hoping > that > > I could just add the share/racket directories of my dependencies to > > 'links-search-files, but it doesn't seem that simple. > > I think this is also the right idea, but I think you need to set > 'pkg-search-dirs in parallel to 'links-search-files within > "config.rktd". > > The two separate entries reflect how the package system is built on top > of the collection-link layer, but it has to keep additional information > that is specific to the package layer. > Thanks! I'll try that. I thought packages were always looked up through the collections, but maybe that's a difference between package dependencies when installing and the way you look them up when you refer to them in the code? -- /c -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
On Thursday, February 15, 2018 at 3:01:08 AM UTC+8, Anthony Carrico wrote: > > The Racket derivation needed to be > parameterized to find the opengl libs/drivers. I also remember that I > couldn't get this to work reliably on any OS except NixOS. Any opengl > program was going to have similar trouble since the libs are a function > of the drivers which can't really be provided by Nix on non NixOS > platforms. Wow, ok. > This situation was more of a reflection on the state of > OpenGL than Nix in my opinion, but we ended up developing in a NixOs vm > for this reason only. > Yeah, that sounds like an oddity. One nice thing you can do once you have racket2nix is that you can have your racket package generated as a nix package, and then override the nix package to have native dependencies, which I hope will be very helpful to people in your situation in the future. -- /c -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
On Thursday, February 15, 2018 at 9:18:14 AM UTC+8, Claes Wallin wrote: > > On Thursday, February 15, 2018 at 3:16:24 AM UTC+8, Matthew Flatt wrote: >> >> > I think this is also the right idea, but I think you need to set >> 'pkg-search-dirs in parallel to 'links-search-files within >> "config.rktd". >> > > Thanks! I'll try that. It worked! So now it even complains when I try to install base against a full racket, that base already exists. This is a good thing. :-) But when I'm installing against minimal I get: /nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/bin/racket -G /nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/etc/racket -U -X /nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/collects -S /nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/share/racket/collects (current-library-collection-links): (#f /nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/share/racket) (find-library-collection-links): (#f /nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/share/racket) (find-links-file): /nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/links.rktd (current-library-collection-paths): (/nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/collects /nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/share/racket/collects) (find-library-collection-paths): (/nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/collects) (find-pkgs-dir): /nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/pkgs (get-pkgs-search-dirs): (/nix/store/rm4jgl2jhdmv0b2jlr2jmziih8clximf-racket-minimal-6.12/share/racket/pkgs) collection-file-path: collection not found collection: "setup" in collection directories: /nix/store/gfwrnnq5ql1b35i03cs3xyzrflcrapfi-base/share/racket/collects So (current-library-collection-paths) reports both base/.../collects and racket-minimal-6.12/.../collects. And my little dump script, which printed that value, successfully requires setup/dirs, so I wonder why raco (or something) can't. -- /c -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
Re opengl: I recall running into a similar problem, I eventually scrapped the opengl dependency but it might be possible to wrap the whole thing up in a makeWrapper then pass in the opengl executable path for non-nixos systems into it. The reason, I believe, is that opengl is packaged as a static library and not a dynamic lib. On 14 Feb 2018 21:01, "Anthony Carrico" wrote: Any opengl program was going to have similar trouble since the libs are a function of the drivers which can't really be provided by Nix on non NixOS platforms. This situation was more of a reflection on the state of OpenGL than Nix in my opinion, but we ended up developing in a NixOs vm for this reason only. I don't remember what other changes I made, this was the biggest pain point. I did integrate with other foreign functions. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
Claes Wallin writes:
> On Sunday, February 11, 2018 at 9:43:34 PM UTC+8, stewart mackenzie wrote:
>>
>> Hello,
>>
>> We're partially through the development of a nix{os} utility which
>> transforms an info.rkt into a nix expression.
>>
>> https://github.com/clacke/racket2nix
>>
>> It'll be helpful if other nixers/racketers could contribute or test the
>> project!
>>
>
> Hi, Racketeers! I'm the one mainly working on this, and I could use some
> help right now. :-)
>
> I have a concrete problem, and I've been banging my head against this for a
> bit, so I hope someone has some insights to share.
This is great Claes, and as I said on IRC, I hope we can eventually
collaborate... as some others know I'm hoping to get more Racket
packages into Guix... which is like Nix, but written in Scheme!
But that work will probably build on experiences from this Nix work if I
get to it first at all (and it sounds like you might beat me to it
anyway) ;)
Thanks for working on this!
--
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Re: [racket-users] Re: racket2nix
Test posting, please ignore, sorry
On Monday, February 19, 2018 at 12:40:38 PM UTC-8, cwebber wrote:
>
> Claes Wallin writes:
>
> > On Sunday, February 11, 2018 at 9:43:34 PM UTC+8, stewart mackenzie
> wrote:
> >>
> >> Hello,
> >>
> >> We're partially through the development of a nix{os} utility which
> >> transforms an info.rkt into a nix expression.
> >>
> >> https://github.com/clacke/racket2nix
> >>
> >> It'll be helpful if other nixers/racketers could contribute or test the
> >> project!
> >>
> >
> > Hi, Racketeers! I'm the one mainly working on this, and I could use some
> > help right now. :-)
> >
> > I have a concrete problem, and I've been banging my head against this
> for a
> > bit, so I hope someone has some insights to share.
>
> This is great Claes, and as I said on IRC, I hope we can eventually
> collaborate... as some others know I'm hoping to get more Racket
> packages into Guix... which is like Nix, but written in Scheme!
> But that work will probably build on experiences from this Nix work if I
> get to it first at all (and it sounds like you might beat me to it
> anyway) ;)
>
> Thanks for working on this!
>
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Re: [racket-users] #lang rust
On 20/02/18 07:21, Neil Van Dyke wrote: > If someone is looking for a challenging and interesting `#lang` project... > > Build a `#lang rust`. https://www.rust-lang.org/ > +1 > You might first implement mapping the non-checking semantics to Racket > code (so that you can run valid Rust programs), and then later try to > implement all the checking (for detecting invalid Rust programs). > > Your big test would be bootstrapping the real Rust compiler. (You use > your Racket-based Rust language implementation to run the real Rust > compiler, to have the real compiler compile itself.) > This would be awesome but certainly a multi-year project for a single person I think. Also, there might be some trouble on understanding the rust grammar. I have in the past toyed with the idea of building a rust gcc frontend (previous attempts failed) but due to the lack of a formal grammar I gave up. Things might have changed since mid-2017 but I doubt it. One alternative to proceed without a formal grammar would be maybe to somehow use libparse from the rust project to parse the code and then use FFI to bring the structures into Racket. However, as a C/C++ replacement I love what Rust stands for so +1 (again!) for this project. -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
On Tuesday, February 20, 2018 at 4:40:38 AM UTC+8, cwebber wrote: > > This is great Claes, and as I said on IRC, I hope we can eventually > collaborate... as some others know I'm hoping to get more Racket > packages into Guix... which is like Nix, but written in Scheme! > But that work will probably build on experiences from this Nix work if I > get to it first at all (and it sounds like you might beat me to it > anyway) ;) > > Thanks for working on this! > It sounded on IRC that you're pretty busy, so yeah, I'll probably get there first. :-) Status update: racket2nix is now in a limited useful state! I'm able to build the drracket package without any error conditions occurring along the way, but: - The resulting drracket package is empty. :-D - I'm not actually building the packages, just installing them (raco pkg install --no-setup). - There is a lot of cleaning up to do in the nix expressions, the low-hanging fruit being e.g. redundant dependency listings -- drracket has over 1500 dependencies, but a simple sort -u on them reveals that they are actually only 135. - It probably doesn't put any stuff in .../bin . My next step is dogfooding racket2nix: Put the logic in a library, generate a thin wrapper that calls it, add rackunit tests, make a man page, etc. Hopefully this will teach me enough about packaging that I can go back and work toward a working drracket package. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] #lang rust
What about totally different approach to Rust and Racket interaction: Racket is trying to move to Chez Scheme. https://blog.racket-lang.org/2018/01/racket-on-chez-status.html The C part of Chez Scheme is about 16k lines. Translating (at least) some of that to Rust might be an interesing project. No guarantee that anyone will join, much less that it is a good idea. Kind regards: al_shopov На вт, 20.02.2018 г. в 12:32 ч. 'Paulo Matos' via Racket Users < racket-users@googlegroups.com> написа: > > > On 20/02/18 07:21, Neil Van Dyke wrote: > > If someone is looking for a challenging and interesting `#lang` > project... > > > > Build a `#lang rust`. https://www.rust-lang.org/ > > > > +1 > > > You might first implement mapping the non-checking semantics to Racket > > code (so that you can run valid Rust programs), and then later try to > > implement all the checking (for detecting invalid Rust programs). > > > > Your big test would be bootstrapping the real Rust compiler. (You use > > your Racket-based Rust language implementation to run the real Rust > > compiler, to have the real compiler compile itself.) > > > > This would be awesome but certainly a multi-year project for a single > person I think. > > Also, there might be some trouble on understanding the rust grammar. I > have in the past toyed with the idea of building a rust gcc frontend > (previous attempts failed) but due to the lack of a formal grammar I > gave up. Things might have changed since mid-2017 but I doubt it. > > One alternative to proceed without a formal grammar would be maybe to > somehow use libparse from the rust project to parse the code and then > use FFI to bring the structures into Racket. > > However, as a C/C++ replacement I love what Rust stands for so +1 > (again!) for this project. > > -- > Paulo Matos > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] #lang rust
On Wed, Feb 21, 2018 at 10:34:03AM +, Alexander Shopov wrote: > What about totally different approach to Rust and Racket interaction: > Racket is trying to move to Chez Scheme. > https://blog.racket-lang.org/2018/01/racket-on-chez-status.html > The C part of Chez Scheme is about 16k lines. > Translating (at least) some of that to Rust might be an interesing project. > No guarantee that anyone will join, much less that it is a good idea. > Kind regards: > al_shopov The interesting parrt would the integrating of Rust's garbage collector (yes, it has a concept of garbage collection for data declared to need it) with Racket's. -- hendrik -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] #lang rust
On Wed, 21 Feb 2018, 14:44 Hendrik Boom, wrote: > The interesting parrt would the integrating of Rust's garbage > collector (yes, it has a concept of garbage collection for data declared > to need it) with Racket's. > I understand you'd need the Custom Allocator which is (currently) only available on rust nightly which is a relatively fast moving target. /sjm > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Re: racket2nix
On 02/16/2018 04:32 AM, stewart mackenzie wrote: > Re opengl: I recall running into a similar problem, I eventually > scrapped the opengl dependency but it might be possible to wrap the > whole thing up in a makeWrapper then pass in the opengl executable path > for non-nixos systems into it. Thanks. That might require some (dynamic) probing. IIRC the OpenGL library/driver situation was different from distribution to distribution (and just needlessly confusing in general). Maybe someone has worked up a general solution to this particular problem, and if so Racket could adopt that. Amazingly, Nix has already solved many such weird issues. If this Racket/Nix effort goes forward, Racket users will probably need some guidance (and discipline) regarding foreign libraries. -- Anthony Carrico -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] #lang rust
On Wednesday, February 21, 2018 at 11:20:23 PM UTC+8, stewart mackenzie wrote: > > On Wed, 21 Feb 2018, 14:44 Hendrik Boom, > wrote: > >> The interesting parrt would the integrating of Rust's garbage >> collector (yes, it has a concept of garbage collection for data declared >> to need it) with Racket's. >> > > I understand you'd need the Custom Allocator which is (currently) only > available on rust nightly which is a relatively fast moving target. > >> Unless you use Racket with the conservative gc and let it figure things out? -- /c -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Are canvases stackable?
Is it possible to stack two (or more) canvases on top of one another. I'm working on a chess app and I don't want to draw individual squares under each piece. I would prefer to have a board canvas that doesn't change and a transparent canvas with pieces overlaying it. Is that possible? Is that the right approach or are there better alternatives? Thanks, David -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Are canvases stackable?
You want to use a pasteboard% for the chess table and snip% objects for the pieces. You can draw the board as the pasteboard background in the on-draw method. You will have to implement snip management in the pasteboard though because by default snips can just be dragged around and placed anywhere. There’s a racket game collection which might provide useful classes, but I have no experience with those. Best regards, Alex -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: Understanding 'curry'
On Tue, Feb 27, 2018 at 11:35 AM, David Storrs wrote: > Despite using it for a long time, I discovered today that I do not > understand 'curry', at least insofar as it applies to keyword > arguments. > >> (define (baz a b) b) >> (baz 8 9) > 9 > >> (curry baz 8) > # > >> ((curry baz 8) 9) > 9 > >> (define (foo a #:bar x) x) >> (foo 8 #:bar 9) > 9 > >> (curry foo #:bar 9) > # > > Up to this point I'm fine, but now my understanding derails and all is > confusion. > >> ((curry foo #:bar 9) 8) > # > > I expected it to yield 9 as it did in the original direct call. The > curry records the keyword argument and returns a function that takes > one positional argument; when that argument is supplied the original > foo function has all the arguments it needs so it should execute. > > Maybe if I apply the final curried proc as a thunk? > >> (((curry foo #:bar 8) 9)) > # > > Nope. > > What am I not understanding? For the record: I did check the docs <https://docs.racket-lang.org/reference/procedures.html> and this line informed my (incorrect) understanding: "The curry function provides limited support for keyworded functions: only the curry call itself can receive keyworded arguments to be propagated eventually to proc." -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
RE: [racket-users] Understanding 'curry'
curry itself is curried (which sometimes is puzzling) (define (foo a #:bar x) x) ((curry foo #:bar 9) 8) ; -> # ((curry curry foo #:bar 9) 8) ; -> 9 I hope others can explain this in detail. I can't. Jos -Original Message- From: racket-users@googlegroups.com [mailto:racket-users@googlegroups.com] On Behalf Of David Storrs Sent: martes, 27 de febrero de 2018 17:36 To: Racket Users Subject: [racket-users] Understanding 'curry' Despite using it for a long time, I discovered today that I do not understand 'curry', at least insofar as it applies to keyword arguments. > (define (baz a b) b) > (baz 8 9) 9 > (curry baz 8) # > ((curry baz 8) 9) 9 > (define (foo a #:bar x) x) > (foo 8 #:bar 9) 9 > (curry foo #:bar 9) # Up to this point I'm fine, but now my understanding derails and all is confusion. > ((curry foo #:bar 9) 8) # I expected it to yield 9 as it did in the original direct call. The curry records the keyword argument and returns a function that takes one positional argument; when that argument is supplied the original foo function has all the arguments it needs so it should execute. Maybe if I apply the final curried proc as a thunk? > (((curry foo #:bar 8) 9)) # Nope. What am I not understanding? -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Understanding 'curry'
On Tue, Feb 27, 2018 at 12:12 PM, Jos Koot wrote: > curry itself is curried (which sometimes is puzzling) > > (define (foo a #:bar x) x) > ((curry foo #:bar 9) 8) ; -> # > ((curry curry foo #:bar 9) 8) ; -> 9 > > I hope others can explain this in detail. > I can't. > > Jos > Madness! Madness, I say! Okay, it looks like I misunderstood what it meant by "The curry function provides limited support for keyworded functions: only the curry call itself can receive keyworded arguments to be propagated eventually to proc." It's currying the keyword argument *onto the curry function*, not onto the foo function. The result is a form of curry, not a form of foo. (define (bar a b) b) (curry bar 7) ...produces a version of bar that takes one argument and the other one is already set. (curry curry bar) ...produces a function that, when evaluated, will return a function that is the result of currying no arguments onto the function bar. (Which is equivalent to bar) Similarly: (define (foo a #:bar x) x) (curry curry foo #:bar 9) ...is creating a function that, when evaluated, will generate a function that is the result of currying the keyword argument+value '#:bar 9' onto foo. expects N arguments where N is the number of positional arguments expected by foo. It is not possible to generate directly, it needs to be done by creating and evaluating . Also, will not accept keyword arguments. (define (foo a #:bar x #:baz y) x) > (foo 7 #:bar 8 #:baz 9) 8 > (curry curry foo #:bar 8 #:baz 9) # > ((curry curry foo #:bar 8 #:baz 9) 7) 8 > ((curry curry foo #:bar 8) 7) ; application: required keyword argument not supplied ; procedure: foo ; required keyword: #:baz ; [,bt for context] > ((curry curry foo #:bar 8) 7 #:baz 9) ; application: procedure does not accept keyword arguments ; procedure: curried ; [,bt for context] That makes my brain hurt, but I think I get it. Thanks, Jos > > -Original Message- > From: racket-users@googlegroups.com [mailto:racket-users@googlegroups.com] > On Behalf Of David Storrs > Sent: martes, 27 de febrero de 2018 17:36 > To: Racket Users > Subject: [racket-users] Understanding 'curry' > > Despite using it for a long time, I discovered today that I do not > understand 'curry', at least insofar as it applies to keyword > arguments. > > > (define (baz a b) b) > > (baz 8 9) > 9 > > > (curry baz 8) > # > > > ((curry baz 8) 9) > 9 > > > (define (foo a #:bar x) x) > > (foo 8 #:bar 9) > 9 > > > (curry foo #:bar 9) > # > > Up to this point I'm fine, but now my understanding derails and all is > confusion. > > > ((curry foo #:bar 9) 8) > # > > I expected it to yield 9 as it did in the original direct call. The > curry records the keyword argument and returns a function that takes > one positional argument; when that argument is supplied the original > foo function has all the arguments it needs so it should execute. > > Maybe if I apply the final curried proc as a thunk? > > > (((curry foo #:bar 8) 9)) > # > > Nope. > > What am I not understanding? > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
RE: [racket-users] Understanding 'curry'
It breaks my brain, certainly. Glad to read you think you are getting to it. When you got it, explain to me, please, for I don't understand nothing of it. I just applied some trial and error to get to a point where I can use curry. (In fact I prefer to use my own curry (that is not curried, but neither workd with keyword arguments) My private curry gives ((curry list)) -> (), not a procedure. For me it remains a queston why curry has been made such as to give a procedure that in behaviour differs from a procedure produced by an application of a curried frunction. Jos _ From: David Storrs [mailto:david.sto...@gmail.com] Sent: martes, 27 de febrero de 2018 20:13 To: Jos Koot Cc: Racket Users Subject: Re: [racket-users] Understanding 'curry' On Tue, Feb 27, 2018 at 12:12 PM, Jos Koot wrote: curry itself is curried (which sometimes is puzzling) (define (foo a #:bar x) x) ((curry foo #:bar 9) 8) ; -> # ((curry curry foo #:bar 9) 8) ; -> 9 I hope others can explain this in detail. I can't. Jos Madness! Madness, I say! Okay, it looks like I misunderstood what it meant by "The curry function provides limited support for keyworded functions: only the curry call itself can receive keyworded arguments to be propagated eventually to proc." It's currying the keyword argument *onto the curry function*, not onto the foo function. The result is a form of curry, not a form of foo. (define (bar a b) b) (curry bar 7) ...produces a version of bar that takes one argument and the other one is already set. (curry curry bar) ...produces a function that, when evaluated, will return a function that is the result of currying no arguments onto the function bar. (Which is equivalent to bar) Similarly: (define (foo a #:bar x) x) (curry curry foo #:bar 9) ...is creating a function that, when evaluated, will generate a function that is the result of currying the keyword argument+value '#:bar 9' onto foo. expects N arguments where N is the number of positional arguments expected by foo. It is not possible to generate directly, it needs to be done by creating and evaluating . Also, will not accept keyword arguments. (define (foo a #:bar x #:baz y) x) > (foo 7 #:bar 8 #:baz 9) 8 > (curry curry foo #:bar 8 #:baz 9) # > ((curry curry foo #:bar 8 #:baz 9) 7) 8 > ((curry curry foo #:bar 8) 7) ; application: required keyword argument not supplied ; procedure: foo ; required keyword: #:baz ; [,bt for context] > ((curry curry foo #:bar 8) 7 #:baz 9) ; application: procedure does not accept keyword arguments ; procedure: curried ; [,bt for context] That makes my brain hurt, but I think I get it. Thanks, Jos -Original Message- From: racket-users@googlegroups.com [mailto:racket-users@ <mailto:racket-users@googlegroups.com> googlegroups.com] On Behalf Of David Storrs Sent: martes, 27 de febrero de 2018 17:36 To: Racket Users Subject: [racket-users] Understanding 'curry' Despite using it for a long time, I discovered today that I do not understand 'curry', at least insofar as it applies to keyword arguments. > (define (baz a b) b) > (baz 8 9) 9 > (curry baz 8) # > ((curry baz 8) 9) 9 > (define (foo a #:bar x) x) > (foo 8 #:bar 9) 9 > (curry foo #:bar 9) # Up to this point I'm fine, but now my understanding derails and all is confusion. > ((curry foo #:bar 9) 8) # I expected it to yield 9 as it did in the original direct call. The curry records the keyword argument and returns a function that takes one positional argument; when that argument is supplied the original foo function has all the arguments it needs so it should execute. Maybe if I apply the final curried proc as a thunk? > (((curry foo #:bar 8) 9)) # Nope. What am I not understanding? -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscribe@ <mailto:racket-users%2bunsubscr...@googlegroups.com> googlegroups.com. For more options, visit https://groups.google.com/d/ <https://groups.google.com/d/optout> optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Understanding 'curry'
On Tue, Feb 27, 2018 at 2:46 PM, Jos Koot wrote: > It breaks my brain, certainly. > Glad to read you think you are getting to it. > When you got it, explain to me, please, for I don't understand nothing of > it. > I just applied some trial and error to get to a point where I can use > curry. > (In fact I prefer to use my own curry (that is not curried, but > neither workd with keyword arguments) > My private curry gives ((curry list)) -> (), not a procedure. > For me it remains a queston why curry has been made such as to give a > procedure that in behaviour differs from a procedure produced by an > application of a curried frunction. > Jos > Oh, it's simple! When you curry curry your curried curry can have curried any sort of arguments but it can't curry keyword arguments, only positionals, so you need to curry curry in order to curry a keyword that you want to curry onto a non-curry function to produce a curried function. Stated in a less smart-alecky way: You cannot curry keyword arguments onto a function, unless that function is the curry function itself. I have no idea why it does that. Here's a series of items that clarified it for me. I suspect you get it at least as well as I do, but hopefully it will help someone else at some point: Welcome to Racket v6.11. > (define (pos-only a b) b) > (pos-only 7 8) 8 > (curry pos-only 7) # ; actual value is roughly (lambda (b) (pos-only 7 b)) > ((curry pos-only 7) 8) 8 > ((lambda (b) (pos-only 7 b)) 8) 8 > (curry curry pos-only 7) ; you can curry the 'curry' function. # ; roughly equivalent to (lambda args (apply (curry pos-only 7) args)) > (define (has-1-kw a #:foo b) b) > (has-1-kw 7 #:foo 8) 8 > (curry has-1-kw 7) ; you cannot curry a function with keyword arguments... ; application: required keyword argument not supplied ; procedure: has-1-kw ; required keyword: #:foo ; [,bt for context] > (curry curry has-1-kw) ; ...but you can curry the function 'curry', giving it a single argument that is a function. The function in question requires keyword arguments, but that's not relevant here. # > (curry curry #:foo 7) ; the 'curry' function can accept arbitrary keyword arguments # ; conceptually equivalent to (lambda (func . args) (apply curry func _ #:foo 7)) where _ will be replaced with more arguments later. That is NOT legal syntax, however. Recall that the 'curry' function takes a function (call it ) and returns a new function (call it ). In general, is not allowed to accept keyword arguments. The only exception to this is if is the curry function itself, in which case you're free to pass keywords. Why it's like this, I don't get any more than Jos does. > ---------- > *From:* David Storrs [mailto:david.sto...@gmail.com] > *Sent:* martes, 27 de febrero de 2018 20:13 > *To:* Jos Koot > *Cc:* Racket Users > *Subject:* Re: [racket-users] Understanding 'curry' > > > > On Tue, Feb 27, 2018 at 12:12 PM, Jos Koot wrote: > >> curry itself is curried (which sometimes is puzzling) >> >> (define (foo a #:bar x) x) >> ((curry foo #:bar 9) 8) ; -> # >> ((curry curry foo #:bar 9) 8) ; -> 9 >> >> I hope others can explain this in detail. >> I can't. >> >> Jos >> > > Madness! Madness, I say! > > Okay, it looks like I misunderstood what it meant by "The curry function > provides limited support for keyworded functions: only the curry call > itself can receive keyworded arguments to be propagated eventually to > proc." It's currying the keyword argument *onto the curry function*, not > onto the foo function. The result is a form of curry, not a form of foo. > > (define (bar a b) b) > (curry bar 7) > ...produces a version of bar that takes one argument and the other one is > already set. > > (curry curry bar) > ...produces a function that, when evaluated, will return a function > that is the result of currying no arguments onto the function bar. > (Which is equivalent to bar) > > Similarly: > > (define (foo a #:bar x) x) > (curry curry foo #:bar 9) > ...is creating a function that, when evaluated, will generate a > function that is the result of currying the keyword argument+value > '#:bar 9' onto foo. expects N arguments where N is the number of > positional arguments expected by foo. It is not possible to generate > directly, it needs to be done by creating and evaluating . Also, > will not accept keyword arguments. > > (define (foo a #:bar x #:baz y) x) > > (foo 7 #:bar 8 #:baz 9) > 8 > > > (curry curry foo #:bar 8 #:baz 9) > # > > > ((curry curry foo #:bar 8 #:baz 9)
RE: [racket-users] Understanding 'curry'
You are right, I think. Thanks. _ From: David Storrs [mailto:david.sto...@gmail.com] Sent: martes, 27 de febrero de 2018 22:29 To: Jos Koot Cc: Racket Users Subject: Re: [racket-users] Understanding 'curry' On Tue, Feb 27, 2018 at 2:46 PM, Jos Koot wrote: It breaks my brain, certainly. Glad to read you think you are getting to it. When you got it, explain to me, please, for I don't understand nothing of it. I just applied some trial and error to get to a point where I can use curry. (In fact I prefer to use my own curry (that is not curried, but neither workd with keyword arguments) My private curry gives ((curry list)) -> (), not a procedure. For me it remains a queston why curry has been made such as to give a procedure that in behaviour differs from a procedure produced by an application of a curried frunction. Jos Oh, it's simple! When you curry curry your curried curry can have curried any sort of arguments but it can't curry keyword arguments, only positionals, so you need to curry curry in order to curry a keyword that you want to curry onto a non-curry function to produce a curried function. Stated in a less smart-alecky way: You cannot curry keyword arguments onto a function, unless that function is the curry function itself. I have no idea why it does that. Here's a series of items that clarified it for me. I suspect you get it at least as well as I do, but hopefully it will help someone else at some point: Welcome to Racket v6.11. > (define (pos-only a b) b) > (pos-only 7 8) 8 > (curry pos-only 7) # ; actual value is roughly (lambda (b) (pos-only 7 b)) > ((curry pos-only 7) 8) 8 > ((lambda (b) (pos-only 7 b)) 8) 8 > (curry curry pos-only 7) ; you can curry the 'curry' function. # ; roughly equivalent to (lambda args (apply (curry pos-only 7) args)) > (define (has-1-kw a #:foo b) b) > (has-1-kw 7 #:foo 8) 8 > (curry has-1-kw 7) ; you cannot curry a function with keyword arguments... ; application: required keyword argument not supplied ; procedure: has-1-kw ; required keyword: #:foo ; [,bt for context] > (curry curry has-1-kw) ; ...but you can curry the function 'curry', giving > it a single argument that is a function. The function in question requires keyword arguments, but that's not relevant here. # > (curry curry #:foo 7) ; the 'curry' function can accept arbitrary keyword > arguments # ; conceptually equivalent to (lambda (func . args) (apply curry func _ #:foo 7)) where _ will be replaced with more arguments later. That is NOT legal syntax, however. Recall that the 'curry' function takes a function (call it ) and returns a new function (call it ). In general, is not allowed to accept keyword arguments. The only exception to this is if is the curry function itself, in which case you're free to pass keywords. Why it's like this, I don't get any more than Jos does. _ From: David Storrs [mailto:david.sto...@gmail.com] Sent: martes, 27 de febrero de 2018 20:13 To: Jos Koot Cc: Racket Users Subject: Re: [racket-users] Understanding 'curry' On Tue, Feb 27, 2018 at 12:12 PM, Jos Koot wrote: curry itself is curried (which sometimes is puzzling) (define (foo a #:bar x) x) ((curry foo #:bar 9) 8) ; -> # ((curry curry foo #:bar 9) 8) ; -> 9 I hope others can explain this in detail. I can't. Jos Madness! Madness, I say! Okay, it looks like I misunderstood what it meant by "The curry function provides limited support for keyworded functions: only the curry call itself can receive keyworded arguments to be propagated eventually to proc." It's currying the keyword argument *onto the curry function*, not onto the foo function. The result is a form of curry, not a form of foo. (define (bar a b) b) (curry bar 7) ...produces a version of bar that takes one argument and the other one is already set. (curry curry bar) ...produces a function that, when evaluated, will return a function that is the result of currying no arguments onto the function bar. (Which is equivalent to bar) Similarly: (define (foo a #:bar x) x) (curry curry foo #:bar 9) ...is creating a function that, when evaluated, will generate a function that is the result of currying the keyword argument+value '#:bar 9' onto foo. expects N arguments where N is the number of positional arguments expected by foo. It is not possible to generate directly, it needs to be done by creating and evaluating . Also, will not accept keyword arguments. (define (foo a #:bar x #:baz y) x) > (foo 7 #:bar 8 #:baz 9) 8 > (curry curry foo #:bar 8 #:baz 9) # > ((curry curry foo #:bar 8 #:baz 9) 7) 8 > ((curry curry foo #:bar 8) 7) ; application: required keyword argument not supplied ; procedure: foo ; required keyword: #:baz ; [,
[racket-users] Re: Understanding 'curry'
Thanks everyone for the headache. I think I'll stick to the `fancy-app` package and reserve curry for adventurous dinner outings. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Debugging racket applications
Hi, I have been using Greg's racket mode and racket on the command line to start my application. One of the most frustrating/infuriating things about full time racket programming at the moment is debugging. For example, here's a run of my program: $ racket /var/tmp/lt15198411601519841160715/0/driver-0.rkt <: contract violation expected: real? given: #f argument position: 2nd other arguments...: 1 context...: /home/pmatos/Projects/lt/lt/stochastic.rkt:179:26 /var/tmp/lt15198411601519841160715/0/driver-0.rkt: [running body] The context is quite unhelpful. Like 179 of stochastic.rkt is: (lambda (candidate) There's no call to '<' anywhere nearby. DrRacket is not that much more helpful. If it helps, I currently setup my project as: raco pkg install --auto --link raco setup --tidy --check-pkg-deps --unused-pkg-deps --pkgs lt Is there anything I can try to improve backtrace generation? Kind regards, -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: #lang rust
FWIW at one point I began trying to translate something similar to Rust in Redex, but I haven't made progress on it in a few months. https://github.com/iitalics/rust-redex On Tuesday, February 20, 2018 at 1:21:46 AM UTC-5, Neil Van Dyke wrote: > > If someone is looking for a challenging and interesting `#lang` project... > > Build a `#lang rust`. https://www.rust-lang.org/ > > You might first implement mapping the non-checking semantics to Racket > code (so that you can run valid Rust programs), and then later try to > implement all the checking (for detecting invalid Rust programs). > > Your big test would be bootstrapping the real Rust compiler. (You use > your Racket-based Rust language implementation to run the real Rust > compiler, to have the real compiler compile itself.) > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] racket2nix status report
Progress! It's still full of workarounds and doesn't do everything I'd like it to, but it does package and run itself successfully! Maybe I will call it 0.1 some time this month and put it into the racket package space, but for now you can try it out by simply cloning https://github.com/fractalide/racket2nix/ and running ./racket2nix and see what kind of nix expression pops out on stdout. I'm going to go ahead according to "better to ask for forgiveness than for permission" and put up in the README that people are welcome to ask questions about racket2nix here on racket-users. I don't expect huge traffic, but if anybody objects, I'll remove it promptly. -- /c -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] struct question
On Wed, Mar 7, 2018 at 9:27 PM, Kevin Forchione wrote: > Hi guys, > Can we associate more than 1 generic with a struct? Something like: > > (struct foo (..) #:methods gen:bar [] gen:baz [] …) > > > Yes, except it's: (struct foo (..) #:methods gen:bar [] #:methods gen:baz [] ...) -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] "Site not secure"
Hi, I tried to grab the latest racket version from download.racket-lang.org and chrome and edge tell me the certificate of the site at mirror.racket-lang.org is not yet valid or expired. It's no problem as I found a mirror with a valid certificate, but I guess you'll want to renew the certificate. Cheers, tim -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Struct initialization?
On Fri, Mar 9, 2018 at 9:35 PM, Kevin Forchione wrote: > Is it possible to initialize a struct field based on values from > previously defined fields? Something equivalent to let* where > > >(struct foo (A B C)) > >(foo 1 2) would produce (foo 1 2 3) for example? > > > As far as I know, the only way to do this is to write your own function that calls the struct constructor. You can do this in a module, and only export your constructor, instead of the default struct constructor. If you want the constructor and the match expander to use the same identifier, then you need to do a bit more work. For example: ``` #lang racket/base (require racket/match (for-syntax racket/base syntax/transformer)) (struct foo* (A B C)) (define (foo a b) (foo* a b (+ a b))) (define-match-expander $foo (syntax-rules () [(foo a b c) (foo* a b c)]) (make-variable-like-transformer #'foo)) (provide (rename-out [$foo foo] [foo*-A foo-A] [foo*-B foo-B] [foo*-C foo-C]))) ``` Of course, even here, an instance will print as #. You can implement gen:custom-write to fix that. There might be a better way to do this, but this is what I've used in the past. - Jon -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Struct initialization?
You can also set! the extra constructor #lang racket (struct foo [a b c] #:extra-constructor-name -foo #:transparent) (define ((foo* make-foo) a b) (make-foo a b (+ a b))) (set! -foo (foo* -foo)) (foo 1 2) ; -> (foo 1 2 3) (match (foo 1 2) [(foo _ _ c) c]) ; -> 3 However I usually just provide a custom make-X function as the only constructor. If you're hiding initialization details through the constructor it seems a bit odd to not hide these details in the match expander. So if you really want full encapsulation you should write the match expander as well. But in practice that's usually overkill. On Friday, March 9, 2018 at 10:24:00 PM UTC-5, Jon Zeppieri wrote: > > > > On Fri, Mar 9, 2018 at 9:35 PM, Kevin Forchione > wrote: > >> Is it possible to initialize a struct field based on values from >> previously defined fields? Something equivalent to let* where >> >> >(struct foo (A B C)) >> >(foo 1 2) would produce (foo 1 2 3) for example? >> >> >> As far as I know, the only way to do this is to write your own function > that calls the struct constructor. You can do this in a module, and only > export your constructor, instead of the default struct constructor. > > If you want the constructor and the match expander to use the same > identifier, then you need to do a bit more work. For example: > > ``` > #lang racket/base > > (require racket/match > (for-syntax racket/base > syntax/transformer)) > > (struct foo* (A B C)) > > (define (foo a b) > (foo* a b (+ a b))) > > (define-match-expander $foo > (syntax-rules () > [(foo a b c) (foo* a b c)]) > (make-variable-like-transformer #'foo)) > > (provide (rename-out [$foo foo] > [foo*-A foo-A] > [foo*-B foo-B] > [foo*-C foo-C]))) > ``` > > Of course, even here, an instance will print as #. You can implement > gen:custom-write to fix that. > > There might be a better way to do this, but this is what I've used in the > past. > > - Jon > > > > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Style guide linter
Hi, I found the style guide a really great idea and generally very useful (although it's a shame the lack of content on the section of classes). I have started a small script to check source code style based on the style guide. Simple things like spaces at the end of lines, lack of newline at the end of file, lines longer than 102 chars etc. However, I would like to know if there's anything already out there before I try to get more complex features implemented. Kind regards, -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Output Port Shenanigans
Hello, everyone! I'm trying to get an output port to display text to both the error port and a text% object every time there's an error or an `eprintf` is called. Now, I have already accomplished this by using `make-output-port`, but I had decided to try and use `open-output-text-editor` instead just for gits and shiggles. In the procedure documentation it shows that it takes a lambda labeled "special filter", so I figured I'd hijack this lambda to then fprintf to the error port, but for whatever reason it seems that all printing that is done from inside that special filter's scope is sent I have tried the following, but without any success: (define old-out (current-output-port)) ; now inside special filter's scope (lambda (s) (fprintf old-out "foo") s) There must be something I'm missing, but there's not much in the docs that would help me. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Struct initialization?
I've written an experimental macro `structure` that tries to make it convenient to write custom wrappers for the constructor and the match expander that use the name of the struct: http://docs.racket-lang.org/adjutor/Experimental.html#%28form._%28%28lib._adjutor%2Fmain..rkt%29._structure%29%29 If you're interested in doing something like that as a one-off, the implementation is here <https://github.com/LiberalArtist/adjutor/blob/master/structure.rkt>. Basically the approach is to use #:name and #:constructor-name to avoid binding the name of the struct (which is still used for printing and error reporting), define the actual constructor wrapper function you want, then to define-syntax the name of the struct to a compile-time data structure implementing prop:procedure, prop:struct-info, and prop:match-expander (unless you want the default match behavior). That sounds a little more complicated than it is: here's an example that doesn't override the default match behavior. #lang racket (require (for-syntax racket/struct-info syntax/transformer )) (begin-for-syntax (struct info-record (info macro) #:property prop:procedure (struct-field-index macro) #:property prop:struct-info (λ (this) (info-record-info this (struct foo (A B C) #:transparent #:name foo-transformer #:constructor-name raw-make-foo) (define (make-foo A B) (raw-make-foo A B (+ A B))) (define-syntax foo (info-record (extract-struct-info (syntax-local-value #'foo-transformer)) (make-variable-like-transformer #'make-foo))) All of that said, in practice, I haven't found myself reaching for my `structure` macro as frequently as I expected to when I wrote it. Most of the cases seem to fall into one of two categories. If I'm writing a trivial script, I usually find it sufficient to follow the convention of writing a constructor wrapper named `make-foo`. On the other hand, in a larger project, it becomes reasonable to use the module system to manage renaming and encapsulation, and typically I have a bunch of data-structures that I want to handle in a consistent, project-specific way. -Philip On Sat, Mar 10, 2018 at 1:19 AM, Milo Turner wrote: > You can also set! the extra constructor > > #lang racket > > (struct foo [a b c] > #:extra-constructor-name -foo > #:transparent) > > (define ((foo* make-foo) a b) > (make-foo a b (+ a b))) > > (set! -foo (foo* -foo)) > > (foo 1 2) ; -> (foo 1 2 3) > (match (foo 1 2) > [(foo _ _ c) c]) ; -> 3 > > However I usually just provide a custom make-X function as the only > constructor. If you're hiding initialization details through the > constructor it seems a bit > odd to not hide these details in the match expander. So if you really want > full encapsulation you should write the match expander as well. But in > practice > that's usually overkill. > > On Friday, March 9, 2018 at 10:24:00 PM UTC-5, Jon Zeppieri wrote: > >> >> >> On Fri, Mar 9, 2018 at 9:35 PM, Kevin Forchione wrote: >> >>> Is it possible to initialize a struct field based on values from >>> previously defined fields? Something equivalent to let* where >>> >>> >(struct foo (A B C)) >>> >(foo 1 2) would produce (foo 1 2 3) for example? >>> >>> >>> As far as I know, the only way to do this is to write your own function >> that calls the struct constructor. You can do this in a module, and only >> export your constructor, instead of the default struct constructor. >> >> If you want the constructor and the match expander to use the same >> identifier, then you need to do a bit more work. For example: >> >> ``` >> #lang racket/base >> >> (require racket/match >> (for-syntax racket/base >> syntax/transformer)) >> >> (struct foo* (A B C)) >> >> (define (foo a b) >> (foo* a b (+ a b))) >> >> (define-match-expander $foo >> (syntax-rules () >> [(foo a b c) (foo* a b c)]) >> (make-variable-like-transformer #'foo)) >> >> (provide (rename-out [$foo foo] >> [foo*-A foo-A] >> [foo*-B foo-B] >> [foo*-C foo-C]))) >> ``` >> >> Of course, even here, an instance will print as #. You can >> implement gen:custom-write to fix that. >> >> There might be a better way to do this, but this is what I've used in the >> past. >> >> - Jon >> >> >> >> >> -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Incorrect error reporting
Hello,
I was trying to understand the imap module so I created the following
script called main.rkt inside a src/ folder.
The file looks like this:
#lang racket/base
(require racket/function
net/imap)
(define (start-server user pass host port)
(define-values (conn total new)
(parameterize ([imap-port-number port])
(imap-connect host user pass "INBOX" #:try-tls? #true)))
(dynamic-wind
(void)
(thunk
(let loop ()
(imap-noop conn)
(define unseen (imap-unseen conn))
(printf "unseen: ~a~n" unseen)
(loop)))
(thunk
(imap-disconnect conn
(module+ main
(require racket/cmdline)
(define hostname (make-parameter "localhost"))
(define port (make-parameter "465"))
(define password (make-parameter #f))
(define username
(command-line
#:program "s10-tryout server"
#:once-each
[("-h" "--hostname") h
"Hostname (optional)"
(hostname h)]
[("-p" "--port") p
"Port (optional)"
(port p)]
[("--password") pass
"Password (optional)"
(password pass)]
#:args (user)
user))
(unless (password)
(password (read)))
(start-server (username) (password) (hostname) (port)))
The most interesting thing about this is how it fails (surely due to
some error of mine), but without actually helping much even when called
with errortrace:
$ racket -l errortrace -t src/main.rkt
parse-command-line: expected argument of type ; given:
'((once-each (("-h" "--hostname")
# (("Hostname (optional)") "h"))
(("-p" "--port") # (("Port
(optional)") "p")) (("--password")
# (("Passw...
errortrace...:
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:199:13:
(define username (command-line #:program "s10-tryout server" #:once-each
(("-h" ) h ) (() ) () ))
context...:
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:266:10:
for-loop
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:257:4:
for-loop
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:251:2:
for-loop
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:229:0:
parse-command-line10
(submod /home/pmatos/Projects/s10-tryout/src/main.rkt main): [running
body]
This is Racket 6.12. The error message complains about a
parse-command-line which I never called. Then the type in the message:
is not very useful either if you do not understand the inner
working of parse-command-line.
The most surprising thing is that errortrace complains about:
/home/pmatos/installs/racket-6.12/collects/racket/cmdline.rkt:199:13:
(define username (command-line #:program "s10-tryout server" #:once-each
(("-h" ) h ....) ((....) ) () ))
But the expression (define username...) is on line 30 of main.rkt, not
on line 199 of cmdline.rkt.
Should this be reported as a bug?
--
Paulo Matos
--
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[racket-users] Parameterized Redex models
Hi, Papers often define parameterized metafunctions, reduction relations and judgment forms, and when I model them in PLT Redex, I reach for Racket parameters; but the resulting definitions are impure, and they invalidate Redex’s cache. I first present three workarounds, none of which are satisfactory, and then I propose two new Redex features that address this issue. PROBLEM To ground our conversation, let us consider an example: in Abstracting Abstract Machines (AAM),¹ page 726, we find the metafunction ‘tick’, which takes the ‘k’ first elements of the list ‘(e : t)’.² The ‘k’ in question is not an explicit argument of ‘tick’, but an analysis-wide parameter that is in scope and remains the same for definitions across several pages. To capture this intent, the following is a Redex model in which ‘k’ is a Racket parameter: #lang racket/base (require redex/reduction-semantics racket/list) (define k (make-parameter 0)) (define-language L [e ::= any] [t ::= [e ...]]) (define-metafunction L tick : e _ _ _ t -> t [(tick e _ _ _ t) ,(take (cons (term e) (term t)) (k))]) There is a problem with this definition, though, because ‘tick’ is impure—it relies on the mutable external state of ‘k’—and Redex caches metafunction applications: (term (tick a _ _ _ [])) '() (parameterize ([k 1]) (term (tick b _ _ _ []))) '(b) (parameterize ([k 1]) (term (tick a _ _ _ []))) '() The first two interactions illustrate the desired behavior: on the first, the ‘a’ is discarded because it overflows the default maximum list size ‘k = 0’; on the second, we bump ‘k = 1’ and ‘tick’ returns the list containing ‘b’. But things go wrong in the third interaction, when we try again to add ‘a’ to the empty list, this time with ‘k = 1’: Redex has cached the previous answer, so ‘tick’ wrongly discards ‘a’. WORKAROUNDS Workaround 1: Disable the Cache We set ‘caching-enabled? = #f’ whenever we parameterize ‘k’. This deteriorates performance. Workaround 2: Thread the Parameter Don’t have ‘k’ as a Racket parameter, and modify every definition to propagate ‘k’ as an argument. This clutters the model and sets it apart from the version on the paper. Workaround 3: Use a macro #lang racket/base (require (for-syntax racket/base racket/syntax) syntax/parse/define redex/reduction-semantics racket/list syntax/parse/define) (define-syntax-parser analysis [(_ k:integer) (with-syntax ([L (format-id #'k "L~a" (syntax-e #'k))] [tick (format-id #'k "tick~a" (syntax-e #'k))]) #'(begin (define-language L [e ::= any] [t ::= [e (... ...)]]) (define-metafunction L tick : e _ _ _ t -> t [(tick e _ _ _ t) ,(take (cons (term e) (term t)) k)])))]) We can instantiate different analyses for our choice of ‘k’: (analysis 0) (analysis 1) (term (tick0 a _ _ _ [])) '() (term (tick1 b _ _ _ [])) '(b) (term (tick1 a _ _ _ [])) '(a) This has many issues: it is harder to read and write; it requires escaping ellipses (see ‘(... ...)’ above); it binds the name ‘k’ in all contexts, including undesirable ones, for example, ‘(term k)’; it may break typesetting; it insists that ‘k’ is a literal number, not an expression that evaluates to a number; and it may be bad for compilation performance. Some of these issues are solved by writing even more incantations, but not all. SOLUTIONS Currently, I’m using Workaround 1, disabling the cache, but I wish for a lighter hammer. The simplest thing that comes to mind is a way for me to flush Redex’s cache when I parameterize ‘k’. This would be a good compromise: I’d still write a simple and correct model, and I’d leverage at least some of the performance benefits of caching. Unfortunately, cache invalidation continues to be one of the *hard problems* in computer science. I tried to disable and reenable the cache. I tried to ‘set-cache-size!’ to a low number and then back again. Nothing worked. Going further, we could introduce a ‘define-metaparameter’ form to Redex. A metaparameter is parameterizeable like a Racket parameter, but we can use it like a regular term in Redex definitions and the cache is aware of it. * * * Thoughts are appreciated. Is there a better way to accomplish my goal? Is it a valid thing to want in the first place? Parametrically confused, Leandro. * * * ¹ Van horn, David, and Matthew Might. 2012. “Systematic Abstraction of Abstract Machines.” J. Funct. Program. 22 (4–5): 705–746. https://doi.org/10.1017/S0956796812000238. ² Similar to ‘take’ from ‘racket/list’. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to rac
[racket-users] struct-copy question
Hi guys, I’ve noticed that struct-copy doesn’t appear to work when fields are defined with #:auto. So this leads to my question, which may not be answerable since it would presumably be used to fix struct-copy, but is there a way to retrieve a list of struct fields for a struct? I have a feeling there is some macro work going on and that the struct isn’t really “aware” of its field names. If that’s the case, wouldn’t it be interesting if the macro included building a function that would return these names as a symbols list? :) Thanks, Kevin -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Prefab and mutable
Hi, I was quite surprised by a 'feature' of prefab mutable structures: #lang racket (struct f (a b) #:prefab #:mutable) (place-message-allowed? (f 1 2)) (place-message-allowed? #s(f 1 2)) I was expecting both to return true but to my amazement it was not the case. The one created with #s(...) returned true while the other returned false. This is surprising because I thought I had read everything about prefabs and never seen this distinction being discussed. Any reasons for this to happen? -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Prefab and contracts
Hello, In a similar comment to my previous thread, I am yet again surprised at this: a.rkt: #lang racket (provide (struct-out foo)) (struct foo (a b) #:prefab) b.rkt: #lang racket (require "a.rkt") (place-message-allowed? (foo 1 2)) This works! However, try to provide in a.rkt foo like this: (provide (contract-out (struct foo ((a integer?) (b integer?) Suddenly you get: #f Here's the even more confusing part: (define-values (pch1 pch2) (place-channel)) (place-channel-put pch1 (foo 1 2)) This will result in: place-channel-put: value not allowed in a message value: '#s(foo 1 2) message: '#s(foo 1 2) This will drive you mad because if you copy the message textual representation: (place-channel-put pch1 '#s(foo 1 2)) then it works. What's the reason for this discrepancy? There's no mentioning of #:prefab in contract-out documentation. Regards, -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Windows Foreign Libraries
Really silly question but I was using the rsvg package with racket/gui on Linux and everything was working fine. I moved the code over to windows to try it out (after installing the rsvg package there) and it's complaining that librsvg-2.2.dll is missing. I've now tried two separate .dll files in my code directory (one that was from the official gnome ftp) and racket throws an error that ($1 is not a valid Win32 application) when trying to call (ffi-lib) on it. Now I'm going to try building the .dll myself, but I'm wondering if it's possible after I've got a .dll that works if you can somehow connect it with the rsvg package so when I compile for distribution in DrRacket it automatically includes the .dll I have. It pretty much already does this for all the other gnome libraries racket/gui uses, and it'd be much easier than having to manually add it to the libs after it's done compiling. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] a matrix question
hi, I'm trying out matrices (without typed racket, though I read the performance caveat -- I'm not worried about performance at the moment) and am trying to find the best idioms for a small function I'd like to build. Q1: is there an elegant away to assemble a matrix column-wise? (my first draft solution is to read one col-matrix and write cell by cell into a destination (mutable) matrix); my preference would be to use immutable items, but that's secondary to elegance at this point. cheers, Tim -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Struct general question
In another thread on structs it was confirmed that structs are in essence a vector with some fancy bindings associated. But there must be more going on, for instance, the definition (struct foo (A B)) creates a function foo that when applied does not print like a vector. Is there any documentation instructs that does into the details of what they are and are doing under the hood? Kevin -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Profiling places
On 27/03/18 14:55, 'Paulo Matos' via Racket Users wrote: > > 1. setup a profile command line argument that's passed to places-profile.rkt > 2. send a flag indicating if we need profiling in any-double? > 3. then use profile-thunk on the function if profiling is required, or > nothing if profiling is not required. > I have attempted this: ;; places-profile.rkt #lang racket (define (main) (define p (dynamic-place "any-double.rkt" 'place-entry)) ;; enable profiling (place-channel-put p #t) (for ([i (in-range 1000)]) (define l (build-list (random 1) (lambda (_) (random 100 (place-channel-put p l) (place-channel-get p)) (place-kill p)) (main) ;; any-double.rkt #lang racket (require profile) (require profile/render-text) (provide place-entry) (define (any-double? l) (for/or ([i (in-list l)]) (for/or ([i2 (in-list l)]) (= i2 (* 2 i) (define (place-entry ch) (define profile? (place-channel-get ch)) (profile-thunk (thunk (let loop () (define l (place-channel-get ch)) (define l-double? (any-double? l)) (place-channel-put ch l-double?) (loop))) #:periodic-renderer (list 4 render) #:use-errortrace? #t #:threads #t)) Unfortunately, every 4 secs I see: Profiling results - Total cpu time observed: 185393ms (out of 188238ms) Number of samples taken: 3727 (once every 50ms) Caller Idx TotalSelfName+srcLocal% ms(pct) ms(pct) Callee Absolutely no results. Why? Also, if I reduce the number of iterations in places-profile.rkt to 1000, and remove the periodic-render, there's absolutely no output from the profiler. Is this related with the killing of the place via place-kill? Is there a nice way to kill a place and still preserve profiling information? -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Profiling places
On Tue, 27 Mar 2018 07:55:08 -0500, 'Paulo Matos' via Racket Users wrote: > > I was trying to confirm my suspicion that profile needs to be manually > setup in each place for profiling. Right. Each place has its own separate runtime, and the profile only spans a single runtime. > Is this a possibility or is there something out there to make this > easier? Also, profile-thunk says that: > "To track all threads, specify a non-#f value for the threads? > argument―this will execute the computation in a fresh custodian, and > keep track of all threads under this custodian." > > But what happens if the place itself creates its own custodian to launch > threads? In this case, thread refers to Racket's concurrency mechanism; this is unrelated to places. On Tue, 27 Mar 2018 08:15:19 -0500, 'Paulo Matos' via Racket Users wrote: > > > > On 27/03/18 14:55, 'Paulo Matos' via Racket Users wrote: > > > > 1. setup a profile command line argument that's passed to places-profile.rkt > > 2. send a flag indicating if we need profiling in any-double? > > 3. then use profile-thunk on the function if profiling is required, or > > nothing if profiling is not required. > > > > I have attempted this: > [...] I get profiling information (including periodic reports) when I disable errortrace mode in `profile-thunk`. The errortrace mode requires the use of the errortrace compile-handler, without which there's nothing for the profiler to observe. `raco profile --use-errortrace` sets it, as does `racket -l errortrace -t places-profile.rkt`. However, neither of those work on your example. Could places be interfering with the compile-handler? Vincent -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Profiling places
On 27/03/18 17:18, Vincent St-Amour wrote: > On Tue, 27 Mar 2018 07:55:08 -0500, > 'Paulo Matos' via Racket Users wrote: >> >> I was trying to confirm my suspicion that profile needs to be manually >> setup in each place for profiling. > > Right. Each place has its own separate runtime, and the profile only > spans a single runtime. > >> Is this a possibility or is there something out there to make this >> easier? Also, profile-thunk says that: >> "To track all threads, specify a non-#f value for the threads? >> argument―this will execute the computation in a fresh custodian, and >> keep track of all threads under this custodian." >> >> But what happens if the place itself creates its own custodian to launch >> threads? > > In this case, thread refers to Racket's concurrency mechanism; this is > unrelated to places. > I understand that, what I meant was that I was wondering what would happen (haven't tried it yet) if the place spawned by `dynamic-place` creates a new custodian and uses that to create new threads. Would profiling through the place, with #:threads #t, still profile the threads? -- maybe I need to create an example. > On Tue, 27 Mar 2018 08:15:19 -0500, > 'Paulo Matos' via Racket Users wrote: >> >> >> >> On 27/03/18 14:55, 'Paulo Matos' via Racket Users wrote: >>> >>> 1. setup a profile command line argument that's passed to places-profile.rkt >>> 2. send a flag indicating if we need profiling in any-double? >>> 3. then use profile-thunk on the function if profiling is required, or >>> nothing if profiling is not required. >>> >> >> I have attempted this: >> [...] > > I get profiling information (including periodic reports) when I disable > errortrace mode in `profile-thunk`. > > The errortrace mode requires the use of the errortrace compile-handler, > without which there's nothing for the profiler to observe. > > `raco profile --use-errortrace` sets it, as does `racket -l errortrace > -t places-profile.rkt`. However, neither of those work on your example. > > Could places be interfering with the compile-handler? > True, I can confirm that. I will open an issue on this. I have no idea how the internals of these things work so not sure what could be happening here. Maybe Matthew knows? -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Profiling places
On 28/03/18 10:23, 'Paulo Matos' via Racket Users wrote: > True, I can confirm that. I will open an issue on this. Done #2019. https://github.com/racket/racket/issues/2019 -- Paulo Matos -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Profiling places
Thanks! I've commented there. Vincent On Wed, 28 Mar 2018 03:27:11 -0500, 'Paulo Matos' via Racket Users wrote: > > > > On 28/03/18 10:23, 'Paulo Matos' via Racket Users wrote: > > True, I can confirm that. I will open an issue on this. > > Done #2019. > https://github.com/racket/racket/issues/2019 > > -- > Paulo Matos > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: Understanding 'curry'
It's very very easy. The "curry" is from functional languages(Haskell,
OCaml, F#, ...).
The concept of curry is powerful when the following function form:
(function-name option-argument input-argument)
For example, we think about 2htdp/image.
#lang racket
(require 2htdp/image)
(overlay/align/offset
"left" "top"
(circle 30 "solid" "green yellow")
0 0
(overlay/align/offset
"left" "bottom"
(circle 30 "solid" "khaki")
10 0
(overlay/align/offset
"right" "top"
(circle 30 "solid" "orchid")
0 10
(overlay/align/offset
"right" "bottom"
(circle 30 "solid" "cornflowerblue")
-10 -10
(star-polygon 20 20 3 "solid" "navy")
In Lisp Programming, it prefer to indent radically. Therefore, we introduce
the "thread macro".
; thread macro (function)
(define (~> init . procs)
(foldl (lambda (proc arg) (proc arg))
init
procs))
(~> (star-polygon 20 20 3 "solid" "navy")
(lambda (image)
(overlay/align/offset "right" "bottom"
(circle 30 "solid" "cornflowerblue")
-10 -10
image))
(lambda (image)
(overlay/align/offset "right" "top"
(circle 30 "solid" "orchid")
0 10
image))
(lambda (image)
(overlay/align/offset "left" "bottom"
(circle 30 "solid" "khaki")
10 0
image))
(lambda (image)
(overlay/align/offset "left" "top"
(circle 30 "solid" "green yellow")
0 0
image)))
For more simple discription, we use curry instead of lambda.
(~> (star-polygon 20 20 3 "solid" "navy")
(curry overlay/align/offset "right" "bottom"
(circle 30 "solid" "cornflowerblue")
-10 -10)
(curry overlay/align/offset "right" "top"
(circle 30 "solid" "orchid")
0 10)
(curry overlay/align/offset "left" "bottom"
(circle 30 "solid" "khaki")
10 0)
(curry overlay/align/offset "left" "top"
(circle 30 "solid" "green yellow")
0 0))
Thanks,
Haruo
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[racket-users] Re: Understanding 'curry'
I'm sorry for my mistake. [Wrong] Thread Macro [Right] Threading Macro Threading macros are provided by Racket Package System and its documentation is included in Racket Document. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: Understanding 'curry'
Curry is from functional languages(Haskell, OCaml, F#, ...).
Curry is the one of abbreviation of labmda.
But, curry is NOT usable for racket's threading macros.
#lang racket
(require threading)
(require 2htdp/image)
(~> (star-polygon 20 20 3 "solid" "navy")
(overlay/align/offset "right" "bottom"
(circle 30 "solid" "cornflowerblue")
-10 -10 _)
(overlay/align/offset "right" "top"
(circle 30 "solid" "orchid")
0 10 _)
(overlay/align/offset "left" "bottom"
(circle 30 "solid" "khaki")
10 0 _)
(overlay/align/offset "left" "top"
(circle 30 "solid" "green yellow")
0 0 _))
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[racket-users] Simple loop control
Hi, everyone. I want to write loops simpler. > (do ([i 1 (add1 i)]) ([= i 10]) (display i)) 123456789 > (for-each (lambda (i) (display i)) (range 1 10)) 123456789 In Common Lisp, I like the extended loop like "for" of C-language. [3]> (loop for i from 1 below 10 do (print i)) 1 2 3 4 5 6 7 8 9 NIL Please tell me the best solution. Haruo -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] typed/racket surprises
While experimenting with porting an typed program to Typed Racket, I
encountered a few surprises. Some of these seem like they might be bugs,
others missing features, and several probably are misunderstandings on my
part.
*1. struct subtyping doesn't work with #:type-name*
The following program fails to typecheck with the error "Type Checker:
parent type not a valid structure name: animal":
#lang typed/racket
(struct animal ()
#:type-name Animal
#:transparent)
(struct dog animal ()
#:transparent)
Trying to use `Animal` as the parent of `dog` doesn't work either,
producing the expected error from `struct` that `Animal` is not bound to
struct type information.
*2. Problems with define-struct/exec*
There seem to be some subtleties to using applicable structs created with
define-struct/exec that I do not understand. For example, the following
program fails to typecheck:
#lang typed/racket
(define-struct/exec adder ([name : Symbol])
[(λ (this n) (add1 n)) : (-> adder Number Number)])
(define v
(adder 'v))
(apply v '(41))
with the error "Type Checker: Type of argument to apply is not a function
type:
adder".
I thought that I might need to add a type annotation, but I also am
confused about how to write the type of `v` in the above program. If I
change the above program to one that does typecheck:
#lang typed/racket
(define-struct/exec adder ([name : Symbol])
[(λ (this n) (add1 n)) : (-> adder Number Number)])
(define v
(adder 'v))
(v 41)
the REPL prints the type of v as simply `adder`, but, hovering over the use
of `v` in the last line, the tooltip in DrRacket shows the type as `(U (->
adder Number Number) adder)`.
This seems to be wrong. That function type is the type of the value for
`adder`'s prop:procedure, not the type of an `adder` when used as a
function. Annotating `v` with `(: v (U (-> adder Number Number) adder))`
causes the program to fail to typecheck.
But it isn't clear what type should be used to annotate `v`. Writing `(: v
(U (-> Number Number) adder))` also causes typechecking to fail, as does
experimenting with an intersection type or simply writing `(: v (-> Number
Number))`.
*3. parse-command-line doesn't support usage-help, help-labels, help-proc,
or unknown-proc*
The type for `parse-command-line` doesn't support the `'usage-help`
specification (or `#:usage-help` in an equivalent `command-line` form), so
the following program, which works fine in #lang racket, fails to typecheck:
#lang typed/racket
(parse-command-line
"example"
#("-h")
'([usage-help "here is some usage help"])
void
null)
Worse, the type for the `'help-labels`/`#:help-labels` specification is
wrong, so the following program typechecks successfully but raises a
run-time error:
#lang typed/racket
(parse-command-line
"example"
#("-h")
'([help-labels ("this is a help label")])
void
null)
I have tried to write a better contract for `parse-command-line` using
`require/typed`, but the following program, for example, fails to typecheck
with the error "cannot generate contract for variable arity polymorphic
type":
#lang typed/racket/base
(require/typed
racket/cmdline
[parse-command-line
(All (b a ...)
(-> Path-String
(U (Listof String) (Vectorof String))
(Listof
(U (Pairof 'ps (Listof String))
(Pairof
(U 'final 'help-labels 'multi 'once-any 'once-each)
(Listof (Listof Any)
(-> Any a ... a b)
(Listof String)
b))])
Note that the type above is exactly the type reported by the #lang
typed/racket REPL for `parse-command-line` by default. Also, this type does
not support the optional "help-proc" or "unknown-proc" arguments.
Thanks to all who have worked on and promoted Typed Racket! Really, it is
remarkable how *few* surprises there are when adding types to an untyped
program.
-Philip
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[racket-users] let-syntax example?
Hi Guys, Does anyone have an analogous example for let-syntax to something as simple as this? (let ([a 3]) a) Something like…. (let-syntax ([a 3]) ….) At which point I’m stumped as to what expression in the body would return 3. There are no examples in the Reference. Thanks! Kevin -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] CFP: TFPIE 2018
Dear All, Kindly consider submitting an article/presentation to TFPIE 2018. The call for papers is below. Also, follow us in Facebook: https://www.facebook.com/TFPIE/ Cheers, Marco TFPIE 2018 Call for papers http://www.ccs.neu.edu/home/heather/tfpie2018/ TFPIE 2018 welcomes submissions describing techniques used in the classroom, tools used in and/or developed for the classroom and any creative use of functional programming (FP) to aid education in or outside Computer Science. Topics of interest include, but are not limited to: FP and beginning CS students FP and Computational Thinking FP and Artificial Intelligence FP in Robotics FP and Music Advanced FP for undergraduates FP in graduate education Engaging students in research using FP FP in Programming Languages FP in the high school curriculum FP as a stepping stone to other CS topics FP and Philosophy The pedagogy of teaching FP FP and e-learning: MOOCs, automated assessment etc. Best Lectures – more details below In addition to papers, we are requesting best lecture presentations. What’s your best lecture topic in an FP related course? Do you have a fun way to present FP concepts to novices or perhaps an especially interesting presentation of a difficult topic? In either case, please consider sharing it. Best lecture topics will be selected for presentation based on a short abstract describing the lecture and its interest to TFPIE attendees. Submissions Potential presenters are invited to submit an extended abstract (4-6 pages) or a draft paper (up to 16 pages) in EPTCS style. The authors of accepted presentations will have their preprints and their slides made available on the workshop's website. Papers and abstracts can be submitted via easychair at the following link: https://easychair.org/conferences/?conf=tfpie2018 After the workshop, presenters will be invited to submit (a revised version of) their article for review. The PC will select the best articles for publication in the journal Electronic Proceedings in Theoretical Computer Science (EPTCS). Articles rejected for presentation and extended abstracts will not be formally reviewed by the PC. Dates Submission deadline: May 15th, Anywhere on Earth. Notification: May 21st Workshop: June 14th Submission for formal review: August 17th Notification of full article: October 5th Camera ready: November 2nd Program Committee Kenichi Asai, Ochanomizu University, Japan Kathi Fisler, Brown University, USA Benjamin Lerner, Northeastern University, USA Mark Lewis, Trinity University, USA Heather Miller, Northeastern University, USA & EPFL, Switzerland Elena Machkasova, University of Minnesota, USA David Sands, Chalmers University of Technology, Sweden Emmanuel Schanzer, Bootstrap World, USA -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Racket "google" package
Does anyone actively use the "google" Racket package? ( https://pkgs.racket-lang.org/package/google) There are some things I'm interested in doing, especially with the Google Drive API, but I see that the latest commit to the GitHub repository is from 2016, which seems like a long time ago in Google land. It would be great to hear that someone is using it happily and it still works. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Using Greek Letters
I saw the oficial Racket list of all the LaTeX thing and made some research, but I don't get it. Can someone please explain me how to digite the greek letter Theta for example? And how to use it as the mathematical Theta function if that's possible? Thank you a lot in advance! -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] RacketCon 2018 Website
When looked as a whole, the new racketcon website looks cool. But when you are zoomed in (like I and many other blind/low-vision users frequently are), it looks something like this: Which honestly looks like something is broken with the website. Also, it completely kills screen readers. Here is a capture of what a screen reader thinks that block of text is saying: So, if we are going to keep this logo, could we at least make it an image, or use HTML accessibility tags to say what that block of text should be read as, or something else that doesn't completely kill the website for blind users? ~Leif Andersen -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Installing packages
Yes.
For some package , you can install it for your current user with
the command "raco pkg install " or for the entire installation
(which I often prefer) with "raco pkg install -i ".
So, to install DrRacket, "raco pkg install drracket".
Installing the document you linked to illustrates another point: while you
can mix documentation and implementation in the same package, many
"industrial strength" packages like Scribble split them up into separate
packages, so that in resource-constrained environments you can leave out
the documentation. The document you linked to is part of the "scribble-doc"
package ("raco pkg install scribble-doc"), and the implementation is in
"scribble-lib" ("raco pkg install scribble-lib"). Assuming you want both,
you can just install the main Scribble package ("raco pkg install
scribble"), which pulls both the documentation and the implementation as
dependencies.
I would also note that the minimal installation is very minimal indeed, and
the main distribution is < 600 MB on my machine. Unless you have a
particular reason to want the minimal version, I think the main
distribution is a more friendly place to start.
-Philip
On Mon, Apr 23, 2018 at 9:38 AM, Manuel G <
paracomunicacionesinforma...@gmail.com> wrote:
> Hi,
>
> I'm new to racket, and I'm very interested in DSL , I've installed the
> minimal distribution, and I'd like to
> "install" documentation such as
>
> https://docs.racket-lang.org/scribble/index.html
>
> , is that possible ?
>
> Can I install drracket using raco ?
>
> thanks
> ...
> manolo
>
> --
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[racket-users] Heresy 0.3.0 released
Greetings, Version 0.3.0 of the Heresy programming language has been released, containing a re-implementation of Holes based on Racket boxes, while maintaining the same basic API, plus additional support for a "hole-do" DSL for monadic operations on holes. Special thanks to Greg Hendershott, for both rackjure, which provided some of the internals for the new holes implementation, and for his travis-racket scripts which enabled me to set up CI for Heresy with Travis. You can find Heresy on Github <https://github.com/jarcane/heresy>, or install with raco pkg install heresy. Docs are available at http://docs.racket-lang.org/heresy/index.html* or locally after install. Thanks for your time! Annaia * Note: There seems to be an issue with the package server as it's not rebuilding the hosted docs for me at the moment despite running the recheck twice. I don't know if I'm doing something wrong, someone needs to kick the server, or it's just going to take a moment. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: game help
))) > > > (define createButtonRows (lambda (vContainer rowCount colCount) >; create a rowCount rows of buttons >(cond > ((equal? rowCount 0) ) > (else > (createButRow >(new horizontal-panel% [parent vContainer] > [alignment '(center center)]) > rowCount colCount) > (createButtonRows vContainer (- rowCount 1) > colCount) > ) > ) >) > ) > (define createBoard (lambda (container rowCount colCount) > (createButtonRows >(new vertical-panel% [parent container] > [alignment '(center center)]) >rowCount colCount) > ) > ) > > ; add a message box at the bottom: this will be updated by do show whose > turn it is > (define addMessageArea (lambda (container) > (let ((messageBox (new message% [label ""] > [parent container] [ auto-resize #t]))) >(addUpdator (lambda () > (let ((w (winner))) >(cond > ((equal? w 0) (send > messageBox set-label (format "Player ~a to play" currentPlayer))) > (#t (send messageBox > set-label (format "Winner is ~a" w))) > ) >)) > > > > ;- > ; update a button - change label and disable > > (define updateButton (lambda (but rowNum colNum) >(let* ((val (vector-ref (vector-ref board rowNum) > colNum)) > (str (cond > ((= val 1) "X") > ((= val 2) "O") > (#t "") > ))) > (send but set-label str) > (cond ((> val 0) (send but enable #f))) ; disable > if already played in that cell > ) >) > ) > > ; list of functions to update display > (define updators (list)) > ; run all update functions > (define update (lambda () > (for-each (lambda (func) (func)) updators) > )) > (define addUpdator (lambda (fun) > (set! updators (cons fun updators > ;- > ; initialisation - create the view > (define myFrame (new frame% > [label "O and X game"] > [width 200] [height 200])) > (createBoard myFrame rows cols) > (addMessageArea myFrame) > (send myFrame show #t) > (update) > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Parametric composition?
Your composex macro is very similar to the various forms from the (as far as I can tell) fairly well-known threading package: http://docs.racket-lang.org/threading/index.html Disclaimer: I am the author of the threading package. In any case, there are some differences, but it has the same general feel, and it might suit your needs. Alexis > On May 4, 2018, at 14:57, dexterla...@gmail.com wrote: > > Hi there, > > This is my first post, pardon my ignorance. I have been using a homemade > macro to compose functions together, but still allow semi-currying of > functions (with lambdas) to keep control of the parameters : > > (define-syntax (composex stx) > ; macro to compose functions passing an 'x' parameter > (syntax-case stx () >((_ f1 ...) > (with-syntax ([x-var (datum->syntax stx 'x)]) > #'(compose1 (λ (x-var) f1) ...) > ; unit test > (check-equal? ((composex (string-replace x " " "-") > (string-downcase x) > (string-trim x)) "Hello World") > "hello-world") > > > I often use this or (apply composex (reverse v)) to keep function > applications in order. > > Can you comment on this? Do you think this could be part of the language? > > Cheers, > > Dexter > > P.S. For use in the wild, see provide-generator. Makes generate-provide more > readable : > https://github.com/DexterLagan/provide-generator -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Parametric composition?
Awesome. Your library is far better. Thanks for replying! Dexter On Friday, May 4, 2018 at 4:09:53 PM UTC-4, Alexis King wrote: > Your composex macro is very similar to the various forms from the (as far > as I can tell) fairly well-known threading package: > > http://docs.racket-lang.org/threading/index.html > > Disclaimer: I am the author of the threading package. > > In any case, there are some differences, but it has the same general feel, > and it might suit your needs. > > Alexis > > > On May 4, 2018, at 14:57, dexte...@gmail.com wrote: > > > > Hi there, > > > > This is my first post, pardon my ignorance. I have been using a > homemade macro to compose functions together, but still allow semi-currying > of functions (with lambdas) to keep control of the parameters : > > > > (define-syntax (composex stx) > > ; macro to compose functions passing an 'x' parameter > > (syntax-case stx () > >((_ f1 ...) > > (with-syntax ([x-var (datum->syntax stx 'x)]) > > #'(compose1 (λ (x-var) f1) ...) > > ; unit test > > (check-equal? ((composex (string-replace x " " "-") > > (string-downcase x) > > (string-trim x)) "Hello World") > > "hello-world") > > > > > > I often use this or (apply composex (reverse v)) to keep function > applications in order. > > > > Can you comment on this? Do you think this could be part of the > language? > > > > Cheers, > > > > Dexter > > > > P.S. For use in the wild, see provide-generator. Makes generate-provide > more readable : > > https://github.com/DexterLagan/provide-generator > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Provide form generator
Hi folks, I developed a provide form generator to take the pain out of writing module headers: https://github.com/dexterlagan/provide-generator It works great, but I wonder if there wouldn’t be a simpler and more standard way to write this. My original idea was to parse the module syntax and simply delete the body of each define form, converting each function definition to string and use it as comment to each provide element. I couldn’t make it work that way, so I had to switch from syntax objects to strings half-way and handle it by hand. Any insight? Thanks! Dex -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] DrRacket Plugin development
Hi all! I'm an undergraduate TA for a Canadian university which uses DrRacket as its primary IDE for its introductory programming course. As a fun side project to keep me busy during the summer, I was hoping to develop a DrRacket plugin which basically acts as an in-editor help desk. My vision for this is to have a window that pops up once a user hovers over a function name that contains information from the help desk. I've already looked at the existing documentation for creating plugins, but it seems pretty esoteric. I was wondering if anyone has had any experience developing tools like this. Thanks! -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Student code metrics
Hi! I was about to start building a tool for statically analyzing student code. But I first want to ask if there's related work out there. I'm interested in relatively simple stuff -- e.g. How many functions did the student write? How many expressions? What's the average nesting depth of expressions? Etc. Basically, I want to start quantifying things about students' coding styles -- both to identify potential problems and also to help students set goals (e.g. "Today, you wrote 2 functions. Tomorrow, I want you to try to write 3!"). Before I start writing this myself, is there anything that I should know about? Has someone already done exactly this? Or is there some library for static analysis or code metrics that I should be building upon? I searched a bit and couldn't find a lot. Maybe I'm using the wrong keywords. --Stephen -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Edmond's Blossom Algorithm
Context: I have students A, B, C, ..., Z that needs to work in pairs for their exam. Each student has made a wish list with 3 other students that they'd like to work with. I need to find the maximum possible pairing. I think - maybe - that the algorithm I need is Edmond's blossom algorithm. Am I so lucky that someone has this in Racket? https://en.wikipedia.org/wiki/Blossom_algorithm http://www.cs.dartmouth.edu/~ac/Teach/CS105-Winter05/Handouts/tarjan-blossom.pdf /Jens Axel -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] handin-server submissions
Hi, everyone I'm currently in charge of a handin-server instance for a course at my university. We're currently experiencing issues where students are unable to handin their work, receiving this error message: login error: user (STUDENT_USERNAME) not in assignment/section lab-01 I think I've configured config.rktd correctly, with "lab-01" being in the correct active-dirs s-expression. Does anyone have an idea of what's going on? I'd be happy to share my config.rktd file. Thanks! James -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
Interestingly, it looks like this change is a deliberate one, made by Ryan Culpepper back in 2011. Here’s the relevant commit: commit 738bf41d106f4ecd9111bbefabfd78bec8dc2202 Author: Ryan Culpepper Date: Tue Nov 22 02:46:32 2011 -0700 bypass ssax/ssax module trim exports from main (breaks backwards compat!) diff --git a/main.rkt b/main.rkt index bf3530d..89f27d3 100644 --- a/main.rkt +++ b/main.rkt @@ -27,5 +27,11 @@ (provide (all-from-out "modif.rkt")) (provide (all-from-out "serializer.rkt")) -(require "ssax/ssax.rkt") -(provide (all-from-out "ssax/ssax.rkt")) +(require "ssax/multi-parser.rkt" + "ssax/sxpathlib.rkt" + "ssax/SXML-tree-trans.rkt" + "ssax/SSAX-code.rkt") +(provide ssax:multi-parser + (all-from-out "ssax/sxpathlib.rkt") + pre-post-order + ssax:xml->sxml) Ryan, do you know why you put ssax:multi-parser in, but not ssax:make-parser? Cheers! John > On May 15, 2018, at 6:42 AM, N. Raghavendra wrote: > > I was trying out Oleg Kiselyov's example > > http://okmij.org/ftp/Scheme/remove-markup.scm > > which illustrates the use of `ssax:make-parser'. I have a couple of > questions: > > 1. To call ssax-make-parser, I had to require both sxml and > sxml/ssax/ssax. Is that the correct way of doing it? > > 2. It seems an important function, and I was wondering why the sxml > module does not provide it, the way it does ssax:xml->sxml, so that one > doesn't need to further require sxml/ssax/ssax. I see that sxml > provides ssax:multi-parser. Is it similar to ssax:make-parser? > > Thanks, > Raghu. > > -- > N. Raghavendra , http://www.retrotexts.net/ > Harish-Chandra Research Institute, http://www.hri.res.in/ > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
At 2018-05-15T17:36:44-04:00, John Clements wrote: > Interestingly, it looks like this change is a deliberate one, made by > Ryan Culpepper back in 2011. Here’s the relevant commit: Thanks for tracing that change. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[racket-users] Re: Unicode identifiers
Where you found (string→symbol? Grakcet version you have? Welcome to DrRacket, version 6.11 [3m]. Language: racket, with debugging; memory limit: 128 MB. > (string→symbol "map") . . string→symbol: undefined; cannot reference an identifier before its definition > miercuri, 16 mai 2018, 07:15:43 UTC+3, N. Raghavendra a scris: > > I just found that > > > (define φoo→β=αρ "Foo→b=ar") > > φoo→β=αρ > "Foo→b=ar" > >(call-with-output-file "/tmp/foo.txt" >(λ (out) >(display (xml-remove-markup) out)) >#:exists 'replace) > > etc., work. That's nice. > > In general, is it possible to declare, e.g., '→' as equivalent to '->' > in identifiers? Then, I can use > > > (string→symbol "map") > > instead of > > > (string->symbol "map") > > Thanks, > Raghu. > > -- > N. Raghavendra >, http://www.retrotexts.net/ > > Harish-Chandra <http://www.retrotexts.net/Harish-Chandra> Research > Institute, http://www.hri.res.in/ > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
On 05/15/2018 11:36 PM, John Clements wrote: Interestingly, it looks like this change is a deliberate one, made by Ryan Culpepper back in 2011. Here’s the relevant commit: commit 738bf41d106f4ecd9111bbefabfd78bec8dc2202 Author: Ryan Culpepper Date: Tue Nov 22 02:46:32 2011 -0700 bypass ssax/ssax module trim exports from main (breaks backwards compat!) diff --git a/main.rkt b/main.rkt index bf3530d..89f27d3 100644 --- a/main.rkt +++ b/main.rkt @@ -27,5 +27,11 @@ (provide (all-from-out "modif.rkt")) (provide (all-from-out "serializer.rkt")) -(require "ssax/ssax.rkt") -(provide (all-from-out "ssax/ssax.rkt")) +(require "ssax/multi-parser.rkt" + "ssax/sxpathlib.rkt" + "ssax/SXML-tree-trans.rkt" + "ssax/SSAX-code.rkt") +(provide ssax:multi-parser + (all-from-out "ssax/sxpathlib.rkt") + pre-post-order + ssax:xml->sxml) Ryan, do you know why you put ssax:multi-parser in, but not ssax:make-parser? Sorry, I don't remember. My guess is that either leaving it out was just an oversight, or that I thought it was only an internal helper function for something else. Ryan Cheers! John On May 15, 2018, at 6:42 AM, N. Raghavendra wrote: I was trying out Oleg Kiselyov's example http://okmij.org/ftp/Scheme/remove-markup.scm which illustrates the use of `ssax:make-parser'. I have a couple of questions: 1. To call ssax-make-parser, I had to require both sxml and sxml/ssax/ssax. Is that the correct way of doing it? 2. It seems an important function, and I was wondering why the sxml module does not provide it, the way it does ssax:xml->sxml, so that one doesn't need to further require sxml/ssax/ssax. I see that sxml provides ssax:multi-parser. Is it similar to ssax:make-parser? Thanks, Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
Alternative 1: Use filtered-in to require renamed versions. (filtered-in <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Frequire..rkt%29._filtered-in%29%29> proc-expr require-spec) Applies an arbitrary transformation on the import names (as strings) of require-spec. The proc-expr must evaluate at expansion time to a single-argument procedure, which is applied on each of the names from require-spec. For each name, the procedure must return either a string for the import’s new name or #f to exclude the import. For example, (require <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29> (filtered-in <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Frequire..rkt%29._filtered-in%29%29> (lambda <http://docs.racket-lang.org/reference/lambda.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29> (name) (and <http://docs.racket-lang.org/reference/if.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._and%29%29> (regexp-match? <http://docs.racket-lang.org/reference/regexp.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._regexp-match~3f%29%29> #rx"^[a-z-]+$" name) (regexp-replace <http://docs.racket-lang.org/reference/regexp.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._regexp-replace%29%29> #rx"-" (string-titlecase <http://docs.racket-lang.org/reference/strings.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._string-titlecase%29%29> name) ""))) racket/base)) imports only bindings from racket/base <http://docs.racket-lang.org/reference/index.html?q=regexp-in> that match the pattern #rx"^[a-z-]+$", and it converts the names to “camel case.” Alternative 2: Define your own version of #%top that replaces identifiers with unicode -> to standard ->. Alternative 1 is best. /Jens Axel 2018-05-16 6:15 GMT+02:00 N. Raghavendra : > I just found that > > > (define φoo→β=αρ "Foo→b=ar") > > φoo→β=αρ > "Foo→b=ar" > >(call-with-output-file "/tmp/foo.txt" >(λ (out) >(display (xml-remove-markup) out)) >#:exists 'replace) > > etc., work. That's nice. > > In general, is it possible to declare, e.g., '→' as equivalent to '->' > in identifiers? Then, I can use > > > (string→symbol "map") > > instead of > > > (string->symbol "map") > > Thanks, > Raghu. > > -- > N. Raghavendra , http://www.retrotexts.net/ > Harish-Chandra Research Institute, http://www.hri.res.in/ > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- -- Jens Axel Søgaard -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
> On May 16, 2018, at 6:37 AM, Jens Axel Søgaard wrote: > > Alternative 1: Use filtered-in to require renamed versions. > > ( <>filtered-in > <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Frequire..rkt%29._filtered-in%29%29> > proc-expr require-spec) > Applies an arbitrary transformation on the import names (as strings) of > require-spec. The proc-expr must evaluate at expansion time to a > single-argument procedure, which is applied on each of the names from > require-spec. For each name, the procedure must return either a string for > the import’s new name or #f to exclude the import. > > > For example, > (require > <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29> > (filtered-in > <http://docs.racket-lang.org/reference/require.html?q=regexp-in#%28form._%28%28lib._racket%2Frequire..rkt%29._filtered-in%29%29> > (lambda > <http://docs.racket-lang.org/reference/lambda.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29> > (name) > (and > <http://docs.racket-lang.org/reference/if.html?q=regexp-in#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._and%29%29> > (regexp-match? > <http://docs.racket-lang.org/reference/regexp.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._regexp-match~3f%29%29> > #rx"^[a-z-]+$" name) > (regexp-replace > <http://docs.racket-lang.org/reference/regexp.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._regexp-replace%29%29> > #rx"-" (string-titlecase > <http://docs.racket-lang.org/reference/strings.html?q=regexp-in#%28def._%28%28quote._~23~25kernel%29._string-titlecase%29%29> > name) ""))) > racket/base)) > imports only bindings from racket/base > <http://docs.racket-lang.org/reference/index.html?q=regexp-in> that match the > pattern #rx"^[a-z-]+$", and it converts the names to “camel case.” > Alternative 1 is best. > > /Jens Axel Here is a `transform-right-arrow-in` definition that transforms -> into →: #lang racket (require racket/require racket/require-syntax (for-syntax syntax/parse)) (begin-for-syntax ;; String -> String (define (transform-right-arrow name) (regexp-replace* #rx"->" name "→"))) (define-require-syntax transform-right-arrow-in (syntax-parser [(transform-right-arrow-in require-spec) #'(filtered-in transform-right-arrow require-spec)])) ;; Using it: (require (transform-right-arrow-in racket/base)) (symbol→string 'blubber) (string→number "987") (real→double-flonum 377) (list→vector (list 144 233 377 610 987 1597)) -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
On Wed, May 16, 2018 at 6:37 AM, Jens Axel Søgaard wrote: > and it converts the names to “camel case.” > Why do you hurt me, Jens? You always seemed like such a nice person. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
At 2018-05-16T12:37:47+02:00, Jens Axel Søgaard wrote: > (require (filtered-in > (lambda (name) > (and (regexp-match? #rx"^[a-z-]+$" name) > (regexp-replace #rx"-" (string-titlecase name) > ""))) > racket/base)) Thank you for the reply. I tried this at the REPL, and got an error: racket@> (require (filtered-in (λ (name) (string-replace name "->" "→")) racket)) stdin::4186: filtered-in: not a require sub-form ... racket@> (require racket/require) racket@> (require (filtered-in (λ (name) (string-replace name "->" "→")) racket)) string-replace: undefined; cannot reference undefined identifier ... racket@> (require racket/string) racket@> (require (filtered-in (λ (name) (string-replace name "->" "→")) racket)) string-replace: undefined; cannot reference undefined identifier ... Wonder what I am doing wrongly. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
At 2018-05-16T09:12:18-04:00, Alex Knauth wrote: > Here is a `transform-right-arrow-in` definition that transforms -> > into →: > > #lang racket > (require racket/require > racket/require-syntax > (for-syntax syntax/parse)) > > (begin-for-syntax > ;; String -> String > (define (transform-right-arrow name) > (regexp-replace* #rx"->" name "→"))) > > (define-require-syntax transform-right-arrow-in > (syntax-parser > [(transform-right-arrow-in require-spec) > #'(filtered-in transform-right-arrow require-spec)])) > > ;; Using it: > > (require (transform-right-arrow-in racket/base)) > > (symbol→string 'blubber) Thanks, this works. However, at this stage of my experience with Racket, the direct `filtered-in' method suggested by Jens appears simpler and easier. As I said in an earlier message, I seem to be using it wrongly. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
`racket/string` needs to be required _for syntax_ in order to work in the suggested way (because it's bindings are needed at compile time). The following works for me in a module: ``` #lang racket/base (require (for-syntax racket/base racket/string) racket/require) (require (filtered-in (λ (name) (string-replace name "->" "→")) racket)) (string→number "42") ``` -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
Would it be possible to adjust the readtable to replace "→" with "->" ? On Wednesday, May 16, 2018 at 10:32:43 AM UTC-4, Andrew Kent wrote: > > `racket/string` needs to be required _for syntax_ in order to work in the > suggested way (because it's bindings are needed at compile time). > > The following works for me in a module: > > ``` > #lang racket/base > > (require (for-syntax racket/base racket/string) > racket/require) > > (require (filtered-in > (λ (name) > (string-replace name "->" "→")) > racket)) > > (string→number "42") > ``` > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
It seems like make-parser should probably be provide’d. I’ve pushed a change to make ssax:make-parser a top-level provide. Would you (N. Raghavendra) be interested in taking the raw pseudo-documentation currently provided for ssax:make-parser and reformatting it into something useful, perhaps with an example? John Clements > On May 16, 2018, at 3:11 AM, Ryan Culpepper wrote: > > On 05/15/2018 11:36 PM, John Clements wrote: >> Interestingly, it looks like this change is a deliberate one, made by Ryan >> Culpepper back in 2011. Here’s the relevant commit: >> commit 738bf41d106f4ecd9111bbefabfd78bec8dc2202 >> Author: Ryan Culpepper >> Date: Tue Nov 22 02:46:32 2011 -0700 >> bypass ssax/ssax module >> trim exports from main (breaks backwards compat!) >> diff --git a/main.rkt b/main.rkt >> index bf3530d..89f27d3 100644 >> --- a/main.rkt >> +++ b/main.rkt >> @@ -27,5 +27,11 @@ >> (provide (all-from-out "modif.rkt")) >> (provide (all-from-out "serializer.rkt")) >> -(require "ssax/ssax.rkt") >> -(provide (all-from-out "ssax/ssax.rkt")) >> +(require "ssax/multi-parser.rkt" >> + "ssax/sxpathlib.rkt" >> + "ssax/SXML-tree-trans.rkt" >> + "ssax/SSAX-code.rkt") >> +(provide ssax:multi-parser >> + (all-from-out "ssax/sxpathlib.rkt") >> + pre-post-order >> + ssax:xml->sxml) >> Ryan, do you know why you put ssax:multi-parser in, but not ssax:make-parser? > > Sorry, I don't remember. My guess is that either leaving it out was just an > oversight, or that I thought it was only an internal helper function for > something else. > > Ryan > > >> Cheers! >> John >>> On May 15, 2018, at 6:42 AM, N. Raghavendra wrote: >>> >>> I was trying out Oleg Kiselyov's example >>> >>> http://okmij.org/ftp/Scheme/remove-markup.scm >>> >>> which illustrates the use of `ssax:make-parser'. I have a couple of >>> questions: >>> >>> 1. To call ssax-make-parser, I had to require both sxml and >>> sxml/ssax/ssax. Is that the correct way of doing it? >>> >>> 2. It seems an important function, and I was wondering why the sxml >>> module does not provide it, the way it does ssax:xml->sxml, so that one >>> doesn't need to further require sxml/ssax/ssax. I see that sxml >>> provides ssax:multi-parser. Is it similar to ssax:make-parser? >>> >>> Thanks, >>> Raghu. >>> >>> -- >>> N. Raghavendra , http://www.retrotexts.net/ >>> Harish-Chandra Research Institute, http://www.hri.res.in/ >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Racket Users" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to racket-users+unsubscr...@googlegroups.com. >>> For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
At 2018-05-16T13:49:52-04:00, John Clements wrote: > It seems like make-parser should probably be provide’d. I’ve pushed a > change to make ssax:make-parser a top-level provide. Thank you very much. In fact, it may be a good idea to restore (provide (all-from-out "ssax/ssax.rkt")) > Would you (N. Raghavendra) be interested in taking the raw > pseudo-documentation currently provided for ssax:make-parser and > reformatting it into something useful, perhaps with an example? Would > you (N. Raghavendra) be interested in taking the raw > pseudo-documentation currently provided for ssax:make-parser and > reformatting it into something useful, perhaps with an example? I'll draft something, and submit a PR to jbclements/sxml on GitHub. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
At 2018-05-16T07:32:43-07:00, Andrew Kent wrote: > #lang racket/base > > (require (for-syntax racket/base racket/string) > racket/require) > > (require (filtered-in > (λ (name) > (string-replace name "->" "→")) > racket)) > > (string→number "42") Thank you. I now have the following in my file: -- #lang racket/base (module syntax-transform racket/base (require racket/string) (provide arrow-beautify) (define (arrow-beautify string) (string-replace string "->" "→"))) (require racket/require (for-syntax 'syntax-transform)) (require (filtered-in arrow-beautify racket)) -- Running this file in Dr Racket, I get > (string→symbol "map") 'map I get the same in Emacs/Geiser with `geiser-mode-switch-to-repl-and-enter' (C-c C-a). Thanks to everyone who replied! Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
> On May 16, 2018, at 11:17 AM, N. Raghavendra wrote: > > At 2018-05-16T13:49:52-04:00, John Clements wrote: > >> It seems like make-parser should probably be provide’d. I’ve pushed a >> change to make ssax:make-parser a top-level provide. > > Thank you very much. In fact, it may be a good idea to restore > > (provide (all-from-out "ssax/ssax.rkt”)) Maybe… I’m inclined to respect Ryan’s thinking on this; there are a bunch of functions in there that look like they definitely shouldn’t be exposed, and couldn’t reasonably be called from outside. In a quick scan of the existing quasi-documentation for ssax.rkt, make-parser was the only one that looked to me like it might productively be used from outside. John > >> Would you (N. Raghavendra) be interested in taking the raw >> pseudo-documentation currently provided for ssax:make-parser and >> reformatting it into something useful, perhaps with an example? Would >> you (N. Raghavendra) be interested in taking the raw >> pseudo-documentation currently provided for ssax:make-parser and >> reformatting it into something useful, perhaps with an example? > > I'll draft something, and submit a PR to jbclements/sxml on GitHub. > > Raghu. > > -- > N. Raghavendra , http://www.retrotexts.net/ > Harish-Chandra Research Institute, http://www.hri.res.in/ > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
At 2018-05-16T14:56:00-04:00, John Clements wrote: > Maybe… I’m inclined to respect Ryan’s thinking on this; there are a > bunch of functions in there that look like they definitely shouldn’t > be exposed, and couldn’t reasonably be called from outside. In a quick > scan of the existing quasi-documentation for ssax.rkt, make-parser was > the only one that looked to me like it might productively be used from > outside. Sure, I guess that's for the best. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
John Clements, et al., thank you for ongoing work on packaging Oleg Kiselyov's SXML-related libraries nicely for Racket. It's not an easy task. (Background, for the list... Years ago, one of the great masters of Scheme, Oleg Kiselyov, did a lot of excellent work on XML in Scheme, released the code as open source, and wrote articles about some of it. Unfortunately, the modern Racket module system, package system, and API documentation conventions weren't available to him at the time. Packaging this wealth of Oleg's code after the fact, as if it were developed with the benefit of those structures, requires some archaeological work and judgment calls, and I really appreciate that John tackled this. Also deserving mention: Kirill Lisovsky and I think Dmity Lizorkin did a lot of earlier work to port/package Oleg's libraries for multiple Scheme dialects, including for an early version of Racket nee PLT Scheme, which got us by for years.) -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] ssax:make-parser
At 2018-05-16T14:56:00-04:00, John Clements wrote: > In a quick scan of the existing quasi-documentation for ssax.rkt, > make-parser was the only one that looked to me like it might > productively be used from outside. `ssax:read-pi-body-as-string' is another identifier from sxml/ssax/ssax, which I am finding useful. Here is a usage adapted from https://github.com/bernied/ssax/blob/master/SSAX/examples/ssax-extraction.scm (define (outline-pi port pi-tag seed) ;; Read the body of PI and ignore it. (let ((dummy (ssax:read-pi-body-as-string port))) seed)) This procedure can then be specified as a handler for processing instructions (PIs) in the document, which just ignores them. Without such a dummy handler, one gets a warning message from ssax:make-parser that PIs are being left unprocessed. However, I am not advocating a full export of ssax from sxml. I am fine with importing ssax separately in my files. I just thought that it is good to keep a record of its useful identifiers. Raghu. -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
One of my favorite small things about Racket is that is permits almost anything to be an identifier -- allowing you to use whatever natural names you prefer. In addition to Unicode, identifiers can start with a number: (define 100-continue? "✓") In the rare case where an identifier wouldn't be valid, you can use it anyway inside pipe chars: (define |identifier with spaces| "✓") (But it would be idiomatic to use `identifier-without-spaces`.) You can even use identifiers that are entirely some number of spaces: (define | | "one space") (define | | "two spaces") (equal? | | | |) ;#f Which I suppose can be a nutritious part of a code obfuscation diet. :) One gotcha, which I remember confusing myself with, early on: (define 'foo "foo") '1 ;"foo" '2 ;"foo" Huh? That's because 'foo is reader shorthand for (quote foo). So the above is actually: (define (quote foo) "foo") (quote 1) (quote 2) In other words, it defines `quote` as a constant function that always returns "foo". Definitions in a module shadow those provided by the module's language -- in this case the `quote` provided by racket. (Definitions provided by a `require`d module, however, can't be shadowed -- that's a redefinition error.) -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [racket-users] Unicode identifiers
At 2018-05-17T11:11:26-04:00, Greg Hendershott wrote: > One gotcha, which I remember confusing myself with, early on: > > (define 'foo "foo") > '1 ;"foo" > '2 ;"foo" > > Huh? That's because 'foo is reader shorthand for (quote foo). So the > above is actually: > > (define (quote foo) > "foo") > (quote 1) > (quote 2) Yes, that'd be certainly confusing if one types (define 'foo "foo") instead of (define foo "foo") by mistake. Thanks for all the interesting information. Raghu. PS: Just migrated to racket-mode from geiser, so will ask here if I have any queries there. Thanks for the mode too! -- N. Raghavendra , http://www.retrotexts.net/ Harish-Chandra Research Institute, http://www.hri.res.in/ -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
