Re: [racket-users] Multipart HTTP requests

On 1/29/2019 8:11 AM, Matthew Flatt wrote: At Tue, 29 Jan 2019 04:17:53 -0500, Christopher Lemmer Webber wrote: > Any thoughts on how I should move forward? Has anyone else written a > multipart library I don't know about, for instance? Is that the same as MIME's multipart as used in email?

Re: [racket-users] Github collection for making a language

On 1/24/2019 3:39 PM, Stephen De Gabrielle wrote:  (does windows include `make` ?) No.  Windows provides no development tools aside from scripting [cmd or powershell]. Couple alternatives [there may be more]:  Cygwin provides a Unix/Linux like environment [bash, utilities] for Windows

Re: [racket-users] snake game

On 1/24/2019 12:56 PM, orenpa11 wrote: I need to create a project in pertty big . why this code is not been supported ? "Pretty Big" is supported.   - go to the Language menu   - select "Choose Language"   - go down to "Other Languages" If you don't see a list under "Other Languages", click

Re: [racket-users] Re: Execution ends before log message is displayed

On 1/23/2019 12:02 PM, Brian Adkins wrote: It looks like you're still using an arbitrary wait time to assume the logging event queue is empty. I like it much better than my sleep idea, but it seems like there is still the problem of choosing between 1) using a timeout value to short and

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/22/2019 6:25 PM, Zelphir Kaltstahl wrote: >> I disagree on one more point. It is not necessary to always remember >> the low level character of code running on a machine, if the language >> we are using abstracts it well and guarantees us, that there will not >> be strange effects in all

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/22/2019 2:31 PM, Zelphir Kaltstahl wrote: If the terms procedures and functions in computing have no significant difference, then why use two terms for the same thing, of which one is already used in mathematics, enabling confusion to appear? This would make a fine argument for not

Re: [racket-users] Distributed places question

On 1/22/2019 10:36 AM, Matt Jadud wrote: My initial wild guess is that the problem is in the queen.  Going by the description it's way overly complicated, with plenty of opportunities for something to get lost. Perhaps. It's not a long driver, as code goes. Length really

Re: [racket-users] Distributed places question

On 1/21/2019 8:56 PM, Matt Jadud wrote: Hi all, I have too much code for a "minimal working example." Every time I run a distributed places program, I get different results. Sadly, it's complex, and I'm confident there are multiple places I could be missing something. This is all running

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/21/2019 11:52 PM, Anthony Carrico wrote: On 1/18/19 6:36 PM, George Neuner wrote: > Historically, many computer language designers were mathematicians, and > they deliberately sought to distinguish "computer" functions from > "mathematical" functions. >

Re: [racket-users] Re: Execution ends before log message is displayed

On 1/20/2019 6:34 PM, Brian Adkins wrote: Thanks. I do use dynamic-wind in various ways now, but I'm not sure how it would help me in this particular scenario. My log receiver thread is simply in a loop sync'ing on the logger, so I can't wait for my thread. I don't know how to determine

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

And one by our own Jay McCarthy (with Neil Toronto) https://www.computer.org/cms/Computer.org/ComputingNow/issues/2014/10/mcs2014040080.pdf -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/19/2019 10:37 PM, David Storrs wrote: On Fri, Jan 18, 2019, 6:36 PM George Neuner <mailto:gneun...@comcast.net> wrote:  witness the legions of newbies every year who don't understand that computer arithmetic differs from the math they were taught in school. Does i

[racket-users] Re: Execution ends before log message is displayed

On Thu, 17 Jan 2019 18:08:00 -0800 (PST), Brian Adkins wrote: >Aha! Thanks for the quick reply. I'll have to rethink how I'm handling >logging. One thing you might try is to use dynamic-wind in your main thread, so you can cleanly end loggin and shut down your logging thread even if the main

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/17/2019 11:41 AM, Anthony Carrico wrote: Weird! A procedure is a (branching) sequence of instructions. Non-programmers have an accurate notion of the word from outside of computer programming in recipes and instruction manuals. A function maps inputs to outputs. Non-programmers often

Re: [racket-users] My gmail auto receives new top-level entries from [Racket Users] but not reply entries...

On 1/15/2019 11:12 PM, Pierpaolo Bernardi wrote - Go to https://groups.google.com/forum/#!forum/racket-users - Click the button with no text on the right which shows "My settings" if you mouse over it. - Choose "Membership and email settings" Tune the settings according to your preferences.

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/14/2019 9:56 AM, Laurent wrote: I'm not entirely sure where I got that from, but to me a procedure is a ("impure") function with possible side effects (printing, mutating a global variable, sending emails, etc.). By contrast, in any given context, a function is (again, to me) synonymous

[racket-users] Re: Help narrow down problem using plt-web-server:

On Sun, 13 Jan 2019 05:51:51 -0500, Neil Van Dyke wrote: >[3] But trivia can pay off.  Without spoilers, if anyone has not seen >the film "My Cousin Vinny", I recommend watching it in its entirety. Was your Pontiac Tempest metallic mint green? -- You received this message because you are

Re: [racket-users] Are the terms "function" and "procedure" synonymous in Racket?

On 1/13/2019 1:49 PM, Alexis King wrote: Disclaimer: this answer is extremely non-authoritative. Ditto. I think that, in Racket, the terms are used more or less interchangeably. The technical term is “procedure”, but as you point out, the term “function” is also used to mean the same

Re: [racket-users] Help narrow down problem using plt-web-server:

On 1/10/2019 3:50 PM, Don Green wrote: I suspect that I: (a) may be misusing plt-web-server; or (b) have not actually installed my server-cert.pem properly even though the verification operation indicates a successful installation: openssl verify -CApath /etc/ssl/certs server-cert.pem returns:

Re: [racket-users] How to build unix paths on windows with build-path/convention-type

On 1/10/2019 9:14 AM, David K. Storrs wrote: On Tuesday, May 22, 2018 at 7:56:21 AM UTC-4, Matthew Flatt wrote: To build paths for a convention other than the current machine's convention, you have to work in bytes instead of strings.   (define (bs->p bs) (bytes->path bs 'unix))

[racket-users] Re: Functional augmenting

Hi Neil, On Tue, 8 Jan 2019 14:28:29 -0500, Neil Van Dyke wrote: >In current Racket, the defining module wasn't expecting its own >procedure definition to change out from under it, and other users of >that module also weren't expecting it to change. > >Racket semantics for procedures seems

Re: [racket-users] Re: Functional augmenting

Hi Neil, On 1/7/2019 9:58 PM, Neil Van Dyke wrote: George Neuner wrote on 1/7/19 4:49 PM: Though I mostly agree with you, your "advice" does have its uses: http://www.gigamonkeys.com/book/object-reorientation-generic-functions.html     in particular see the sections on method co

Re: [racket-users] Re: Functional augmenting

On 1/7/2019 5:32 PM, David Thrane Christiansen wrote: > The basic generics machinery isn't terribly hard to implement inside a > compiler. I'm not sure though how I would do it on top of Racket. I'm > sure I could hack up some ugly macros that would work, but it seems like > it needs to be

Re: [racket-users] Re: Functional augmenting

On 1/7/2019 2:23 PM, Neil Van Dyke wrote: George Neuner wrote on 1/7/19 1:12 PM: Your examples look a lot like what is possible using Lisp's generic functions: specifically "before", "after" and "around" functions. Before/after/around are what I call "ad

Re: [racket-users] Re: Functional augmenting

Hi David, On 1/7/2019 12:57 PM, David Storrs wrote: I haven't worked with Racket's generics before, but a quick skim through the documentation suggests that no, that's not it.  Racket generics appear to relate to collections and structs, whereas I was looking for something that operates on

[racket-users] Re: Functional augmenting

On Fri, 4 Jan 2019 13:30:43 -0500, David Storrs wrote: >Racket's OO system has the 'augment' family of functionality that allows >you to change how a function works. I'm wondering if there's a way to do >something similar in functional Racket. For example, when I was working in >Perl I used to

[racket-users] Re: hackernews

On Thu, 27 Dec 2018 17:15:39 -0500, Hendrik Boom wrote: >On Thu, Dec 27, 2018 at 02:06:22PM -0800, Andrew Gwozdziewycz wrote: >> On Thu, Dec 27, 2018 at 8:24 AM Brett Gilio wrote: >> >> Python was meant to be a better version >> of that. The History of Python wiki page suggests it was meant as

[racket-users] Re: hackernews

On Thu, 27 Dec 2018 21:27:02 -0500, Neil Van Dyke wrote: >Stephen De Gabrielle wrote on 12/27/18 4:47 PM: >> I always wanted to ask if the prototype object model is a good >> idea or bad idea? > >I think it's not a bad idea, but I think you probably wouldn't use it >for general-purpose OOA,

[racket-users] off-topic: SQLite

This hit the news yesterday:  SQLite contained a remote code execution bug.  According to the ZDNet article the bug has been fixed as  of  v3.26.0 released December 1st.  If your application uses SQLite, you probably should update it.   Hopefully the Racket maintainers will update the

[racket-users] Re: JSON vs. normal Racket for simple serialization to database

On Wed, 12 Dec 2018 07:26:44 -0800 (PST), Brian Adkins wrote: >I have some simple serialization needs. In Ruby, I would always serialize >an object to JSON and store in a postgres text column. However, w/ Racket, >it appears another option is to simply use read/write. Any reason not to >use

Re: [racket-users] GUI in Racket

On 12/9/2018 7:40 AM, Hendrik Boom wrote: On Thu, Oct 11, 2018 at 09:06:57PM -0400, George Neuner wrote: > > Closing the main window normally causes the program to exit ... likely the > source of your problem. Is this specific to Windows? X on Linux allows one to write

Re: [racket-users] Possible Typed Racket bugs (regarding, separately, for/fold and occurrence typing)

ote]. My (maybe flawed) understanding is that internal define and let both create just a local and not a named binding. George > On Dec 1, 2018, at 10:40, George Neuner wrote: > > > > On 12/1/2018 12:28 PM, hashim muqtadir wrote: >> But this doesn't typecheck:

[racket-users] Re: What is the best way to daemonize a Racket program on linux?

On Thu, 29 Nov 2018 07:19:17 -0800 (PST), Brian Adkins wrote: >Just out of curiosity, why do you feel using daemon(3) is not a great idea? >I'm not disagreeing, just curious about your reasons. > >On Thursday, November 29, 2018 at 5:54:42 AM UTC-5, Tony Garnock-Jones >wrote: >> >> IMO using

Re: [racket-users] Possible Typed Racket bugs (regarding, separately, for/fold and occurrence typing)

On 12/1/2018 12:28 PM, hashim muqtadir wrote: But this doesn't typecheck: > (for ([x (in-list '("123" "432" "234"))])     (define num (string->number x))     (unless num   (error "Not a number"))     (define double (* num 2))     (display (format "~s" double))) . Type Checker: type

Re: [racket-users] cons-specific optimizations?

On 11/28/2018 12:15 PM, Alexis King wrote: > On Nov 28, 2018, at 07:15, Matthew Flatt wrote: > > Yes, that's special handling for pairs in the sense that the > traditional Racket implementation takes advantage of leftover bits in a > pair object, and it uses two of them for "is a list" and

Re: [racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

On 11/26/2018 4:44 PM, Neil Van Dyke wrote: I don't know how Snobol dropped out of awareness.  I almost never heard of it in the MS-DOS, Windows, or Unix workstation circles, even before Perl, though occasionally you'd see an interpreter on a BBS or freeware/shareware list. That's funny

Re: [racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

Very nice recap.  +1. On 11/26/2018 1:50 PM, Neil Van Dyke wrote: * the alternative to Perl was usually C or early C++ (though extension languages like Tcl and Python were starting to kick around; but Tcl's main use was relatively easy GUI development, and Python was just a bare language

Re: [racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

On 11/26/2018 11:40 AM, David Storrs wrote: On Sun, Nov 25, 2018 at 4:16 AM George Neuner <mailto:gneun...@comcast.net>> wrote: On 11/25/2018 4:11 AM, Bogdan Popa wrote: Is there a way to fork(2) in Racket? Unfortunately, no.  Racket is cross-platform, and Window

Re: [racket-users] Multiple places listening to a TCP port [was: Racket application servers]

On 11/25/2018 6:13 PM, Matthew Flatt wrote: An alternative to exposing `SO_REUSEPORT` would be to allow TCP listeners to be sent across place channels, so multiple places in same Racket process could accept connections from the same listener. That would only work for place-based parallelism,

Re: [racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

On 11/25/2018 4:11 AM, Bogdan Popa wrote: One way you might also solve this on UNIX systems is you could fork after listening on the socket. The file descriptor for the socket from the parent would then be shared with the children and so their accept calls would be "load balanced" by way of

[racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

Paulo Matos recently announced a library called "Loci" that allows for using mulitple processes with much the same API as places. https://pkgs.racket-lang.org/package/loci I haven't tried it, but it looks interesting. George -- You received this message because you are subscribed to the

[racket-users] Re: Multiple places listening to a TCP port [was: Racket application servers]

On 11/24/2018 7:39 PM, Philip McGrath wrote: On Fri, Nov 23, 2018 at 5:44 PM George Neuner <mailto:gneun...@comcast.net>> wrote: Multiple (identical) server instances running on the same machine can listen for connections on the same network port - an incoming cl

Re: [racket-users] Racket application servers

On 11/23/2018 4:38 PM, Philip McGrath wrote: I'm not familiar with Ruby, so this is just some general information. The Racket web server already supports concurrency with its built-in green threads, so handling one request won't block the concurrent handling of another. (Not all languages'

Re: [racket-users] software engineering (Was: Does Racket support tail call elimination?)

On 11/12/2018 7:08 PM, Neil Van Dyke wrote: Full stack web development is a multi-discipline area that demands a high level of knowledge and skill to architect a working application.  IMO, the vast majority of all web developers are not qualified to be doing it. We, ourselves, might be

Re: [racket-users] Does Racket support tail call elimination?

On 11/12/2018 4:59 PM, Matthias Felleisen wrote: > On Nov 12, 2018, at 4:53 PM, George Neuner wrote: > > I agree re: *explaining* the behavior in the browser. I don't necessarily agree that either side needs continuations in order to *implement* the behavior. Nor do I agree that

Re: [racket-users] Does Racket support tail call elimination?

On 11/12/2018 3:54 PM, Matthias Felleisen wrote: > On Nov 12, 2018, at 2:22 PM, George Neuner wrote: > >> PS: Why do web-servers need CPS? > > In general they don't. They need continuations, because BACK buttons, cloning of TABs and similar actions force a control f

Re: [racket-users] Does Racket support tail call elimination?

On 11/12/2018 10:45 AM, Rudi C wrote: How is mutual recursion via a loop any better than mutual recursion just by tail call elimination? You can't necessarily turn recursion into a loop using only TCE. TCE turns an ordinary call/return sequence into a non-returning jump [or fall through

Re: [racket-users] Does Racket support tail call elimination?

On 11/12/2018 5:52 AM, Rudi C wrote: Does Racket support tail call elimination? I am not asking about just tail recursion, but any tail calls. If not, how about mutual tail recursion (where two functions keep tail callin each other, aka trampoline)? Racket does tail call elimination [as

Re: [racket-users] Is this parameters-using code O(n^2)?

On 11/11/2018 1:55 PM, Christopher Lemmer Webber wrote: It struck me recently that I tend to think of parameters as O(1) when in reality they're O(n), where n is the number of frames on the stack, right? I was considering writing some code that cons'ed itself on its natural recursion, but in

Re: [racket-users] Subproceses in Windows

On 11/5/2018 11:49 AM, Sean Kemplay wrote: Hi All, I am trying to open windoes explorer from Racket using the following - (system* "cmd" "start" "explorer.exe") However it is not working and #f is being returned. This works fine from Go and even VBScript! Anyone know what I am missing?

Re: [racket-users] Places and many cores? (File descriptor limit?)

On 11/5/2018 9:57 AM, Matt Jadud wrote: On Sun, Nov 4, 2018 at 5:30 PM George Neuner <mailto:gneun...@comcast.net>> wrote: One .zo per distributed place is just one descriptor per process.  Again insignificant because you have 4K per process. It's apparent that

Re: [racket-users] Places and many cores? (File descriptor limit?)

On 11/4/2018 4:47 PM, Matt Jadud wrote: On Sun, Nov 4, 2018 at 2:17 PM George Neuner <mailto:gneun...@comcast.net>> wrote: Are you using in-process places or distributed places?   In-process places are just OS threads in the same process. Distributed p

Re: [racket-users] Places and many cores? (File descriptor limit?)

On 11/4/2018 12:18 PM, Matt Jadud wrote: I have some code that is unhappy.  I suspect I'm running into an OS-level resource limit. I'm working with an Intel Phi machine running CentOS that reports 256 cores. It is built using the Intel Xeon Phi 7210, which suggests that it has four, 64-core

Re: [racket-users] Doing file I/O from within a macro

On 11/1/2018 8:32 PM, Robby Findler wrote: DrRacket disallows network and filesystem access during its online expansion. Partly for security reasons and partly because it seems unlikely that the code one writes that does that would be kill safe. You might be able to bike the abstractions you

Re: [racket-users] Doing file I/O from within a macro

Hi Alex, On 11/1/2018 6:57 PM, Alex Knauth wrote: Is it possible to create a temporary file, write to it, run a command on it, and the possibly delete the file from within a macro? Yes it is possible [see below].  What you need to do depends on whether you want to keep the file open in

Re: [racket-users] gzip/gunzip through pipe is blocking

On 10/30/2018 12:56 PM, 'Paulo Matos' via Racket Users wrote: On 30/10/2018 17:07, George Neuner wrote: > > On 10/30/2018 11:32 AM, 'Paulo Matos' via Racket Users wrote: >> I have quite a few large files that I want to gzip to a single file >> (without an intermed

Re: [racket-users] gzip/gunzip through pipe is blocking

On 10/30/2018 11:32 AM, 'Paulo Matos' via Racket Users wrote: I have quite a few large files that I want to gzip to a single file (without an intermediate concatenation) and then later gunzip. I don't think you can do that - at least not without other software.  gzip/gunzip are meant to

Re: [racket-users] How to download image using net/http-client?

On 10/17/2018 9:06 AM, George Neuner wrote: But be aware that you may run into images that do *^NOT* have Content-Length  set.  Many sites assume images are only for display by the browser. Sorry.  Should have been  'do not' Gorge -- You received this message because you are subscribed

Re: [racket-users] How to download image using net/http-client?

On 10/16/2018 4:02 PM, Philippe Mechaï wrote: Indeed the issue is with your call to pipe-content-length which is to be used with pipes and is not the Content-Length header returned when doing HTTP requests. The Content-Length can be found in the list of headers returned by the call to

Re: [racket-users] Re: Looking for suggestions: GUI failure

On 10/15/2018 7:36 AM, Dan Muller wrote: On Sunday, October 14, 2018 at 9:20:42 PM UTC-4, Alex Harsanyi wrote: However, I don't think it is a good idea to create many widgets dynamically in event callbacks, than just leave them around to be garbage collected, which your example

Re: [racket-users] Re: Looking for suggestions: GUI failure

On 10/15/2018 7:36 AM, Dan Muller wrote: I was a little fuzzy on the 'deleted' status of controls and wasn't sure if that sort of thing would work. (I guess the docs are reasonably clear that this is an explicit status of children, but it's obfuscated by the fact that you can't read or set

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

Hi Philip, Sorry for the delay in responding ... busy day. On 10/14/2018 7:09 AM, Philip McGrath wrote: On Sun, Oct 14, 2018 at 5:30 AM George Neuner <mailto:gneun...@comcast.net>> wrote: You are absolutely correct that in typical usage globals are not closed over ...

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

On 10/13/2018 9:43 PM, Philip McGrath wrote: On Sat, Oct 13, 2018 at 6:32 PM George Neuner <mailto:gneun...@comcast.net>> wrote: Remember that a continuation is not a simple thing - in order to resume a program from a particular point, the entire state of the current c

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

Hi Marc, On 10/13/2018 3:37 PM, Marc Kaufmann wrote: Hi George, thanks, this is incredibly helpful. On Sat, Oct 13, 2018 at 9:11 PM George Neuner <mailto:gneun...@comcast.net>> wrote: : 3) results from the initial search are written into a dedicated table in the

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

Hi Marc, On 10/13/2018 12:17 PM, Marc Kaufmann wrote: On Sat, Oct 13, 2018 at 5:49 PM George Neuner <mailto:gneun...@comcast.net>> wrote: When the program is operating normally, are you seeing *different* continuation URLs every time you execute the same send/suspend/...

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

Hi Marc, On 10/13/2018 10:42 AM, Marc Kaufmann wrote: Thanks George and Philip. George, while I am sure that in some places I allow using continuations after a delay, that's not what I meant. What I feel is happening (with little evidence, mind you) is that, when I come back to my website

Re: [racket-users] Web server hits "Sorry, this page has expired. Please go back."

On 10/13/2018 9:27 AM, Marc Kaufmann wrote: Hi all, I am running the Racket web server with continuations and I keep getting "Sorry, this page has expired. Please go back." rather sporadically. I can't seem to figure out why and when this happens. I get it more on my local server running on

Re: [racket-users] GUI in Racket

On 10/11/2018 10:16 PM, Jeyron A.C wrote: Even so I have another doubt, and it is like using the menu bar in a simple and useful way. I have my code: (define menu-volunteers (new menu%      [label "& Volunteers"]      [parent menu-bar])) (define my_item_agregar_volun    (new menu-item%  

Re: [racket-users] GUI in Racket

On 10/11/2018 8:09 PM, Jeyron A.C wrote: Hello. Receive a greeting from me. To tell the truth I need someone who knows in general how to work the interface in rackert, in my case what I would like to explain to me is how to efficiently use the menubar in racket. The idea is to create a

Re: [racket-users] Re: distributed places on remote host

Hi Cam, On 10/11/2018 8:21 AM, Cam wrote: For some reason, I had the impression (not at all backed up by any of the documentation, in any of the documentation, in retrospect) that the code would be automatically transmitted over the network to the remote node. Thanks, George. Glad it's

Re: [racket-users] Re: distributed places on remote host

Hi Cam, On 10/10/2018 5:03 PM, Cam wrote: I took a packet capture and the only interesting thing I was able to find in it was a conversation like this: localmachine->remotemachine: > #s(dcgm 11 -1 -1 "")#s(dcgm 9 -1 (dynamic-place #"/home/cam/tmp/racket-distributed-places-test/my-worker.rkt"

[racket-users] Re: Places code not using all the CPU

On Mon, 8 Oct 2018 15:39:11 -0400, James Platt wrote: >I wonder if this has anything to do with mitigation for Spectre, >Meltdown or the other speculative execution vulnerabilities that have >been identified recently. I understand that some or all of the >patches affect the performance of

Re: [racket-users] Places code not using all the CPU

On 10/5/2018 10:32 AM, Matthew Flatt wrote: At Fri, 5 Oct 2018 15:36:04 +0200, Paulo Matos wrote: > Again, I am really surprised that you mention that places are not > separate processes. Documentation does say they are separate racket > virtual machines, how is this accomplished if not by

Re: [racket-users] Capturar valor de retorno da query Racket

On 9/27/2018 4:07 PM, Vincent St-Amour wrote: Olá, Se eu entendi sua pergunta, a função `dict-ref` é o que você quer: (dict-ref (query ..) 'insert-id) Vincent Yes, that will work on the alist.  But first you have to get the alist out of the simple-result struct. George -- You

Re: [racket-users] Capturar valor de retorno da query Racket

Hi, On 9/27/2018 3:24 PM, dev.vide...@gmail.com wrote: Olá, sou iniciante no racket. Gostaria de capturar o valor *insert-id* que retorna em um uma struct chama simple-result  da query

[racket-users] Re: Licence guidance

On Mon, 24 Sep 2018 20:18:15 +0100, er...@snafu.de wrote: >Are you sure that's a wise choice of license? I don't like either the GPL or LGPL. But as a technical matter ... >Racket does not dynamically link to Racket libraries when applications >are deployed as compiled executables - as far

Re: [racket-users] colon keywords

On 9/19/2018 11:31 AM, Alexis King wrote: I’m surprised this hasn’t been discussed yet: I'm not.  Racket (and contributions) has so many nifty features that it could take years to browse all the documentation. On a related topic, the persistent problem with keyword search engines is: if

Re: [racket-users] colon keywords

On 9/19/2018 8:29 AM, Laurent wrote: I don't mind `#:`, but I'd prefer to write `[#:foo 5]` rather than `#:foo [foo 5]`, that is, I don't like the repetition of the name (I first came to Racket precisely to avoid repeating code). When I expressed that a few years ago, I was told it would be

Re: [racket-users] colon keywords

ands so I'll repeat it here: (more below) On Sat, 21 Nov 2015 18:06:29 -0500, George Neuner wrote: I actually prefer the #: syntax, but what I would like is support for "existence" keywords - i.e. keywords with no argument - where the only thing you care about is whether or not the keywor

Re: [racket-users] Semaphore-count

On 9/4/2018 11:46 AM, George Neuner wrote: AFAIK there is no way to simply 'check' if the semaphore is available. I was wrong - there is a way using events: semaphore-peek-evt  can check whether a semaphore is ready without affecting its counter. https://docs.racket-lang.org/reference

Re: [racket-users] Semaphore-count

On 9/4/2018 8:31 AM, Craig Allen wrote: I saw that function, but was scared off by its documentation: Like semaphore-wait, but semaphore-try-wait? never blocks execution. If sema’s internal counter is zero, semaphore-try-wait? returns #f immediately without decrementing the counter. If

Re: [racket-users] Using match on hash tables with optional keys

On 8/30/2018 11:36 AM, David Storrs wrote: I'd like to be able to write something like this: (match (hash 'a 1 'b 2)   [(hash-table ('a a) ('b b) ('c c))  (list a b c)]) ...except with something that says "if 'c isn't present, that's fine.  Use this value instead." I've gone through the

Re: [racket-users] Memory usage on Linux

On 8/26/2018 6:43 PM, Jonathan Simpson wrote: The fact that Racket isn't releasing the memory back to the OS appears to be causing the system to eventually run out of physical pages. Is this a cloud server?  Is the problem that the "out-of-memory" (OOM) handler is killing processes?  That

Re: [racket-users] Memory usage on Linux

On 8/26/2018 7:43 PM, Matthew Flatt wrote Racket's memory manager does not immediately release pages back to the OS (i.e., unmap them) after a GC. In its current configuration, the GC releases a page at the beginning of a major GC only if the page was unused at the *start* of the previous GC.

Re: [racket-users] Memory usage on Linux

On 8/26/2018 12:55 PM, Jonathan Simpson wrote: I have a Racket application that I need to run in a fairly memory constrained environment(1 GB ram) and I've ran into something I don't quite understand. The application is deserializing a fairly large data structure from disk on startup. After

Re: [racket-users] C level bit manipulation - Racket Manifesto

On 8/13/2018 10:02 AM, 'Paulo Matos' via Racket Users wrote On 11/08/18 19:41, Sam Tobin-Hochstadt wrote: > There are basically two differences between the `unsafe-lsb` function > in Racket and the C one: > - the Racket calling convention vs the C calling convention > - the instruction used

Re: [racket-users] Re: parameterize and keyword - doable?

On 8/4/2018 7:24 AM, Philip McGrath wrote: On Sat, Aug 4, 2018 at 5:26 AM, George Neuner <mailto:gneun...@comcast.net>> wrote: On Sat, 4 Aug 2018 00:08:46 -0500, Philip McGrath mailto:phi...@philipmcgrath.com>> wrote: >and you can create a function that

[racket-users] Re: parameterize and keyword - doable?

n. >A few points for the list, though: > >On Fri, Aug 3, 2018 at 10:53 PM, George Neuner wrote: > >> (define mykey (make-parameter (string->keyword "#:unless"))) >> > >Using (string->keyword "#:unless") will produce the same keyword v

Re: [racket-users] parameterize and keyword - doable?

On 8/3/2018 11:52 AM, Sanjeev Sharma wrote: make a keyword useable as the parameter-expr in a parameterize expression. for example, If I need a similar #:unless cause for  a bunch of for expressions It's not a current issue, but would be good  to have in the toolbox for next time. If I'm

[racket-users] Re: Parameters considered often harmful

On 8/2/2018 1:24 PM, 'John Clements' via Racket Users wrote: I hate to turn a little question into a big one, but… are parameters the right choice, here? It seems to me that optional parameters would be more suitable. Unfortunately, I’ve been on the other side of this fence, too: parameters

Re: [racket-users] parameterize and keyword - doable?

On 8/2/2018 7:45 PM, Sanjeev Sharma wrote: can racket's  #: keywords be finagled / coerced into a parameterizable form? ??? Certainly you can pass a parameter to a keyword argument, and/or make a parameter the default value of a keyword argument.  And you can use an argument to

Re: [racket-users] Racket 7 multi core support

Hi Sam, On 5/21/2018 11:42 PM, Sam Tobin-Hochstadt wrote: First, the default build of Racket 7 (according to the plan Matthew posted to the racket-dev list on Feb 20) will have the new in-Racket expander, but the default will not be to use Chez Scheme's runtime. Second, the "cs" variant of

Re: [racket-users] Racket 7 multi core support

On 5/21/2018 12:00 PM, Piyush Katariya wrote: what if i dont wish to juggle between Threads and Places to leverage all CPU cores ? Just use Thread abstraction. Chez Scheme page says it can possible run on multi core, so I believe it must be possible for Racket 7 to do so ???

Re: [racket-users] Racket 7 multi core support

On 5/21/2018 10:31 AM, Piyush Katariya wrote: Will Racket 7 support utilizing multi-core CPUs in one process instance ? Sort of.  The Racket VM implements userspace threads on a single core.  However a single OS process can host multiple instances of the VM which can communicate with each

Re: [racket-users] GUI problem -- main window loosing focus when two dialog boxes are opened

Hi Alex, fwiw:  I tried with 32-bit 6.11 on Win7 and it messes up also. On 5/8/2018 6:24 AM, Alex Harsanyi wrote: I had a look at the application windows using Spy++ and all three windows (the main frame and the two dialog ones) are toplevel windows, as expected; however they are linked

Re: [racket-users] GUI problem -- main window loosing focus when two dialog boxes are opened

Hi Alex, On 5/8/2018 6:24 AM, Alex Harsanyi wrote: On Tuesday, May 8, 2018 at 2:08:02 PM UTC+8, gneuner2 wrote: So I guess the 1st question to answer is: does the GDI object have the correct parent HWND?  [The Racket dialog% object has a parent, but does the underlying

Re: [racket-users] GUI problem -- main window loosing focus when two dialog boxes are opened

Hi Alex, On 5/7/2018 8:46 PM, Alex Harsanyi wrote: I have a problem with the Racket GUI where the main application window looses focus if two dialog boxes are opened than closed.  The problem occurs when the main window opens the first dialog box and the first dialog box opens the second one

Re: [racket-users] IEEE 754 single precision float support

On 4/11/2018 7:03 PM, Philip McGrath wrote: From one following along who knows fairly little about floating-point math (the Toronto/McCarthy paper looks very informative!): On Tue, Apr 10, 2018 at 12:13 AM, George Neuner <gneun...@comcast.net <mailto:gneun...@comcast.net&g

Re: [racket-users] IEEE 754 single precision float support

Sorry for the delay.  My ISP's service has been flaky of late.  It was down much of Tuesday.  I'm still getting caught up. On 4/10/2018 2:30 PM, d...@insomniacgames.com wrote: How long do you want to wait for "truth" calculations.  Done using either rationals (software bigint /

Re: [racket-users] IEEE 754 single precision float support

On 4/10/2018 1:36 AM, d...@insomniacgames.com wrote: For the applications I work on, double precision floats are too costly to use; although the CPU cycle count to operate on doubles tend to be the same as single precision floats on modern hardware, the bandwidth cost is too prohibitive. We

<    1   2   3   4   5   6   >