December 2017 - Haskell-Cafe

The Definition of Haskell
by Todd Wilson 18 Dec '17

18 Dec '17

Why doesn't Haskell (or at least "core" Haskell) have a formal definition and safety result the way Standard ML does [1], [2]? Is it just that no one has gotten around to producing them, or because there are fundamental difficulties that stand in the way of completing such a project? Todd Wilson [1] Robin Milner, Mads Tofte, Robert Harper, and David MacQueen. The Definition of Standard ML (Revised). MIT Press, 1997. [2] Daniel K. Lee , Karl Crary , Robert Harper, "Mechanizing the Metatheory of Standard ML", http://www.cs.cmu.edu/~dklee/tslf/

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Managing package release workflow
by Clinton Mead 18 Dec '17

18 Dec '17

Hi All I've already got a few packages on hackage <https://hackage.haskell.org/user/clinton>, but I'd like to upload a few more, but I'm finding the workflow management particularly excessive. Here's what I'd like to do roughly: 1. Choose a number of stack snapshots I'd like my package to successfully build and test against. 2. Automatically apply appropriate version bounds to dependencies in my cabal file based on those snapshots. 3. When these changes are pushed to Github, attempt to compile them using Travis CI, against all the stack snapshots chosen. 4. If we do a push to a particular branch or with particular tag, this signifies we're attempting a release. Attempt to compile using Travis CI, perform the tests. If the compile and tests are successful, push a separate commit, adjust the "source-repository" field in github to point to that release commit (not to master) and upload to hackage. I'm currently doing all of this manually but it's increasingly a bit of a pain. Is there tooling to help me automate this? Thanks, Clinton

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Who can send a patche to vim project?
by Takenobu Tani 18 Dec '17

18 Dec '17

Hi cafe, Who can send a patche to vim project? I'd like to update vim syntax file (haskell.vim) to fix numeric literals. I read the vim `CONTRIBUTING.md` file [1]. It instructs me to contact the maintainer of each files. In the header of `haskell.vim`, the maintainor of `haskell.vim` is haskell-cafe@ML. [2] Who is the maintainer of `haskell.vim`? I'd like to make fix on numeric literals extension: [3] * BinaryLiterals * HexFloatLiterals * NumericUnderscores I prepared two kinds of patches. * Exact pattern version [4] * Fast (but approximate) pattern version [5] I visually checked patches with the these files [6][7]. Could you send a patch of [4] or [5] to vim project? P.S. I have already sent patches to two projects. * `language-haskell` for atom and linguist [8] You can already use it on atom. Linghist (which is used from github) will apply it soon. * `pygments` [9] It is pending review. [1]: https://github.com/vim/vim/blob/master/CONTRIBUTING.md#syntax-indent-and-ot… [2]: https://github.com/vim/vim/blob/master/runtime/syntax/haskell.vim#L3 [3]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0009-n… [4]: https://github.com/vim/vim/compare/master...takenobu-hs:syntax-haskell-lite… [5]: https://github.com/vim/vim/compare/master...takenobu-hs:syntax-haskell-lite… [6]: https://github.com/takenobu-hs/ghc/blob/squashed-numeric-underscores/testsu… [7]: https://github.com/takenobu-hs/ghc/blob/squashed-numeric-underscores/testsu… [8]: https://github.com/atom-haskell/language-haskell/commit/f90eb7d8662493536f5… [9]: https://bitbucket.org/birkenfeld/pygments-main/issues/1399/update-haskell-w… Regards, Takenobu

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Is Haskell the best programming language?
by Henning Thielemann 15 Dec '17

15 Dec '17

I just got to know that there is a card game (code quartett) that lets players find out what language is the best: http://codequartett.de/index-en.html :-)

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Announce: Haskell Platform 8.2.2
by Gershom B 14 Dec '17

14 Dec '17

On behalf of the Haskell Platform team, I'm happy to announce the release of Haskell Platform 8.2.2 Now available at https://www.haskell.org/platform/ This includes GHC 8.2.2, cabal-install 2.0.0.1, and stack 1.6.1, all with many bugfixes since the last platform release. A full list of contents is available at https://www.haskell.org/platform/contents.html Thanks to all the contributors to this release, thanks to all the package and tool maintainers and authors, and a big thanks to the GHC team for all their hard work. There are currently no 32 bit Windows builds available. We expect to have those out in short order. A list of new GHC changes is available at: https://ghc.haskell.org/trac/ghc/blog/ghc-8.2.2-released A list of cabal changes is available at: https://hackage.haskell.org/package/cabal-install-2.0.0.1/changelog The cabal documentation page is at: https://www.haskell.org/cabal/users-guide/ A list of stack changes is at: https://docs.haskellstack.org/en/stable/ChangeLog/ The stack documentation page is at: https://docs.haskellstack.org/en/stable/README/ Happy Haskell Hacking all, Gershom

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25th Anniversary of GHC
by Henk-Jan van Tuyl 14 Dec '17

14 Dec '17

L.S., The eleventh of this month was the 25th anniversary of GHC: the first full release of GHC was announced at 1992-12-11; the version number was 0.10 and a Sun 4 workstation was needed to run GHC. The announcement can be read at: http://code.haskell.org/~dons/haskell-1990-2000/msg00960.html Regards, Henk-Jan van Tuyl -- Message from Stanford University: Folding@home What if you could share your unused computer power to help find a cure? In just 5 minutes you can join the world's biggest networked computer and get us closer sooner. Watch the video. http://foldingathome.stanford.edu/ -- http://members.chello.nl/hjgtuyl/tourdemonad.html Haskell programming --

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[ANN] Experimental Windows GHC 8.2.2+ 64-bit binary release. Binary compatible with Visual C/Native Windows SDK.
by kyra 13 Dec '17

13 Dec '17

An experimental Windows GHC 8.2.2+ 64-bit Visual C/Native Windows SDK binary compatible distribution is released. The distro is based on and targets Microsoft Visual C runtime and native Windows SDK. The code it produces is statically linkable with Microsoft Visual C and native Windows SDK libraries. Both Visual Studio 2013 and 2017/2015 are supported. Distribution site: https://awson.github.io/ghc-nw/. Cheers, K. Briantsev (aka awson)

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how to run in bounded space?
by Johannes Waldmann 12 Dec '17

12 Dec '17

Dear Cafe. is there an easy way (in GHC Haskell) to run a computation until it (times out or) requires more than X MB of heap? (the main program has a larger heap, but the computation should use some part of it only) This would be nice for automated tests with predictable resources (time and space). There is Control.Timeout. I guess I want Control.Spaceout. - J.

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Unsubscribe
by Peter Althainz 11 Dec '17

11 Dec '17

Am 11.12.2017 1:32 nachm. schrieb <haskell-cafe-request(a)haskell.org>: Send Haskell-Cafe mailing list submissions to haskell-cafe(a)haskell.org To subscribe or unsubscribe via the World Wide Web, visit http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe or, via email, send a message with subject or body 'help' to haskell-cafe-request(a)haskell.org You can reach the person managing the list at haskell-cafe-owner(a)haskell.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Haskell-Cafe digest..." Today's Topics: 1. ANN: New Haskell.org Committee Members (Gershom B) 2. How to call constructor from Template Haskell (Baa) 3. Who can send a patche to vim project? (Takenobu Tani) 4. Re: Haskell IDE Engine logo poll (Alan & Kim Zimmerman) ---------------------------------------------------------------------- Message: 1 Date: Mon, 11 Dec 2017 01:36:50 -0500 From: Gershom B <gershomb(a)gmail.com> To: haskell-cafe <haskell-cafe(a)haskell.org>, haskell-community(a)haskell.org, Tikhon Jelvis <tikhon(a)jelv.is>, Ryan Trinkle <ryan.trinkle(a)gmail.com>, george(a)wils.online Subject: [Haskell-cafe] ANN: New Haskell.org Committee Members Message-ID: <CAM8RHpGY+Z_kG0cM=usFDEqX4UNgabWecMv_ZEiP85WmgritOg(a)mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Following the self-nomination period and discussion, the Haskell.org committee has selected the following members for a new three-year term, expiring 2020: * Tikhon Jelvis * Ryan Trinkle (reappointment) * George Wilson As per the rules of the committee, this discussion was held among the current members of the committee, and the outgoing members of the committee who were not seeking reappointment. Thank you to all the many candidates who submitted a self-nomination. We received a number of strong nominations. We would encourage all those who nominated themselves to consider self-nominating again in the future. The outgoing members are: John Wiegley and Alan Zimmerman. Thanks both for your service! Regards, Gershom ------------------------------ Message: 2 Date: Mon, 11 Dec 2017 14:03:48 +0200 From: Baa <aquagnu(a)gmail.com> To: Haskell Cafe <haskell-cafe(a)haskell.org> Subject: [Haskell-cafe] How to call constructor from Template Haskell Message-ID: <20171211140348.2a1610b1@Pavel> Content-Type: text/plain; charset=US-ASCII Hello All! May be topic is not for Haskell beginners, so I'll re-send it to Cafe. I have function which constructs some data type. It has signature `Name -> Q [Dec]`. Somewhere in its body I'm extracting constructors of another type with pattern-matching: case tyCons of DataD ctx nm tyVars mbKind cs derivs -> ... Type of those constructors `cs` instantiates some class like this: class MyClass a where specialValue :: a So, I'm iterating over those `cs` but I want to skip one of them which is equal to `specialValue`. Something like this: [c | c <- cs, c /= specialValue] How to do this with Template Haskell's `Con` type (`c`::Con)? I can't simply call it to compare created value with a `specialValue`. === Best regards, Paul ------------------------------ Message: 3 Date: Mon, 11 Dec 2017 21:16:25 +0900 From: Takenobu Tani <takenobu.hs(a)gmail.com> To: haskell-cafe <haskell-cafe(a)haskell.org> Subject: [Haskell-cafe] Who can send a patche to vim project? Message-ID: <CAPB_NvzMGZS3OYEAXuqRCXyx_hsXYf8JaCj0S6cJ=VJeH-KwtQ(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" Hi cafe, Who can send a patche to vim project? I'd like to update vim syntax file (haskell.vim) to fix numeric literals. I read the vim `CONTRIBUTING.md` file [1]. It instructs me to contact the maintainer of each files. In the header of `haskell.vim`, the maintainor of `haskell.vim` is haskell-cafe@ML. [2] Who is the maintainer of `haskell.vim`? I'd like to make fix on numeric literals extension: [3] * BinaryLiterals * HexFloatLiterals * NumericUnderscores I prepared two kinds of patches. * Exact pattern version [4] * Fast (but approximate) pattern version [5] I visually checked patches with the these files [6][7]. Could you send a patch of [4] or [5] to vim project? P.S. I have already sent patches to two projects. * `language-haskell` for atom and linguist [8] You can already use it on atom. Linghist (which is used from github) will apply it soon. * `pygments` [9] It is pending review. [1]: https://github.com/vim/vim/blob/master/CONTRIBUTING.md# syntax-indent-and-other-runtime-files [2]: https://github.com/vim/vim/blob/master/runtime/syntax/haskell.vim#L3 [3]: https://github.com/ghc-proposals/ghc-proposals/blob/ master/proposals/0009-numeric-underscores.rst#new-syntax-this-proposal [4]: https://github.com/vim/vim/compare/master...takenobu-hs: syntax-haskell-literal-exact [5]: https://github.com/vim/vim/compare/master...takenobu-hs: syntax-haskell-literal-fast [6]: https://github.com/takenobu-hs/ghc/blob/squashed-numeric- underscores/testsuite/tests/parser/should_run/NumericUnderscores0.hs [7]: https://github.com/takenobu-hs/ghc/blob/squashed-numeric- underscores/testsuite/tests/parser/should_run/NumericUnderscores1.hs [8]: https://github.com/atom-haskell/language-haskell/commit/ f90eb7d8662493536f54898e52b4c7b1dc96de41 [9]: https://bitbucket.org/birkenfeld/pygments-main/issues/1399/update-haskell- with-lexer-for-numeric Regards, Takenobu

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Re: [Haskell-cafe] Maintenance of streaming and streaming-bytestring
by David Feuer 11 Dec '17

11 Dec '17

I've added you as a member of haskell-streaming. Feel free to transfer the repo. On Sat, Dec 9, 2017 at 10:10 AM, Boespflug, Mathieu <m(a)tweag.io> wrote: > I'd like to contributed streaming-binary to the streaming GitHub org, if > you're up for it. > > http://hackage.haskell.org/package/streaming-binary > > Best, > > -- > Mathieu Boespflug > Founder at http://tweag.io. > > On 17 September 2017 at 01:24, David Feuer <david.feuer(a)gmail.com> wrote: >> >> Ah, right. Then yes, that sounds like a great approach. >> >> On Sep 15, 2017 1:23 PM, "Carter Schonwald" <carter.schonwald(a)gmail.com> >> wrote: >>> >>> GitHub has a transfer repo ownership toggle you can do to move the main >>> repo and it's assets >>> >>> On Fri, Sep 15, 2017 at 1:05 PM David Feuer <david.feuer(a)gmail.com> >>> wrote: >>>> >>>> Having an organization (with multiple owners and members) makes for much >>>> smoother transitions when maintainers change. That goes triple for >>>> unexpected changes. There's (still!) no really good way to migrate an issue >>>> tracker or PRs from one repository to another. Unfortunately, for that same >>>> reason, I believe that actually moving your project to the organization will >>>> be quite unpleasant if there are more than a few open tickets. And if there >>>> are more than a few closed tickets, then preserving history in a useful >>>> history seems hard too. Maybe someone else knows a reason this isn't >>>> actually terrible. >>>> >>>> David >>>> >>>> On Sep 14, 2017 1:10 AM, "Ivan Lazar Miljenovic" >>>> <ivan.miljenovic(a)gmail.com> wrote: >>>> >>>> Since you've seem to set this up as an organisation, would you be >>>> interested in my moving over the various streaming libraries I have >>>> there as well? >>>> >>>> On 14 September 2017 at 03:31, Andrew Martin <andrew.thaddeus(a)gmail.com> >>>> wrote: >>>> > The streaming and streaming-bytestring libraries are now being >>>> > maintained >>>> > here: https://github.com/haskell-streaming >>>> > >>>> > On Tue, Sep 12, 2017 at 4:50 PM, Andrew Martin >>>> > <andrew.thaddeus(a)gmail.com> >>>> > wrote: >>>> >> >>>> >> Thanks adding me as a maintainer. I'm new to this process, so I >>>> >> appreciate >>>> >> the tip about admin(a)hackage.haskell.org as well. >>>> >> >>>> >> -Andrew Martin >>>> >> >>>> >> On Tue, Sep 12, 2017 at 3:57 PM, Erik Hesselink <hesselink(a)gmail.com> >>>> >> wrote: >>>> >>> >>>> >>> Hi Andrew, >>>> >>> >>>> >>> We usually allow about 3 weeks for the maintainer to respond. Since >>>> >>> that >>>> >>> time has now passed I've added you as a maintainer for streaming and >>>> >>> streaming-bytestring. Let me know if there's anything else you need. >>>> >>> >>>> >>> For others looking to take over a package in the future, please CC >>>> >>> admin(a)hackage.haskell.org, there's a higher chance I'll see it there >>>> >>> than >>>> >>> just on the email lists. >>>> >>> >>>> >>> Regards, >>>> >>> >>>> >>> Erik (hackage admin) >>>> >>> >>>> >>> On 12 September 2017 at 20:18, Andrew Martin >>>> >>> <andrew.thaddeus(a)gmail.com> >>>> >>> wrote: >>>> >>>> >>>> >>>> Are there any further steps that I can take? >>>> >>>> >>>> >>>> On Thu, Sep 7, 2017 at 11:07 AM, Andrew Martin >>>> >>>> <andrew.thaddeus(a)gmail.com> wrote: >>>> >>>>> >>>> >>>>> David Feuer brought this up two weeks ago [0]. The maintainer of >>>> >>>>> streaming and streaming-bytestring has been unreachable, and >>>> >>>>> provided his >>>> >>>>> continued absence, I would like to become a maintainer of these >>>> >>>>> two >>>> >>>>> libraries. I have put up PRs fixing issues [1] and I've offered on >>>> >>>>> the issue >>>> >>>>> tracker to become a comaintainer [2]. I use this library a lot at >>>> >>>>> work, so I >>>> >>>>> have an interest in keeping it in good shape. >>>> >>>>> >>>> >>>>> [0] >>>> >>>>> >>>> >>>>> https://mail.haskell.org/pipermail/libraries/2017-August/028141.html >>>> >>>>> [1] https://github.com/michaelt/streaming-bytestring/pull/11 >>>> >>>>> [2] https://github.com/michaelt/streaming-bytestring/issues/19 >>>> >>>>> >>>> >>>>> -- >>>> >>>>> -Andrew Thaddeus Martin >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> -Andrew Thaddeus Martin >>>> >>>> >>>> >>>> _______________________________________________ >>>> >>>> Libraries mailing list >>>> >>>> Libraries(a)haskell.org >>>> >>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries >>>> >>>> >>>> >>> >>>> >> >>>> >> >>>> >> >>>> >> -- >>>> >> -Andrew Thaddeus Martin >>>> > >>>> > >>>> > >>>> > >>>> > -- >>>> > -Andrew Thaddeus Martin >>>> > >>>> > _______________________________________________ >>>> > Haskell-Cafe mailing list >>>> > To (un)subscribe, modify options or view archives go to: >>>> > http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe >>>> > Only members subscribed via the mailman list are allowed to post. >>>> >>>> >>>> >>>> -- >>>> Ivan Lazar Miljenovic >>>> Ivan.Miljenovic(a)gmail.com >>>> http://IvanMiljenovic.wordpress.com >>>> _______________________________________________ >>>> Haskell-Cafe mailing list >>>> To (un)subscribe, modify options or view archives go to: >>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe >>>> Only members subscribed via the mailman list are allowed to post. >>>> >>>> >>>> _______________________________________________ >>>> Haskell-Cafe mailing list >>>> To (un)subscribe, modify options or view archives go to: >>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe >>>> Only members subscribed via the mailman list are allowed to post. >> >> >> _______________________________________________ >> Libraries mailing list >> Libraries(a)haskell.org >> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries >> >

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