GHC Users,
I am working on adding proper support for GADTs in Template Haskell. By proper
I mean that GADTs
data constructors will no longer be encoded using H98 data constructors, but
will be represented
explicity.
GADTs allow to declare several constructors with the same signature:
data
One thing to keep in mind is that while cpphs will solve some problems of
system-cpp, it will also
bring problems of its own. I, for one, have run into problems with it when
installing Agda. There
is a very long thread here:
https://lists.chalmers.se/pipermail/agda/2014/006975.html
and twice
recall someone
else reported
being affected by the same problem. So, until that problem is solved I would
say it is a blocker
as it would essentialy make development of GHC impossible for some people.
Janek
On 6 May 2015 at 06:38, Jan Stolarek jan.stola...@p.lodz.pl wrote:
One thing to keep
:19 AM, Jan Stolarek jan.stola...@p.lodz.pl wrote:
An update frrom my second machine, this time with 4GB of RAM. Compiling
Agda ran out of memory (again Agda.TypeChecking.Serialise module) and I
had to kill the build. But once I restarted the build the module was
compiled succesfully
.
This looks like some kind of memory leak in GHC.
Janek
Dnia środa, 1 kwietnia 2015, Jan Stolarek napisał:
Forall hi,
I just uprgaded both of my machines to use GHC 7.10.1. I keep sandboxed
installations of GHC and this means I had to rebuild Agda and Idris because
the binaries built with GHC
I'm curious why the amount of RAM is relevant as all of our OS have virtual
memory so it is only the size of the heap and the amount of swap that
should be relevant for an Out Of Memory error, right? How big is your heap?
Amount of RAM should only affect speed (i.e. if there is excessive
Forall hi,
I just uprgaded both of my machines to use GHC 7.10.1. I keep sandboxed
installations of GHC and
this means I had to rebuild Agda and Idris because the binaries built with GHC
7.8.4 were stored
inside deactivated 7.8.4 sandbox. Sadly, I had problems building both Agda and
Idris
Austin, links to x86_64 linux versions for CentOS don't work.
Janek
Dnia piątek, 27 marca 2015, Austin Seipp napisał:
==
The (Interactive) Glasgow Haskell Compiler -- version 7.10.1
The current version of cabal-install located at Hackage can not be
installed for the RC because of the following dependency error:
Setup: At least the following dependencies are missing:
filepath =1.0 1.4
The problem is that cabal-install require filepath 1.4, while the RC
ships with
Thank you Adam.
One example is https://github.com/haskell/vector/issues/34
Yes, this looks like an example where injectivity will work. One question here:
how does one build
vector with GHC HEAD? I tried but failed because of dependencies.
I see lots of potential uses in HList. For example
Haskellers,
I am finishing work on adding injective type families to GHC. I know that in
the past many people
have asked for this feature. If you have use cases for injective type families
I would appreciate
if you could show them to me. My implementation has some restrictions and I
want to
.lhs = Literate Haskell
So maybe .mhs = Markdown Haskell instead of .lhs+md?
Jan
___
Glasgow-haskell-users mailing list
Glasgow-haskell-users@haskell.org
http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
On a somewhat related note, I'd love to be able to do this in Haskell:
import Basics.Nat renaming (_≥_ to _≥ℕ_)
(this is taken from Agda).
Janek
Dnia poniedziałek, 29 września 2014, Herbert Valerio Riedel napisał:
Hello *,
Here's a situation I've encountered recently, which mades me wish
Haskellers,
recently I've been looking into the possibility of creating some new
optimisations for GHC. These
would be mostly aimed at list comprehensions. Here's where I need your help:
1. Do you have complex list comprehensions usage examples from real code? By
complex I mean
nested list
Hi all,
GHC 7.8 adds --show-options flag that prints all supported command line flags
on standard output.
This can be used to enable autocompletion of command line options for ghc in
shells that support
autocompletion. If you're using bash add this snippet to your ~/.bashrc file:
START
#
Thanks Philip.
ps - I tried to register on trac to add this info to your page but my
registration was marked as spam (even after answering a math question)
I believe you have to contact Herbert about that (CC'd).
In the meantime I added this information to GHC wiki, although it would be nice
with more intimate knowledge of GHC
development might be able to speak on this issue.
Regards,
Tyler Huffman
On Thu, Feb 6, 2014 at 1:50 PM, Jan Stolarek jan.stola...@p.lodz.pl wrote:
I had the same problem on Debian Squeeze:
https://ghc.haskell.org/trac/ghc/ticket/8666
What is your
I had the same problem on Debian Squeeze:
https://ghc.haskell.org/trac/ghc/ticket/8666
What is your distro?
CCing ghc-devs.
Janek
Dnia czwartek, 6 lutego 2014, Sergei Meshveliani napisał:
Dear GHC team,
I am trying to testghc-7.8.20140130-src.tar.bz2
I make it from source with
I admit I haven't yet had the time to try out testy, but there's one thing I'm
curious about. QuickCheck can classify tests:
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
Sorry, my last email got sent too quickly. Anyway, continuing my thought. So
QuickCheck can classify tests:
+++ OK, passed 100 tests (29% Short)
Can tasty display this classification info? That was a thing I missed a lot in
test-framework and would probably motivate me to switch to tasty.
: Jan Stolarek jan.stola...@p.lodz.pl
DW: haskell-cafe@haskell.org
Wysłane: środa, 7 sierpień 2013 10:56:21
Temat: Re: [Haskell-cafe] ANNOUNCE: tasty, a new testing framework
It certainly can, but it doesn't do that yet. Should be very easy to
fix, though. Patches are welcome.
Roman
* Jan Stolarek
Oh, a new testing framework - I'm always interested in that :)
At the very least, you'll have to change module names
(Test.Framework - Test.Tasty,
Test.Framework.Providers.HUnit - Test.Tasty.HUnit, ...),
and wrap the top-level list of tests into a testGroup.
If you have type signatures,
I'd say OtherLicense because:
data License = GPL3
is different from
data License = Commercial | GPL3
I hope this analogy to Haskell data types is convincing :)
Janek
- Oryginalna wiadomość -
Od: David Sorokin david.soro...@gmail.com
Do: Vo Minh Thu not...@gmail.com
DW: Haskell
I don't know much about type families, but I recall this:
http://ghc.haskell.org/trac/ghc/ticket/5321
The bug is marked as fixed, but perhaps behaviour you observed shows that there
are other cases
where constraqint solver is slow. I'd consider reporting this as GHC bug.
Janek
Dear list,
list comprehensions and SQL-like generalized comprehensions can be used to
write queries in
Haskell. Does anyone know of any work focused on optimizing such queries? A
quick google didn't
show up anything meaningful.
Janek
___
Also, for some history, this was discussed a while back:
http://www.mail-archive.com/haskell@haskell.org/msg03721.html
Thanks for pointing me to earlier discussions on this subject - they are
enlightening :) One
particular argument against seems to be very convincing to me:
From a language
Hi all,
consider this simple reimplementation of 'elem' function:
member :: Eq a = a - [a] - Bool
member _ [] = False
member y (x:xs) | x == y= True
| otherwise = member y xs
If Haskell allowed to write pattern matching similar to Prolog then we could
write this function
You can achieve something similar with the ViewPatterns language
extension.
member _ [] = False
member x (((x ==) - True) : _) = True
member x (_ : xs) = member x xs
Hi Tillmann,
there are a couple of ways to achieve this in Haskell, for example using guards:
member :: Eq a = a - [a] -
Hi Ian,
I think it would make sense to post this on haskell-cafe. I think we can expect
larger response
from there than from glasgow-haskell-users.
Janek
Dnia wtorek, 19 marca 2013, Ian Lynagh napisał:
Hi all,
Thank you to everyone who gave us feedback on when we should release
7.8.1, and
is it possible?
The output you are looking for is in the log file:
dist/test/opencv-simple-0.1.0.0-test-all.log
It gets displayed only if something goes wrong (i.e. a test fails). If all
tests pass it's logged
to the file. I hope this helps.
Janek
Does anyone know if haksell-pkg-janitors group on github is alive? I've
submitted a pull request a
week ago but no response so far.
Janek
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
Unfortunately there doesn't seem
to be a way of getting pull request notifications.
You can get such notifications. You need to watch a repo (enabled by default if
you have push
permissions) and enable notifications for watching in Account settings -
Notification Center.
Anyway, applied all
Any opinion about whether it's better to put them
in the same or separate actual repos?
The general rule in git is that a repo should contain a single project. There
are some projects
that violate this rule - e.g. cabal stores both Cabal and cabal-install in the
same repository -
but with
Are you suggesting that the source code of these packages is moved out to
their own darcs repositories?
Exactly. This allows to use and develop these packages independently of
lambdabot and I consider
that a Good Thing. I'm also much in favor of using git, because github allows
easy
I've catalogued a list of issues on github:
https://github.com/mokus0/lambdabot/issues
Let me know if you have objections against any of them. If no then I will try
to fix them
gradually. Right now a major problem for me are exceptions in Data.Binary, but
I don't think I
will be able to fix
goodness may be outweighed by the costs of switching:
Could you specify what are those cost of switching?
Turns out the
reason for people not submitting patches had more to do with things
besides not being hosted on Github.
Of course. I don't clain this is the reason for people not
I'm happy to hear your approval.
I've spent some time yesterday cleaning up the code and writing down all things
that do not work.
The list I made is avaliable on github:
https://github.com/killy/lambdabot/issues
There are 17 open issues at the moment and I know I will not have enough
Wow, this indeed looks like a nice starting point, though I can't build
lambdabot from your repo -
seems that dice package is not on Hackage. Is this the package that you rely on:
https://github.com/serialhex/dice ?
Anyway, how would you feel about changes that I would like to make:
- move all
Dnia wtorek, 19 lutego 2013, Gwern Branwen napisał:
On Tue, Feb 19, 2013 at 5:36 PM, Jan Stolarek jan.stola...@p.lodz.pl wrote:
- remove unlambda, brainfuck and show from the repo. They are on hackage,
no need to keep them here - these packages aren't even used in the build
process.
Where
I have no objections to any of these,
Great. Then I will start making mentioned changes and sending pull requests
when I find some free
time.
though I would recommend as Gwern
hinted that if related packages are to be removed that they should also be
given new homes - I believe that the
Hi all,
as some of you may have noticed Lambdabot doesn't build on GHC 7.6.1 due to
OldException being
removed (and a few other changes). I updated the code so that it builds on
latest GHC release.
The updated code is available here:
https://github.com/killy/lambdabot/tree/upstream
It
To me, it seems that something like this should be possible -- am i being
naive? does it already exist?
During the compilation process GHC optimizes the code by performing successive
transformations of
the program. These transformations are known to preserve meaning of the program
- they
Hi all,
some time ago me and my friend had a discussion about optimizations performed
by GHC. We wrote a
bunch of nested list comprehensions that selected objects based on their
properties (e.g. finding
products with a price higher than 50). Then we rewrote our queries in a more
efficient
Would you object to this particular optimisation (replacing an algorithm
with an entirely different one) if you were guaranteed that the space
behaviour would not change?
No, I wouldn't.
Janek
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
You're right, somehow I didn't thought that DPH is doing exactly the same
thing. Well, I think
this is a convincing argument.
Janek
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
Of course that is fine. But keep in mind that all parser combinator based
libraries are based on a top-down parsing strategy which in most places,
BUT NOT ALL, fits Haskell's syntax. Try to use the chaining combinators
where-ever possible. In case of doubt you can always spy on how things are
Hi all,
I was thinking about reading An introduction to Category theory in four easy
movements available
online at http://www.cs.man.ac.uk/~hsimmons/BOOKS/books.html I noticed however
that these notes
were published as a book. Looking at the table of contents at Amazon, it seems
that
Dnia niedziela, 3 lutego 2013, Doaitse Swierstra napisał:
Use the uu-parsinglib library, which provides error messages, repairs your
errors and using its idioms definition you can even write:
inParens c = iI '(' c ')' Ii
I think you cannot get it shorter and with more functionality.
Thanks for replies guys. I indeed didn't notice that there are monads and
applicatives used in
this parser. My thought that monadic parsers are more verbose came from
Hutton's paper where the
code is definitely less readable than in example I provided.
There is one more thing that bothers me.
Dnia czwartek, 31 stycznia 2013, Ertugrul Söylemez napisał:
Remember that 'Either e' is also a monad. =)
I remember - this makes the change from Maybe to Either very easy :) Still I
found that adding
error message to every combinator and function ads a lot of boilerplate. Also,
I experince
I will be writing a parser in Haskell and I wonder how to approach the problem.
My first thought
was to use monadic parser, e.g. like the one described by Hutton and Meijer in
Monadic Parsing
in Haskell functional pearl. But then I stumbled upon this:
Thanks for a nice tutorial. A couple of months ago I spent quite some time
trying to figure out
how to write tests in Haskell, which resulted in this blog post:
http://ics.p.lodz.pl/~stolarek/blog/2012/10/code-testing-in-haskell/
Sadly there are no test-framework providers for hspec and
The only paper that comes to my mind is Wadler's Theorems for free. It's an
old one and not
exactly about rewrite rules, but it may be a good starting point.
Janek
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
Dnia piątek, 18 stycznia 2013, Petr P napisał:
for learning Hindley-Milner type inference algorithm I could recommend to
undergraduate students? The original paper is harder to understand, I'm
looking for something more didactic. The students are familiar with the
lambda calculus, natural
Hi all,
I've been reading Commentary about PrimOps and code generation and I noticed
that it is partially
outdated (e.g. references to old code gen files: compiler/codeGen/CgPrimOp.hs):
http://hackage.haskell.org/trac/ghc/wiki/Commentary/PrimOps
How about, in the source directory:
git clean -dfx
or perhaps with -X instead. You can use -n instead of -f to see what
it'd do.
Thanks! I inspected the Makefile and it turns out that there is no need for a
workaround:
make maintainer-clean
does the job.
Janek
The workaround is to link your .git directory from your build tree, like
so:
$ cd ghc-build
$ ln -s $source/.git .
where $source is your source tree.
I managed to get it working on Debian though there were some small issues.
Lndir linked .git
directory by default, but it was not
Would it be possible to change mailing list settings so that topics of emails
begin
with [glasgow-haskell-users] (and for upcoming lists: [ghc-devs],
[ghc-commits] and so on.
No quotation marks of course). It would make filtering and searching in the
mailbox easier.
Janek
I see you're using KMail. Surely that has automatic filtering
facilities?
Of course, though I use filters on Zimbra so that I don't need to redefine them
on each of my
machines. Zimbra filters are a bit crappy though and it would be easier for me
to write filters
based on subject. I can
Dnia piątek, 21 grudnia 2012, Radical napisał:
Thanks for the suggestion, Jan. Is there a way to include all of hackage?
Sorry, I don't know any way of doing this.
Janek
___
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
Try this:
http://hackage.haskell.org/trac/ghc/wiki/Repositories
Very nice! WorkingConventions/Repositories still duplicates some information
but that's not a big
problem since neither Repositories nor Repositories/Upstream link to it.
Perhaps it would be good
to give a short explanation
It turns out that running 'perl boot' in symlinked directory (ghc-build) is not
enough. I had to
run 'perl boot' in the original ghc-working dir and now configure succeedes in
ghc-build.
Janek
___
Glasgow-haskell-users mailing list
Dnia wtorek, 18 grudnia 2012, Simon Marlow napisał:
On 18/12/12 10:09, Jan Stolarek wrote:
It turns out that running 'perl boot' in symlinked directory (ghc-build)
is not enough. I had to run 'perl boot' in the original ghc-working dir
and now configure succeedes in ghc-build.
You
So the first page here tells you how to get a single source tree so that
you can build it. The second page tells you how to create a 2-tree
setup for use with GHC's validate; the latter is aimed at people doing
lots of GHC development (which is why it's under WorkingConventions).
I think that
Dnia piątek, 14 grudnia 2012, Ian Lynagh napisał:
I think the main problem is that it's a very broad question. The answer
to how should I get started would be completely different for if you
wanted to implement a type system extension, port GHC to a new platform,
or fix a bug in ghci
All three
OK, so how can we improve it?
First of all I think that materials in the wiki are well organized for people
who already have
some knowledge and only need to learn about particular things they don't yet
know. In this case I
think it is fine to have wiki pages connected between one another so
Dear list,
I have a GHC source tree in ghc-working. I would like to have a separate build
tree in ghc-build,
so I did something like this:
mkdir ghc-build
cd ghc-build
lndir ../ghc-working
Now, I have two different machines. On openSUSE with git 1.8.0 I get something
like this:
make it more useful. It's a wiki.
What else would help? If the answer is X, can anyone help do X?
Thanks
Simon
From: glasgow-haskell-users-boun...@haskell.org
[mailto:glasgow-haskell-users-boun...@haskell.org] On Behalf Of Chris
Nicholls Sent: 13 December 2012 12:00
To: Jan Stolarek
Dear list,
I'm reposting my message from Haskell-cafe here since this seems like a more
appropriate place to
ask this question. I would like to learn about internals of GHC and contribute
to its development
in the future. I read a couple of papers that give a very general overview of
GHC
So to some extent, to work on it probably does require bashing against some
theory for
a while.
I don't mind that, but on the other hand I don't want to get stuck *only* in
theory.
It also depends on the part of the pipeline that you're interested in.
There's quite a difference between,
Sorry! That wasn't what I intended.
I know, but still... :)
I meant more that I have a reasonably, good idea of *how* to work on ghc
That's what I'm trying to figure out right now. GHC build system looks very
complicated and it
seems I'll be spending weeks on understanding it before I can
Dear list,
during many years of Java programming I've been faithful to TDD methology.
Recently I've been
trying to figure out how to do tests in Haskell. Thanks to RWH and help from
great folks at
#haskell I've managed to get on my feet. There is however one issue I wasn't
able to solve.
In
Thanks for replies. CPP approach seems to be what I would like to achieve, but
it looks more like
a hack than a real solution. That said, I like the idea of creating a module
that acts as an
external interface to the library and I I don't mind sacrificing encapsulation
within the package
Hi list,
I have yet another question about folds. Reading here and there I encountered
statements that
foldr is more important than foldl, e.g. in this post on the list:
http://www.haskell.org/pipermail/haskell-cafe/2012-May/101338.html
I want to know are such statements correct and, if so,
74 matches
Mail list logo
