[Haskell-cafe] Message
Would you ever see yourself write a web application like Twitter or Facebook in Haskell? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
Wow, controversial point I guess... I would add: and if yes, what would you use and why? 2011/10/21 Goutam Tmv vo1d_poin...@live.com Would you ever see yourself write a web application like Twitter or Facebook in Haskell? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
This is clearly a job for node.js and the /dev/null data store, since they are so web scale~ Less sarcasm: I think any of the main Haskell web frameworks (Yesod, Happstack, Snap) could scale better than Ruby or PHP, and would use any of those in a heartbeat for such a venture. I'd personally use Yesod. I think data store would be a trickier issue. I'd likely use one of the key/value stores out there, possibly Redis, though I'd really need to do more research to give a real answer. Michael On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com wrote: Wow, controversial point I guess... I would add: and if yes, what would you use and why? 2011/10/21 Goutam Tmv vo1d_poin...@live.com Would you ever see yourself write a web application like Twitter or Facebook in Haskell? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
2011/10/21 Goutam Tmv vo1d_poin...@live.com: Would you ever see yourself write a web application like Twitter or Facebook in Haskell? No. But then, I wouldn't write a web application like either of them in _any_ language. Now, if your question was is Haskell a good language for writing large-scale web applications such as ..., then that's a different story... and one I'm not qualified to answer. -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
I don't think I'm going to write next twitter or facebook but yes, it
is on my TODO list. If such an applications can be written with
languages like PHP then why not. Can't think of any language that is
worse than PHP but still there are lots of web applications written
with that. Even I have written many using PHP.
Why I would use Haskell? To see if it is better option to that problem
than other languages.
I have allready installed Yesod but for now I don't have enough time
to work on this project. After 6 months the situation should be
different.
2011/10/21 Michael Snoyman mich...@snoyman.com:
This is clearly a job for node.js and the /dev/null data store, since
they are so web scale~
Less sarcasm: I think any of the main Haskell web frameworks (Yesod,
Happstack, Snap) could scale better than Ruby or PHP, and would use
any of those in a heartbeat for such a venture. I'd personally use
Yesod.
I think data store would be a trickier issue. I'd likely use one of
the key/value stores out there, possibly Redis, though I'd really need
to do more research to give a real answer.
Michael
On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com wrote:
Wow, controversial point I guess...
I would add: and if yes, what would you use and why?
2011/10/21 Goutam Tmv vo1d_poin...@live.com
Would you ever see yourself write a web application like Twitter or
Facebook in Haskell?
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--
/***/
try {
log.trace(Id= + request.getUser().getId() + accesses +
manager.getPage().getUrl().toString())
} catch(NullPointerException e) {}
/***/
This is a real code, but please make the world a bit better place and
don’t do it, ever.
* http://www.javacodegeeks.com/2011/01/10-tips-proper-application-logging.html *
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[Haskell-cafe] ICFP 2012: Call for workshops and co-located events
CALL FOR WORKSHOP AND CO-LOCATED EVENT PROPOSALS ICFP 2012 17th ACM SIGPLAN International Conference on Functional Programming September 9 - 15, 2012 Copenhagen, Denmark http://icfpconference.org/icfp2012/ The 17th ACM SIGPLAN International Conference on Functional Programming will be held in Copenhagen, Denmark on September 9-15, 2012. ICFP provides a forum for researchers and developers to hear about the latest work on the design, implementations, principles, and uses of functional programming. Proposals are invited for workshops (and other co-located events, such as tutorials) to be affiliated with ICFP 2012 and sponsored by SIGPLAN. These events should be more informal and focused than ICFP itself, include sessions that enable interaction among the attendees, and foster the exchange of new ideas. The preference is for one-day events, but other schedules can also be considered. The workshops are scheduled to occur on September 9 (the day before ICFP) and September 13-15 (the three days after ICFP). -- Submission details Deadline for submission: November 19, 2011 Notification of acceptance: December 17, 2011 Prospective organizers of workshops or other co-located events are invited to submit a completed workshop proposal form in plain text format to the ICFP 2012 workshop co-chairs (Patrik Jansson and Gabriele Keller), via email to icfp12-workshops at cse.unsw.edu.au by November 19, 2011. (For proposals of co-located events other than workshops, please fill in the workshop proposal form and just leave blank any sections that do not apply.) Please note that this is a firm deadline. Organizers will be notified if their event proposal is accepted by December 17, 2011, and if successful, depending on the event, they will be asked to produce a final report after the event has taken place that is suitable for publication in SIGPLAN Notices. The proposal form is available at: http://www.icfpconference.org/icfp2012/icfp12-workshops-form.txt Further information about SIGPLAN sponsorship is available at: http://acm.org/sigplan/sigplan_workshop_proposal.htm -- Selection committee The proposals will be evaluated by a committee comprising the following members of the ICFP 2012 organizing committee, together with the members of the SIGPLAN executive committee. Workshop Co-Chair: Gabriele Keller (University of New South Wales) Workshop Co-Chair: Patrik Jansson (Chalmers University of Technology) General Chair :Peter Thiemann (University of Freiburg) Program Chair: Robby Findler (Northwestern University) -- Further information Any queries should be addressed to the workshop co-chairs (Patrik Jansson and Gabriele Keller), via email to icfp12-workshops at cse.unsw.edu.au ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: vector-bytestring-0.0.0.0
Am 20.10.2011 21:43, schrieb Michael Snoyman: On Wed, Oct 19, 2011 at 9:29 PM, Ketil Maldeke...@malde.org wrote: Michael Snoymanmich...@snoyman.com writes: sense to try and pursue something like what you're suggesting, but I think the default Show (Vector Word8) should be the one most useful, most of the time, and I think the general consensus seems to be the current ByteString instance fits that role. Hm. I think it is slightly weird to display a numeric value (Word8) as a Char. Also, I would prefer a representation making the type explicit (but unlike ByteString, vector seems to add a type annotation.) Would you still support the truncating behavior for 'read' and values above 255? (ByteString has two interfaces, ByteString and .Char8, but as there can be only one Show instance, I see why it works the way it does.) Perhaps the correct semantic approach would be to have: newtype Char8 = Char8 Word8 But I think that will break far too many applications to try to get it would a new Word8 type be better to stay compatible? newtype Word8 = C8 Data.Word.Word8 C. implemented. In an ideal world, I agree with both points: displaying a numeric value as a Char doesn't make sense, and there are definitely issues with the Read instance. However, I still think current behavior is the least of all available evils. Show/Read work properly as a pair and can encode/decode any ByteString, and there's never any presumption that all input to read is valid. Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Type constructor variables no longer injective in GHC 7.2.1?
Hello Cafe,
say we take these standard definitions:
{-# LANGUAGE GADTs, TypeOperators, TypeFamilies, ScopedTypeVariables #-}
data a :=: b where
Refl :: a :=: a
subst :: a :=: b - f a - f b
subst Refl = id
Then this doesn't work (error message at the bottom):
inj1 :: forall f a b. f a :=: f b - a :=: b
inj1 Refl = Refl
But one can still construct it with a trick that Oleg used in the context of
Leibniz equality:
type family Arg fa
type instance Arg (f a) = a
newtype Helper fa fa' = Helper { runHelper :: Arg fa :=: Arg fa' }
inj2 :: forall f a b. f a :=: f b - a :=: b
inj2 p = runHelper (subst p (Helper Refl :: Helper (f a) (f a)))
So, it seems to me that either rejecting inj1 is a bug (or at least an
inconvenience), or GHC is for some reason justified in not assuming type
constructor variables to be injective, and accepting inj2 is a bug. I guess
it's the former, since type constructor variables can't range over type
functions AFAIK.
The error message for inj1 is:
Could not deduce (a ~ b)
from the context (f a ~ f b)
bound by a pattern with constructor
Refl :: forall a. a :=: a,
in an equation for `inj1'
at /tmp/inj.lhs:12:8-11
`a' is a rigid type variable bound by
the type signature for inj1 :: (f a :=: f b) - a :=: b
at /tmp/inj.lhs:12:3
`b' is a rigid type variable bound by
the type signature for inj1 :: (f a :=: f b) - a :=: b
at /tmp/inj.lhs:12:3
Expected type: a :=: b
Actual type: a :=: a
In the expression: Refl
In an equation for `inj1': inj1 Refl = Refl
Cheers,
Daniel
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Re: [Haskell-cafe] Message
Let's look at this from a high, project management level. Twitter ran on...
Ruby initially? Facebook ran on PHP.
Immediately this tells me that programming language choice wasn't a factor
in their success. One succeeded in building a large throughput system with a
slow language, the other succeeded in building a massively popular website
with a bad one.
What hard problems did they have to solve?
Twitter had to deal with scalability, distribution, and massive throughput.
These are hard problems on their own, and are non-trivial even in languages
tailor made to handle them. (Although using Erlang would make things a good
deal easier.)
Facebook is not a technical problem at all. There are interesting challenges
hidden within (ad targeting and friend feed optimization) but they're tiny,
isolated components. Rapid development and prototyping of features help
Facebook, but if the features are easy CRUD stuff it's perfectly cost
effective to hire a pile of PHP developers to do them.
One has problems that are hard regardless of tool choice, the other has no
hard problems at all. No Haskell needed, use whatever language you can
outsource overseas.
With that in mind. Using Haskell gives you an edge, for most problems, even
the ones with poor libraries. If you can get the programmer manpower you
need, it is a clear advantage over your competition.
Your startup may not need that advantage - as Facebook retrospectively
didn't - but you don't know that when just starting out. If Facebook went
deep into user behaviour analysis and newsfeed optimization, the way OkCupid
has with dating, Haskell would suddenly stand out.
If you need every advantage you can get, you use the best tools for the job.
Haskell is one of the best and shiniest - I personally would use Erlang for
any embarrassingly parallel parts of the service and do the rest in Haskell.
On Fri, Oct 21, 2011 at 1:00 AM, Matti Oinas matti.oi...@gmail.com wrote:
I don't think I'm going to write next twitter or facebook but yes, it
is on my TODO list. If such an applications can be written with
languages like PHP then why not. Can't think of any language that is
worse than PHP but still there are lots of web applications written
with that. Even I have written many using PHP.
Why I would use Haskell? To see if it is better option to that problem
than other languages.
I have allready installed Yesod but for now I don't have enough time
to work on this project. After 6 months the situation should be
different.
2011/10/21 Michael Snoyman mich...@snoyman.com:
This is clearly a job for node.js and the /dev/null data store, since
they are so web scale~
Less sarcasm: I think any of the main Haskell web frameworks (Yesod,
Happstack, Snap) could scale better than Ruby or PHP, and would use
any of those in a heartbeat for such a venture. I'd personally use
Yesod.
I think data store would be a trickier issue. I'd likely use one of
the key/value stores out there, possibly Redis, though I'd really need
to do more research to give a real answer.
Michael
On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com
wrote:
Wow, controversial point I guess...
I would add: and if yes, what would you use and why?
2011/10/21 Goutam Tmv vo1d_poin...@live.com
Would you ever see yourself write a web application like Twitter or
Facebook in Haskell?
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--
/***/
try {
log.trace(Id= + request.getUser().getId() + accesses +
manager.getPage().getUrl().toString())
} catch(NullPointerException e) {}
/***/
This is a real code, but please make the world a bit better place and
don’t do it, ever.
*
http://www.javacodegeeks.com/2011/01/10-tips-proper-application-logging.html*
___
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Re: [Haskell-cafe] ANNOUNCE: vector-bytestring-0.0.0.0
On Fri, Oct 21, 2011 at 11:58 AM, Christian Maeder christian.mae...@dfki.de wrote: Am 20.10.2011 21:43, schrieb Michael Snoyman: On Wed, Oct 19, 2011 at 9:29 PM, Ketil Maldeke...@malde.org wrote: Michael Snoymanmich...@snoyman.com writes: sense to try and pursue something like what you're suggesting, but I think the default Show (Vector Word8) should be the one most useful, most of the time, and I think the general consensus seems to be the current ByteString instance fits that role. Hm. I think it is slightly weird to display a numeric value (Word8) as a Char. Also, I would prefer a representation making the type explicit (but unlike ByteString, vector seems to add a type annotation.) Would you still support the truncating behavior for 'read' and values above 255? (ByteString has two interfaces, ByteString and .Char8, but as there can be only one Show instance, I see why it works the way it does.) Perhaps the correct semantic approach would be to have: newtype Char8 = Char8 Word8 But I think that will break far too many applications to try to get it would a new Word8 type be better to stay compatible? newtype Word8 = C8 Data.Word.Word8 I don't think it would really fix much. Any code in the wild right now that refers to Word8 will be referring to Data.Word.Word8. Certainly calling the newtype Word8 will slightly simplify a migration, but (1) it will still require code changes and (2) I'd rather just bite the bullet and make a proper switch. Michael ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] New rss maintainer
On 20 October 2011 21:27, Bas van Dijk v.dijk@gmail.com wrote: Otherwise I could take it over. I probably won't make lots of changes since I'm a bit swamped at the moment. Just updating it to the latest versions. I've moved the repository over to github: https://github.com/basvandijk/rss If nobody steps up as new maintainer I will make a new release this weekend. Cheers, Bas ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
I don't know if you are familiar with it, but perhaps this article can be of interest to you: http://www.paulgraham.com/avg.html And a little historical summary: http://en.wikipedia.org/wiki/Viaweb Best regards, Øystein Kolsrud 2011/10/21 Goutam Tmv vo1d_poin...@live.com Would you ever see yourself write a web application like Twitter or Facebook in Haskell? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Mvh Øystein Kolsrud ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANN: OpenCL 1.0.1.3 package
On 17 October 2011 22:47, Judah Jacobson judah.jacob...@gmail.com wrote: On Mon, Oct 17, 2011 at 2:56 AM, Luis Cabellos cabel...@ifca.unican.es wrote: Other issues to solve, How to compile in hackage server to generate documentation online? opencl.h isn't in the server so I getting errors. In my experience, the nicest way to work around this problem is to just generate the documentation manually and host it somewhere off of Hackage. http://community.haskell.org/admin/ is a decent place to host something like this; you end up with a URL http://projects.haskell.org/yourproject which you can link to from the .cabal file description. That is an acceptable solution. The documentation of hopencl is now hosted at http://projects.haskell.org/hopencl/ Thanks for the pointer. -- Martin Dybdal ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Betfair Opportunity
Hello, I currently work internally at Betfair and we seek Haskell specialists to join our research teams on a permanent basis in London. Please contact me for more details. Thanks, James C Peters Senior Research and Sourcing Consultant Office: +44 (0) 208 834 8513 http://uk.linkedin.com/in/jamescpeters Check out the Betfair Employee Blog: Betfair views | Home of Betfair's Employee Bloghttp://views.betfair.com/ Betfair The #1 Global Online Sports Betting Operator. Please consider the environment before printing this e-mail. Betfair Limited | Winslow Road | Hammersmith Embankment | London | W6 9HP. Registered in England and Wales under company number 5140986. This email (which includes any attachment and any subsequent reply) is sent for and on behalf of one or more operating entities in the Betfair Group, details of which are available herehttp://corporate.betfair.com/about-us.aspx. The information in this e-mail is confidential and may contain legal advice that is subject to legal privilege. As such it is intended only for the named recipient(s). This e-mail may not be disclosed or used by any person other than the addressee, nor may it be copied in any way. If you are not a named recipient please notify the sender immediately and delete any copies of this email. Any unauthorised copying, disclosure or distribution of the material in this e-mail is strictly forbidden. Any view or opinions presented are solely those of the author and do not necessarily represent those of the Betfair Group. Betfair(r) and the BETFAIR LOGO are registered trade marks of The Sporting Exchange Limited. In order to protect our email recipients, Betfair Group use SkyScan from MessageLabs to scan all Incoming and Outgoing mail for viruses. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Functional Programmer required for a Greenfield project in a software house in London.
Ideally from a high performance computing, real-time systems background (OO experience, either java or c++). Get in touch for more details. Oliver Horncastle Madison Maclean Email: oliver.horncas...@madisonmaclean.commailto:oliver.horncas...@madisonmaclean.com Direct Line: 020 30 30 50 53 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Trying to install hpodder on OS X Lion
I'd really like to get hpodder installed on OS X Lion, I can't find it
packaged anywhere (macports, homebrew...) Has anyone got it working?
I have the haskell platform installed from the pkg file from haskell.org:
http://hackage.haskell.org/platform/mac.html
So I tried `cabal install hpodder` but it failed. First I get a lot of
warnings like:
ld: warning: text reloc in _cZh_str to _stg_ap_pp_fast
ld: warning: text reloc in _cZh_str to _stg_ap_p_fast
ld: warning: text reloc in _cZh_str to _stg_ap__fast
ld: warning: text reloc in _cZh_str to _stg_ap_pppv_fast
ld: warning: text reloc in _cZh_str to _stg_ap_ppp_fast
ld: warning: text reloc in _cZh_str to _stg_ap_ppv_fast
ld: warning: text reloc in _cZh_str to _stg_ap_pp_fast
ld: warning: text reloc in _cZh_str to _stg_ap_pv_fast
ld: warning: text reloc in _cZh_str to _stg_ap_p_fast
ld: warning: text reloc in _cZh_str to _stg_ap_n_fast
ld: warning: text reloc in _cZh_str to _stg_ap_l_fast
ld: warning: text reloc in _cZh_str to _stg_ap_d_fast
ld: warning: text reloc in _cZh_str to _stg_ap_f_fast
ld: warning: text reloc in _cZh_str to _stg_ap_v_fast
ld: warning: text reloc in _cZh_str to _stg_ap_pp_info
I get each of those warnings many times in a row. There are some other
warning when compiling things as well. Then I eventually get:
cabal: Error: some packages failed to install:
hpodder-1.1.5 failed during the building phase. The exception was:
ExitFailure 1
Here's the error from the compiler before that:
Commands/SetStatus.hs:59:33:
Ambiguous type variable `e0' in the constraint:
(E.Exception e0) arising from a use of `E.catch'
Probable fix: add a type signature that fixes these type variable(s)
In the expression:
E.catch
(E.evaluate (read x))
(\ _
- fail
$ Invalid status supplied; use one of: ++ possibleStatuses)
In a case alternative:
Just x
- E.catch
(E.evaluate (read x))
(\ _
- fail
$ Invalid status supplied; use one of: ++
possibleStatuses)
In a stmt of a 'do' expression:
newstatus - case lookup status args of {
Just x
- E.catch
(E.evaluate (read x))
(\ _
- fail
$ Invalid status supplied; use
one of: ++ possibleStatuses)
Nothing
- fail
setstatus: --status required; see
hpodder setstatus --help }
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Re: [Haskell-cafe] Message
That's interesting, have you ever worked on interfacing Erlang with Haskell?
BTW, Twitter switched to Scala, so obviously their initial choice of Ruby
end up invalidated.
2011/10/21 Alex Kropivny alex.kropi...@gmail.com
Let's look at this from a high, project management level. Twitter ran on...
Ruby initially? Facebook ran on PHP.
Immediately this tells me that programming language choice wasn't a factor
in their success. One succeeded in building a large throughput system with a
slow language, the other succeeded in building a massively popular website
with a bad one.
What hard problems did they have to solve?
Twitter had to deal with scalability, distribution, and massive throughput.
These are hard problems on their own, and are non-trivial even in languages
tailor made to handle them. (Although using Erlang would make things a good
deal easier.)
Facebook is not a technical problem at all. There are interesting
challenges hidden within (ad targeting and friend feed optimization) but
they're tiny, isolated components. Rapid development and prototyping of
features help Facebook, but if the features are easy CRUD stuff it's
perfectly cost effective to hire a pile of PHP developers to do them.
One has problems that are hard regardless of tool choice, the other has no
hard problems at all. No Haskell needed, use whatever language you can
outsource overseas.
With that in mind. Using Haskell gives you an edge, for most problems, even
the ones with poor libraries. If you can get the programmer manpower you
need, it is a clear advantage over your competition.
Your startup may not need that advantage - as Facebook retrospectively
didn't - but you don't know that when just starting out. If Facebook went
deep into user behaviour analysis and newsfeed optimization, the way OkCupid
has with dating, Haskell would suddenly stand out.
If you need every advantage you can get, you use the best tools for the
job. Haskell is one of the best and shiniest - I personally would use Erlang
for any embarrassingly parallel parts of the service and do the rest in
Haskell.
On Fri, Oct 21, 2011 at 1:00 AM, Matti Oinas matti.oi...@gmail.comwrote:
I don't think I'm going to write next twitter or facebook but yes, it
is on my TODO list. If such an applications can be written with
languages like PHP then why not. Can't think of any language that is
worse than PHP but still there are lots of web applications written
with that. Even I have written many using PHP.
Why I would use Haskell? To see if it is better option to that problem
than other languages.
I have allready installed Yesod but for now I don't have enough time
to work on this project. After 6 months the situation should be
different.
2011/10/21 Michael Snoyman mich...@snoyman.com:
This is clearly a job for node.js and the /dev/null data store, since
they are so web scale~
Less sarcasm: I think any of the main Haskell web frameworks (Yesod,
Happstack, Snap) could scale better than Ruby or PHP, and would use
any of those in a heartbeat for such a venture. I'd personally use
Yesod.
I think data store would be a trickier issue. I'd likely use one of
the key/value stores out there, possibly Redis, though I'd really need
to do more research to give a real answer.
Michael
On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com
wrote:
Wow, controversial point I guess...
I would add: and if yes, what would you use and why?
2011/10/21 Goutam Tmv vo1d_poin...@live.com
Would you ever see yourself write a web application like Twitter or
Facebook in Haskell?
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--
/***/
try {
log.trace(Id= + request.getUser().getId() + accesses +
manager.getPage().getUrl().toString())
} catch(NullPointerException e) {}
/***/
This is a real code, but please make the world a bit better place and
don’t do it, ever.
*
http://www.javacodegeeks.com/2011/01/10-tips-proper-application-logging.html*
___
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Re: [Haskell-cafe] Trying to install hpodder on OS X Lion
On Fri, Oct 21, 2011 at 9:32 AM, seanh snh...@gmail.com wrote: I'd really like to get hpodder installed on OS X Lion, I can't find it packaged anywhere (macports, homebrew...) Has anyone got it working? I have the haskell platform installed from the pkg file from haskell.org: http://hackage.haskell.org/platform/mac.html So I tried `cabal install hpodder` but it failed. First I get a lot of warnings like: SNIP I don't know much about these, but they are unrelated to the error bellow. Here's the error from the compiler before that: Commands/SetStatus.hs:59:33: Ambiguous type variable `e0' in the constraint: (E.Exception e0) arising from a use of `E.catch' Probable fix: add a type signature that fixes these type variable(s) SNIP The exceptions API changed in GHC 6.10, and the 'hpodder' package on hackage hasn't been updated to accommodate those changes. It looks like the version up on github should no longer have this error: https://github.com/jgoerzen/hpodder It may have other errors, though - I haven't tried it :-) Antoine ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Trying to install hpodder on OS X Lion
On 21 October 2011 17:20, Antoine Latter aslat...@gmail.com wrote: The exceptions API changed in GHC 6.10, and the 'hpodder' package on hackage hasn't been updated to accommodate those changes. It looks like the version up on github should no longer have this error: https://github.com/jgoerzen/hpodder It may have other errors, though - I haven't tried it :-) Thanks. Any advice on how to install it from source? I'm not familiar with haskell stuff, and the instructions are missing: https://github.com/jgoerzen/hpodder/blob/master/INSTALL ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] New rss maintainer
On 10/20/2011 08:27 PM, Bas van Dijk wrote: Hello, I've a small patch[1] that updates the rss package to the latest versions of its dependencies. (I'm trying to get the new hackage-server to build on ghc-7.2.1) However Bjorn Bringert told me he's no longer maintaining the package. He asked me to ask you if there's already a new maintainer. If not, does any one want to take over the package? Jeremy, maybe you? Otherwise I could take it over. I probably won't make lots of changes since I'm a bit swamped at the moment. Just updating it to the latest versions. Perhaps, unless someone step up, it would be nice to move packages that have no maintainer anymore into a github organisation (haskell-janitors ?), where each package could have many owners and it's easy and simple to add/remove push rights there. That could also be an obvious place to look, for newcomers, to get involved. -- Vincent ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Trying to install hpodder on OS X Lion
On Fri, Oct 21, 2011 at 10:33 AM, seanh snh...@gmail.com wrote: On 21 October 2011 17:20, Antoine Latter aslat...@gmail.com wrote: The exceptions API changed in GHC 6.10, and the 'hpodder' package on hackage hasn't been updated to accommodate those changes. It looks like the version up on github should no longer have this error: https://github.com/jgoerzen/hpodder It may have other errors, though - I haven't tried it :-) Thanks. Any advice on how to install it from source? I'm not familiar with haskell stuff, and the instructions are missing: https://github.com/jgoerzen/hpodder/blob/master/INSTALL The standard way is to type cabal install in a directory which contains a '.cabal' file. Antoine ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Data.Vector.Mutable.mapM
Hi, Am Donnerstag, den 20.10.2011, 23:10 +0200 schrieb Ertugrul Soeylemez: In general you should try to work with immutable vectors as much as possible. Done properly you shouldn't lose much performance that way. However, sometimes an operation is just much easier to express and faster with the MVector interface. In these cases you can escape to the mutable interface using 'create', 'modify', 'thaw' and 'freeze'. Don't forget that you lose fusion that way, though. In other words: Don't use MVector exclusively. Use it only when you really need it. that was my plan, although it is a bit more complicated as I have a immutable vector of immutable boxed vectors that I’d like to modify destructively. Currently, I have lots of V.map and V.filter... The code is here, and should perform constant propagation in a SAT-instance: http://git.nomeata.de/?p=sat-britney.git;a=blob;f=Picosat.hs;h=910e530a0aa546b7b8b9e9e995c0885b0a6e1371;hb=HEAD#l312 Greetings, Joachim -- Joachim nomeata Breitner m...@joachim-breitner.de | nome...@debian.org | GPG: 0x4743206C xmpp: nome...@joachim-breitner.de | http://www.joachim-breitner.de/ signature.asc Description: This is a digitally signed message part ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
On Fri, Oct 21, 2011 at 8:02 AM, Yves Parès limestr...@gmail.com wrote: That's interesting, have you ever worked on interfacing Erlang with Haskell? I have interfaced Erlang and Haskell... And delivered it as a product. I just came up with a dead-simple text based communication syntax from Erlang to Haskell that was very easily testable. It allowed for complete isolation of components and them to be developed and debugged in parallel. The Haskell code was an Erlang pipe driver, which, in turn was connected to a C program to drive a polling interface, controlled by Haskell with the fancy IO done in C. All of this was on a relatively small linux appliance. I'm pretty proud of that little system. It was quickly done, and I was able to mock out various pieces of it very quickly as well. When the hardware it was meant to control finally arrived I think I only spent a few extra hours turning the screws to make it work for real and then we discovered wiring problems :-) BTW, Twitter switched to Scala, so obviously their initial choice of Ruby end up invalidated. I believe they have Java, Clojure and Scala actually. I know of a guy doing a start up using only Go, and that language is not even fully released yet. They're most definitely using Clojure in their Storm realtime event processing framework anyway, and it's freely available. Other than finding people who can come work for you writing good Haskell code, I don't see any reason to avoid doing a startup using that language as a code base. The Haskell Platform makes things a little nicer, but needs to have more regular releases. Go comes with a lot of batteries already making it slightly more attractive. Dave 2011/10/21 Alex Kropivny alex.kropi...@gmail.com Let's look at this from a high, project management level. Twitter ran on... Ruby initially? Facebook ran on PHP. Immediately this tells me that programming language choice wasn't a factor in their success. One succeeded in building a large throughput system with a slow language, the other succeeded in building a massively popular website with a bad one. What hard problems did they have to solve? Twitter had to deal with scalability, distribution, and massive throughput. These are hard problems on their own, and are non-trivial even in languages tailor made to handle them. (Although using Erlang would make things a good deal easier.) Facebook is not a technical problem at all. There are interesting challenges hidden within (ad targeting and friend feed optimization) but they're tiny, isolated components. Rapid development and prototyping of features help Facebook, but if the features are easy CRUD stuff it's perfectly cost effective to hire a pile of PHP developers to do them. One has problems that are hard regardless of tool choice, the other has no hard problems at all. No Haskell needed, use whatever language you can outsource overseas. With that in mind. Using Haskell gives you an edge, for most problems, even the ones with poor libraries. If you can get the programmer manpower you need, it is a clear advantage over your competition. Your startup may not need that advantage - as Facebook retrospectively didn't - but you don't know that when just starting out. If Facebook went deep into user behaviour analysis and newsfeed optimization, the way OkCupid has with dating, Haskell would suddenly stand out. If you need every advantage you can get, you use the best tools for the job. Haskell is one of the best and shiniest - I personally would use Erlang for any embarrassingly parallel parts of the service and do the rest in Haskell. On Fri, Oct 21, 2011 at 1:00 AM, Matti Oinas matti.oi...@gmail.comwrote: I don't think I'm going to write next twitter or facebook but yes, it is on my TODO list. If such an applications can be written with languages like PHP then why not. Can't think of any language that is worse than PHP but still there are lots of web applications written with that. Even I have written many using PHP. Why I would use Haskell? To see if it is better option to that problem than other languages. I have allready installed Yesod but for now I don't have enough time to work on this project. After 6 months the situation should be different. 2011/10/21 Michael Snoyman mich...@snoyman.com: This is clearly a job for node.js and the /dev/null data store, since they are so web scale~ Less sarcasm: I think any of the main Haskell web frameworks (Yesod, Happstack, Snap) could scale better than Ruby or PHP, and would use any of those in a heartbeat for such a venture. I'd personally use Yesod. I think data store would be a trickier issue. I'd likely use one of the key/value stores out there, possibly Redis, though I'd really need to do more research to give a real answer. Michael On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com wrote: Wow, controversial point I guess...
Re: [Haskell-cafe] Message
On 11-10-21 03:59 AM, Ivan Lazar Miljenovic wrote: 2011/10/21 Goutam Tmvvo1d_poin...@live.com: Would you ever see yourself write a web application like Twitter or Facebook in Haskell? No. But then, I wouldn't write a web application like either of them in _any_ language. +1 The world does not need another Twitter, another Facebook, another Reddit, another graphics engine, another database system, or another operating system. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
Non snarky question - what does it need? -deech On Fri, Oct 21, 2011 at 12:51 PM, Albert Y. C. Lai tre...@vex.net wrote: On 11-10-21 03:59 AM, Ivan Lazar Miljenovic wrote: 2011/10/21 Goutam Tmvvo1d_poin...@live.com: Would you ever see yourself write a web application like Twitter or Facebook in Haskell? No. But then, I wouldn't write a web application like either of them in _any_ language. +1 The world does not need another Twitter, another Facebook, another Reddit, another graphics engine, another database system, or another operating system. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
Ok, I'll bite: what's it need? - Tom / amindfv On Fri, Oct 21, 2011 at 1:51 PM, Albert Y. C. Lai tre...@vex.net wrote: On 11-10-21 03:59 AM, Ivan Lazar Miljenovic wrote: 2011/10/21 Goutam Tmvvo1d_poin...@live.com: Would you ever see yourself write a web application like Twitter or Facebook in Haskell? No. But then, I wouldn't write a web application like either of them in _any_ language. +1 The world does not need another Twitter, another Facebook, another Reddit, another graphics engine, another database system, or another operating system. __**_ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/**mailman/listinfo/haskell-cafehttp://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
There's no technical reason why not; Twitter is written in Scala and Facebook's chat system in Erlang. Would I see *myself* working at one of these companies? Not likely. Cheers, G -- -Original Message- From: Goutam Tmv vo1d_poin...@live.com Sender: haskell-cafe-boun...@haskell.org Date: Fri, 21 Oct 2011 15:37:42 To: haskell-cafe@haskell.org Subject: [Haskell-cafe] Message ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
On 11-10-21 01:57 PM, aditya siram wrote: Non snarky question - what does it need? On 11-10-21 01:58 PM, Tom Murphy wrote: Ok, I'll bite: what's it need? Thank you for asking. The world needs another tutorial on lazy evaluation for Haskell. There are currently only 0.5, and it is written by me. While I will complete it to 1, the world needs 3. (Generally, the world needs 3 tutorials for every subject.) http://www.vex.net/~trebla/haskell/lazy.xhtml The world needs programmers to accept and take seriously Greg Wilson's extensible programming, and stop laughing it off as lolwut wysiwyg msword for programming, and start implementing it. http://third-bit.com/blog/archives/4302.html The world needs more applied formal methods. http://vstte.ethz.ch/pdfs/vstte-hoare-misra.pdf ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Message
Yes I did, in detail. There are two trivial solutions I like: 1. The BERT library (http://bert-rpc.org/) uses Erlang terms for the protocol, and has straightforward mappings to Haskell equivalents. - Pros: trivial on both sides, Erlang terms are really good primitives to build a protocol from - Cons: Erlang likes using large (5 to 10 size) tuples and Haskell doesn't, protocol needs to take that into account 2. JSON over HTTP, Erlang's the server Haskell's the client. - Pros: discoverable, flexible, readable, language agnostic. - Cons: I don't really know how to use Haskell JSON libraries + which ones are good, and good REST API design can be tricky. For higher performance there are other options, but these are the ones I like most. I used 1 to decent effect when using QuickCheck to test an Erlang system. On Fri, Oct 21, 2011 at 8:02 AM, Yves Parès limestr...@gmail.com wrote: That's interesting, have you ever worked on interfacing Erlang with Haskell? BTW, Twitter switched to Scala, so obviously their initial choice of Ruby end up invalidated. 2011/10/21 Alex Kropivny alex.kropi...@gmail.com Let's look at this from a high, project management level. Twitter ran on... Ruby initially? Facebook ran on PHP. Immediately this tells me that programming language choice wasn't a factor in their success. One succeeded in building a large throughput system with a slow language, the other succeeded in building a massively popular website with a bad one. What hard problems did they have to solve? Twitter had to deal with scalability, distribution, and massive throughput. These are hard problems on their own, and are non-trivial even in languages tailor made to handle them. (Although using Erlang would make things a good deal easier.) Facebook is not a technical problem at all. There are interesting challenges hidden within (ad targeting and friend feed optimization) but they're tiny, isolated components. Rapid development and prototyping of features help Facebook, but if the features are easy CRUD stuff it's perfectly cost effective to hire a pile of PHP developers to do them. One has problems that are hard regardless of tool choice, the other has no hard problems at all. No Haskell needed, use whatever language you can outsource overseas. With that in mind. Using Haskell gives you an edge, for most problems, even the ones with poor libraries. If you can get the programmer manpower you need, it is a clear advantage over your competition. Your startup may not need that advantage - as Facebook retrospectively didn't - but you don't know that when just starting out. If Facebook went deep into user behaviour analysis and newsfeed optimization, the way OkCupid has with dating, Haskell would suddenly stand out. If you need every advantage you can get, you use the best tools for the job. Haskell is one of the best and shiniest - I personally would use Erlang for any embarrassingly parallel parts of the service and do the rest in Haskell. On Fri, Oct 21, 2011 at 1:00 AM, Matti Oinas matti.oi...@gmail.comwrote: I don't think I'm going to write next twitter or facebook but yes, it is on my TODO list. If such an applications can be written with languages like PHP then why not. Can't think of any language that is worse than PHP but still there are lots of web applications written with that. Even I have written many using PHP. Why I would use Haskell? To see if it is better option to that problem than other languages. I have allready installed Yesod but for now I don't have enough time to work on this project. After 6 months the situation should be different. 2011/10/21 Michael Snoyman mich...@snoyman.com: This is clearly a job for node.js and the /dev/null data store, since they are so web scale~ Less sarcasm: I think any of the main Haskell web frameworks (Yesod, Happstack, Snap) could scale better than Ruby or PHP, and would use any of those in a heartbeat for such a venture. I'd personally use Yesod. I think data store would be a trickier issue. I'd likely use one of the key/value stores out there, possibly Redis, though I'd really need to do more research to give a real answer. Michael On Fri, Oct 21, 2011 at 9:42 AM, Yves Parès limestr...@gmail.com wrote: Wow, controversial point I guess... I would add: and if yes, what would you use and why? 2011/10/21 Goutam Tmv vo1d_poin...@live.com Would you ever see yourself write a web application like Twitter or Facebook in Haskell? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org
Re: [Haskell-cafe] ANN: OpenCL 1.0.1.3 package
On Thu, Oct 13, 2011 at 12:34 PM, Martin Dybdal dyb...@dybber.dk wrote: On 3 October 2011 12:56, Luis Cabellos cabel...@ifca.unican.es wrote: Hello, all. I want to show you the OpenCL package. I have done this using Jeff Heard OpenCLRaw package, but I create a new one due the lack of updates of the former. # Where to get it * Hackage page (http://hackage.haskell.org/package/OpenCL) * Repository (https://github.com/zhensydow/opencl) * Bugs (https://github.com/zhensydow/opencl/issues) * Examples (https://github.com/zhensydow/opencl/tree/master/examples). # Things: * I write it's high-level binding to OpenCL libraries, but only because I added more types to hide most of the alloc/free of the API, and hide the enums using c2hs enums. * The worst problem of the OpenCLRaw is the bad types it use, I learn to fix 32/64 bits issues with c2hs, and test it on linux machines. * Tested on Linux + NVidia only. * Jason Dagit is helping with Windows, OSX testing in own fork, also the call-conv fork in github has changes to work on Windows Please, Consider it's on experimental status but it works, I need lots of feedbacks for detect posible errors, Thanks, Hi everyone I just found this thread today, as I don't read Haskell-cafe that often (too bad, I know). I have been working on a set of OpenCL bindings for the last months myself, which I'm using to implement an OpenCL backend to the Data.Array.Accelerate library. The work is done at the HIPERFIT research center, Uni. Copenhagen. My bindings are even further from the naming conventions of the OpenCL library, but I really can't see the problem with that. People which are used to programming OpenCL from C/C++ might have to learn how the naming conventions of the Haskell library are, but they only need to do this once. I think it's important to distinguish between being a new API and being a faithful binding to an established API. In reality it ends up as a continuum because an exact one to one mapping is not possible between idiomatic C and idiomatic Haskell. If someone is renaming things or changing the API when not strictly necessary then I would say person is making a new API based on the the old API. My desire is to have a binding which is faithful to the C API and then letting people build new abstractions on top of that. When the mapping between the old and the new naming conventions are learned, they will benefit from having a more clean interface for all future times. (No Haskell hacker should have a problem with a steep learning curve.) I have to disagree here, based largely on my experience with learning other Haskell bindings (for example OpenGL, which I knew from C). If I were to twist your words I could use this to say that we should make Haskell hard to learn. I doubt that's what you meant but it seems dangerously close to me. Probably we have very different goals. You want to make a nice OpenCL-based API for parallel programming and I want a binding that matches the OpenCL api very closely, but not to the point of using Ptr () in many places. It is somewhat troubling that we now have five different interfaces to OpenCL (that I know of), and I think we should join efforts and make one library that is as stable as possible. The five libraries are: I agree that having so many implementations of the binding is odd. I wonder if it's because they cater to different needs. In the case of OpenCLRaw we could reasonably remove it from the list because it's unmaintained and incomplete. And yes, it would be nice to merge efforts. Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] What is the etiquette for posting to multiple forums?
I know it's bad form to post the same question to multiple mailing lists. But what about say, the beginner's mailing list and stackoverflow.com? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] What is the etiquette for posting to multiple forums?
2011/10/21 Michael Litchard mich...@schmong.org: I know it's bad form to post the same question to multiple mailing lists. But what about say, the beginner's mailing list and stackoverflow.com? Hi, Nothing is carved in stone, use your judgment. It shouldn't be done systematically but from time to time, it is interesting to point people to existing discussion (e.g. blog post, reddit thread, or SO answers). I believe currently SO and beginners' mailing list have not exactly the same audience so if you don't get the answer you're after in one place, trying later in the other is fine. Cheers, Thu ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Haddock fails on ConfigFile, but why?
Would love to get some help on making Haddock accept ConfigFile[1]. The error message is about as far from helpful as you can get ;) dist/build/tmp-15743/src/Data/ConfigFile/Monadic.hs:34:1: parse error on input `import' The author is informed but is as confused as me, it seems[2]. /M [1] http://hackage.haskell.org/package/ConfigFile [2] https://github.com/jgoerzen/configfile/issues/4 -- Magnus Therning OpenPGP: 0xAB4DFBA4 email: mag...@therning.org jabber: mag...@therning.org twitter: magthe http://therning.org/magnus Most software today is very much like an Egyptian pyramid with millions of bricks piled on top of each other, with no structural integrity, but just done by brute force and thousands of slaves. -- Alan Kay pgp555AtE4RXi.pgp Description: PGP signature ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haddock fails on ConfigFile, but why?
On 22 October 2011 08:49, Magnus Therning mag...@therning.org wrote: Would love to get some help on making Haddock accept ConfigFile[1]. The error message is about as far from helpful as you can get ;) dist/build/tmp-15743/src/Data/ConfigFile/Monadic.hs:34:1: parse error on input `import' The author is informed but is as confused as me, it seems[2]. Have you tried removing bits from that comment that precedes that line to try and track down where it's going wrong? -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haddock fails on ConfigFile, but why?
On Friday 21 October 2011, 23:49:45, Magnus Therning wrote: Would love to get some help on making Haddock accept ConfigFile[1]. The error message is about as far from helpful as you can get ;) dist/build/tmp-15743/src/Data/ConfigFile/Monadic.hs:34:1: parse error on input `import' The author is informed but is as confused as me, it seems[2]. /M [1] http://hackage.haskell.org/package/ConfigFile [2] https://github.com/jgoerzen/configfile/issues/4 It may be that haddock requires the comments to be indented, or at least the bird-tracke code blocks. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haddock fails on ConfigFile, but why?
On Friday 21 October 2011, 23:49:45, Magnus Therning wrote: Would love to get some help on making Haddock accept ConfigFile[1]. The error message is about as far from helpful as you can get ;) dist/build/tmp-15743/src/Data/ConfigFile/Monadic.hs:34:1: parse error on input `import' The author is informed but is as confused as me, it seems[2]. Okay, a bit of experimentation showed that the imports must come before the haddock comment section $overview. Whether it's a haddock bug, or a feature request for haddock to handle such situations, I don't know. Cheers, Daniel ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] runStateT execution times measurement baffling
On 11-10-20 01:38 PM, thomas burt wrote: I've been trying to measure execution time for some code I'm running with the StateT monad transformer. I have a function f :: StateT MyState IO a Now, I measure the time it takes to run an invocation of this function from beginning to end, i.e. f = do t0 - getCurrentTime stuffToDo t1 - getCurrentTime liftIO $ putStrLn (show $ diffUTCTime t1 t0) And also measure like this: g :: IO g = do t0 - getCurrentTime (val,newState) - runStateT f initialState t1 - getCurrentTime putStrLn $ outside: ++ (show $ diffUTCTime t1 t0) Where can I find stuffToDo? How do you get away with getCurrentTime (as opposed to liftIO getCurrentTime) inside f? Does not type-check. How much should I trust this code? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
