[Haskell-cafe] how to change a process name
Hello, I would like to know how to change a process name in Haskell. When we are programming in C, we can change it by overriding argv on Unix. But I cannot find the same way to do in Haskell. Can anyone suggest how in Haskell? I'm not talking about the result of System.Environment.getProgName but talking about the process name which we can see by the ps command. Thanks. --Kazu ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to ensure code executes in the context of a specific OS thread?
On 06/07/2011 21:11, David Barbour wrote: On Wed, Jul 6, 2011 at 12:52 PM, Simon Marlow marlo...@gmail.com mailto:marlo...@gmail.com wrote: I think the real issue is that GHC has a different behavior than GHCi, and I think this causes a lot of difficulties for people working on GUI and other FFI integration. Well, GHCi has no main, so it doesn't seem surprising (to me) that it's different. If we start GHCi then run the function called 'main', we should ideally get the same behavior as building with GHC then executing the process. Variations make exploratory programming with GHCi very difficult, especially with concurrent haskell. That's a fair point. However, if -fno-ghci-sandbox doesn't have any drawbacks we could just make it the default. That sounds good, too. I think it worth looking up what the drawbacks will be. It might be an acceptable trade even if there are minor drawbacks. I would imagine the main benefit of the sandbox is ability to interrupt a task - i.e. job control from the GHCi shell. Interruption is not affected, as far as I'm aware. Cheers, Simon ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to ensure code executes in the context of a specific OS thread?
On 06/07/2011 21:19, Jason Dagit wrote: On Wed, Jul 6, 2011 at 12:52 PM, Simon Marlowmarlo...@gmail.com wrote: On 06/07/11 17:14, David Barbour wrote: On Wed, Jul 6, 2011 at 8:09 AM, Simon Marlowmarlo...@gmail.com mailto:marlo...@gmail.com wrote: On 06/07/2011 15:42, Jason Dagit wrote: How can I make sure my library works from GHC (with arbitrary user threads) and from GHCI? Right, but usually the way this is implemented is with some cooperation from the main thread. [...] So you can't just do this from a library - the main thread has to be in on the game. I suppose you might wonder whether the GHC RTS could implement runInMainThread by preempting the main thread and running some different code on it. [...] I think the real issue is that GHC has a different behavior than GHCi, and I think this causes a lot of difficulties for people working on GUI and other FFI integration. Perhaps it would be possible to reverse the default roles of threads in GHCi: the main thread run user commands, and a second bound thread will process user interrupts and such. Well, GHCi has no main, so it doesn't seem surprising (to me) that it's different. However, if -fno-ghci-sandbox doesn't have any drawbacks we could just make it the default. I don't actually remember why we run each statement in a new thread, I think it just seemed like a prudent thing to do. +1 for this change. I'm not sure how we would know if there are drawbacks. Now that I think about it, the original reason may have been that if the computation grows a large stack, having it in a separate thread means GHCi can recover the memory. However we have been able to recover stack memory for some time now, so that is no longer an issue. Cheers, Simon ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] NLP libraries and tools?
It's actually a shame we're discussing this on -cafe and not on -nlp. Then again, maybe it's going to prompt somebody to join -nlp, and I'm gonna CC it there, because some folks over there might be interested, but not read -cafe. On Wed, Jul 06, 2011 at 07:22:41PM -0700, wren ng thornton wrote: On 7/6/11 5:58 PM, Aleksandar Dimitrov wrote: On Wed, Jul 06, 2011 at 09:32:27AM -0700, wren ng thornton wrote: On 7/6/11 9:27 AM, Dmitri O.Kondratiev wrote: Hi, Continuing my search of Haskell NLP tools and libs, I wonder if the following Haskell libraries exist (googling them does not help): 1) End of Sentence (EOS) Detection. Break text into a collection of meaningful sentences. Depending on how you mean, this is either fairly trivial (for English) or an ill-defined problem. For things like determining whether the . character is intended as a full stop vs part of an abbreviation; that's trivial. I disagree. It's not exactly trivial in the sense that it is solved. It is trivial in the sense that, usually, one would use a list of know abbreviations and just compare. This, however, just says that the most common approach is trivial, not that the problem is. Perhaps. I recall David Yarowsky suggesting it was considered solved (for English, as I qualified earlier). The solution I use is just to look at a window around the point and run a standard feature-based machine learning algorithm over it[1]. Memorizing known abbreviations is actually quite fragile, for reasons you mention. This approach will give you accuracy in the high 90s, though I forget the exact numbers. That is indeed one of the best ways to do it (for Indo-European languages, anyway.) When you mentioned Arabic for producing sentences that go on for ages — you don't really need to go that far. I have had the doubtful pleasure of reading Kant and Hegel in their original versions. In German, it is sometimes still considered good style to write huge sentences. I once made it a point, just to stick it to a Kant-loving-person, to produce a sentence that spanned 2 whole pages (A4.) It wasn't even difficult. I sometimes think that we should just adopt a similar notion of span, like rhetorical structure theorists do. In that case, you're not segmenting sentences, but discourse atoms — those are even more ill-defined, however. But the problem is that what constitutes an appropriate solution for computational needs is still very ill-defined. Well, yes, and, well, no. Tokens are ill-defined. There's no good consensus on how you should parse tokens (i.e., is in spite of one token or three?) either, and so you just pick one that works for you. Same for sentence boundaries: they're sometimes also ill-defined, but who says you need to define it well? Maybe there's just a purpose-driven definition? — that people can agree on, anyways. My purpose is either tagging, or parsing, or NE-detection, or computational semantics… In all cases, I'm choosing the definition my tools can use. Not because that's correct, but I don't really need it to be, no? I'm very much a works for me person in these matters. Mostly because I'm tired of linguists fighting each other over trivial matters. Give me something I can work with already! Regards, Aleks signature.asc Description: Digital signature ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Web Framework to Show Experimental Data
Hi! I am looking for the Haskell libraries to quickly create some Web Framework to Show Experimental Data. Please share your experience and ideas. What tools would you chose for such a framework: == Architecture There are several unsynchronized processes: 1) Finder - demon that periodically searches and collects JSON data from the Web and stores this data in some sort of Archive (DB). 2) Processor - demon that periodically process new data from Archive collected by Finder and stores results of its work in the same Archive. 3) Web application that shows processed data in a browser. == General Requirements *** Main requirement - simplicity and high speed of development *** - Max Data storage capacity - 10 Mb - Max number of Web users - 50 - Web UI shows what Archive has at the moment of user request. == Web UI Requirements - Multi-page view of long data sets (some sort of scrolling) - Simple graphs and charts (desirable) == Questions 1) What to use for the Archive? Though input data is in JSON format, data generated from it is binary vectors. Not sure that CouchDB is a good choice in this case. What simple (Haskell lib + DB) combination one may advise that support concurrent read / write access with simple locking (don't need full transactional support)? 2) Web framework? Don't need AJAX, just basic stuff but simple and easy to code forms? Thanks! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Web Framework to Show Experimental Data
On Thu, 2011-07-07 at 13:21 +0400, Dmitri O.Kondratiev wrote: 1) What to use for the Archive? Though input data is in JSON format, data generated from it is binary vectors. Not sure that CouchDB is a good choice in this case. What simple (Haskell lib + DB) combination one may advise that support concurrent read / write access with simple locking (don't need full transactional support)? I think this might be an excellent place to use Lemmih's acid-state package. If I read you correctly, you basically want to store a small enough amount of data that it's not a concern that it will need to reside in memory, and it's fairly regular so there won't be a lot of value in ad hoc queries? If this is the case, then acid-state will let you store it in Haskell data types, and with a bit of Template Haskell, you can access it in a persistent way. 2) Web framework? Don't need AJAX, just basic stuff but simple and easy to code forms? Well, I like Snap enough that I became a core developer for the project, but this seems like a place it's particularly well suited. If you just want something really simple and clean and easy to use, Snap is that thing. Snap itself is very lightweight, but if you want some kind of automated form support, then there is a snap backend for digestive-functors. That's a little complex for my taste, but it is one way to do composing of forms by sticking together form handlers, validators, and the like. Personally, I'm a fan of just using getParam to retrieve the data and writing Haskell code to do what you want. -- Chris ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] CFP: PADL'12 - Practical Aspects of Declarative Languages 2012
[Apologies if you receive multiple copies.] Call for Papers === 14th International Symposium on Practical Aspects of Declarative Languages (PADL 2012) http://research.microsoft.com/~crusso/padl12 Philadelphia, Pennsylvania, USA, January 23-24, 2012 Co-located with ACM POPL'12 Abstract/Paper submission deadline: September 10th/17th, 2011 Conference Description == Declarative languages build on sound theoretical bases to provide attractive frameworks for application development. These languages have been successfully applied to many different real-world situations, ranging from data base management to active networks to software engineering to decision support systems. New developments in theory and implementation have opened up new application areas. At the same time, applications of declarative languages to novel problems raise numerous interesting research issues. Well-known questions include designing for scalability, language extensions for application deployment, and programming environments. Thus, applications drive the progress in the theory and implementation of declarative systems, and benefit from this progress as well. PADL is a forum for researchers and practitioners to present original work emphasizing novel applications and implementation techniques for all forms of declarative concepts, including, functional, logic, constraints, etc. Topics of interest include, but are not limited to: * Innovative applications of declarative languages * Declarative domain-specific languages and applications * Practical applications of theoretical results * New language developments and their impact on applications * Declarative languages and Software Engineering * Evaluation of implementation techniques on practical applications * Practical experiences and industrial applications * Novel uses of declarative languages in the classroom * Practical extensions such as constraint-based, probabilistic, and reactive languages. PADL'12 welcomes new ideas and approaches pertaining to applications and implementation of declarative languages. In this occasion PADL is co-located, as traditionally, with ACM POPL, which will be held immediately following PADL, January 25-27. The symposium will be held in Philadelphia, Pennsylvania, USA. Important Dates and Submission Guidelines = Abstract Submission:September 10, 2011 Paper Submission: September 17, 2011 Notification: October 22, 2011 Camera-ready: November 5, 2011 Symposium:January 23-24, 2012 Authors should submit an electronic copy of the full paper in PDF using the Springer LNCS format. The submission will be done through EasyChair conference system. If electronic submission is impossible, please contact the program chairs for information on how to submit hard copies. All submissions must be original work written in English. Submissions must be unpublished and not submitted for publication elsewhere. Work that already appeared in unpublished or informally published workshops proceedings may be submitted. PADL'12 will accept both technical and application papers: * Technical papers must describe original, previously unpublished research results. Technical papers must not exceed 15 pages in Springer LNCS format. * Application papers are a mechanism to present important practical applications of declarative languages that occur in industry or in areas of research other than Computer Science. Application papers will be published in the Springer-Verlag conference proceedings, and will be presented in a separate session. Application papers are expected to describe complex and/or real-world applications that rely on an innovative use of declarative languages. Application descriptions, engineering solutions and real-world experiences (both positive and negative) are solicited. The limit for application papers is 6 pages in Springer LNCS format. Program Committee = Marcello Balduccini, Intelligent Systems Department, Kodak Research Labs Edwin Brady, University of St Andrews, Scotland Henning Christiansen, Roskilde University, Denmark Agostino Dovier, University of Udine, Italy Matthew Flatt, University of Utah, USA Gopal Gupta, University of Texas at Dallas, USA John Hughes, Chalmers University of Technology, Sweden; Quviq AB Gabriele Keller, University of New South Wales, Australia Lunjin Lu,
Re: [Haskell-cafe] Web Framework to Show Experimental Data
Chris, thank you so much for pointing me into the right direction! From acid-state package description: Use regular Haskell data structures as your database... - exactly what I need! Snap looks very lively too, simple and you can code view in Haskell, which means concentrate on the problem, not on the boilerplate code! Capital advice, thanks! Chris Smith cdsmith at gmail.com wrote: Thu Jul 7 15:11:10 CEST 2011 Previous message: [Haskell-cafe] Web Framework to Show Experimental Data Next message: [Haskell-cafe] Installation failure crypto-api on MAC Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] On Thu, 2011-07-07 at 13:21 +0400, Dmitri O.Kondratiev wrote: 1) What to use for the Archive? Though input data is in JSON format, data generated from it is binary vectors. Not sure that CouchDB is a good choice in this case. What simple (Haskell lib + DB) combination one may advise that support concurrent read / write access with simple locking (don't need full transactional support)? I think this might be an excellent place to use Lemmih's acid-state package. If I read you correctly, you basically want to store a small enough amount of data that it's not a concern that it will need to reside in memory, and it's fairly regular so there won't be a lot of value in ad hoc queries? If this is the case, then acid-state will let you store it in Haskell data types, and with a bit of Template Haskell, you can access it in a persistent way. 2) Web framework? Don't need AJAX, just basic stuff but simple and easy to code forms? Well, I like Snap enough that I became a core developer for the project, but this seems like a place it's particularly well suited. If you just want something really simple and clean and easy to use, Snap is that thing. Snap itself is very lightweight, but if you want some kind of automated form support, then there is a snap backend for digestive-functors. That's a little complex for my taste, but it is one way to do composing of forms by sticking together form handlers, validators, and the like. Personally, I'm a fan of just using getParam to retrieve the data and writing Haskell code to do what you want. -- Chris ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Web Framework to Show Experimental Data
According to acid-state package description: Use regular Haskell data structures as your database... - exactly what I need! Snap looks very lively too, simple and you can code view in Haskell, which means concentrate on the problem, not on the boilerplate code! Capital advice, thanks Chris! Chris Smith cdsmith at gmail.com wrote: Thu Jul 7 15:11:10 CEST 2011 Previous message: [Haskell-cafe] Web Framework to Show Experimental Data Next message: [Haskell-cafe] Installation failure crypto-api on MAC Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] On Thu, 2011-07-07 at 13:21 +0400, Dmitri O.Kondratiev wrote: 1) What to use for the Archive? Though input data is in JSON format, data generated from it is binary vectors. Not sure that CouchDB is a good choice in this case. What simple (Haskell lib + DB) combination one may advise that support concurrent read / write access with simple locking (don't need full transactional support)? I think this might be an excellent place to use Lemmih's acid-state package. If I read you correctly, you basically want to store a small enough amount of data that it's not a concern that it will need to reside in memory, and it's fairly regular so there won't be a lot of value in ad hoc queries? If this is the case, then acid-state will let you store it in Haskell data types, and with a bit of Template Haskell, you can access it in a persistent way. 2) Web framework? Don't need AJAX, just basic stuff but simple and easy to code forms? Well, I like Snap enough that I became a core developer for the project, but this seems like a place it's particularly well suited. If you just want something really simple and clean and easy to use, Snap is that thing. Snap itself is very lightweight, but if you want some kind of automated form support, then there is a snap backend for digestive-functors. That's a little complex for my taste, but it is one way to do composing of forms by sticking together form handlers, validators, and the like. Personally, I'm a fan of just using getParam to retrieve the data and writing Haskell code to do what you want. -- Chris ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] how to change a process name
Quoth Kazu Yamamoto (=?iso-2022-jp?B?GyRCOzNLXE9CSScbKEI=?=) k...@iij.ad.jp, I would like to know how to change a process name in Haskell. When we are programming in C, we can change it by overriding argv on Unix. But I cannot find the same way to do in Haskell. Can anyone suggest how in Haskell? I'm not talking about the result of System.Environment.getProgName but talking about the process name which we can see by the ps command. If you mean, while the program is running - I don't agree that we can change it by overriding argv on UNIX. This might work on some specific operating systems, but not on all of them. I believe POSIX does not specify any way to do this, and in fact there is no reasonably portable way to do it. That's probably why Haskell doesn't support it. Now, if you mean argv[0] in execve(2), through which the caller determines the name for the new process ... I can't explain why Haskell's System.Posix.Process.executeFile doesn't support that, it looks like gratuitous breakage to me. Donn ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Jenkins/Hudson support for GHC warnings?
Hi, folks - I know there are quite a few Haskell projects using the Jenkins (formerly Hudson) continuous build system, and I wonder if anyone has figured out how to get it reliably collecting errors and warnings from GHC. The standard warnings pluginhttps://wiki.jenkins-ci.org/display/JENKINS/Warnings+Plugindoes a bad job - it tends to identify random (sometimes even empty) bits of build output as warnings. If you've configured it to behave better with GHC / hpc / QuickCheck / cabal-install, you'd be doing us a great service by sharing your tricks! Thanks, Bryan. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] How to ensure code executes in the context of a specific OS thread?
On Thu, Jul 7, 2011 at 12:41 AM, Simon Marlow marlo...@gmail.com wrote: On 06/07/2011 21:19, Jason Dagit wrote: On Wed, Jul 6, 2011 at 12:52 PM, Simon Marlowmarlo...@gmail.com wrote: On 06/07/11 17:14, David Barbour wrote: On Wed, Jul 6, 2011 at 8:09 AM, Simon Marlowmarlo...@gmail.com mailto:marlo...@gmail.com wrote: On 06/07/2011 15:42, Jason Dagit wrote: How can I make sure my library works from GHC (with arbitrary user threads) and from GHCI? Right, but usually the way this is implemented is with some cooperation from the main thread. [...] So you can't just do this from a library - the main thread has to be in on the game. I suppose you might wonder whether the GHC RTS could implement runInMainThread by preempting the main thread and running some different code on it. [...] I think the real issue is that GHC has a different behavior than GHCi, and I think this causes a lot of difficulties for people working on GUI and other FFI integration. Perhaps it would be possible to reverse the default roles of threads in GHCi: the main thread run user commands, and a second bound thread will process user interrupts and such. Well, GHCi has no main, so it doesn't seem surprising (to me) that it's different. However, if -fno-ghci-sandbox doesn't have any drawbacks we could just make it the default. I don't actually remember why we run each statement in a new thread, I think it just seemed like a prudent thing to do. +1 for this change. I'm not sure how we would know if there are drawbacks. Now that I think about it, the original reason may have been that if the computation grows a large stack, having it in a separate thread means GHCi can recover the memory. However we have been able to recover stack memory for some time now, so that is no longer an issue. Then by all means, please make -fno-ghci-sandbox the default! :) Thanks Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] NVIDIA's CUDA and Haskell
On 07/07/2011, at 1:36 AM, Johannes Waldmann wrote: actually libcuda is in /usr/lib/nvidia-current ... It still feels strange that I can build the examples from NVIDIA_GPU_Computing_SDK/C/src/ without modifying LDFLAGS. Okay. I've modified to configure script to fix the extra space issue, and to push LDFLAGS and CFLAGS onto the environment before cabal attempts the build. It should also correctly handle the --extra-[lib,include]-dirs flags now. Hopefully that goes smoother in future... I had a look though the makefiles used by the NVIDIA examples on my ubuntu test machine, but found no mention of searching /usr/lib/nvidia-current, so I'm not sure where that came from. Maybe that's part of the examples installer script, but I'll have to look into that later. Anyway, when running accelerate-examples --cuda I get mixed results, Is there a way to find out the expected results/failures for a recent accelerate package install? (So I can avoid reporting them.) That is a good point. Some of the tests are expected to fail but that's not written down anywhere yet; I'll add a README. The stack overflow errors come from the reference implementations, not the accelerate code; give the RTS more space to play in with +RTS -K32M or similar. Off the top of my head permute-hist, radixsort, one of the slice tests, and scanseg-sum fail. Thanks for the bug reports so far! -Trev ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] NLP libraries and tools?
On 7/7/11 3:38 AM, Aleksandar Dimitrov wrote: On Wed, Jul 06, 2011 at 07:27:10PM -0700, wren ng thornton wrote: I definitely agree with the iteratees comment, but I'm curious about the leaks you mention. I haven't run into leakiness issues (that I'm aware of) in my use of ByteStrings for NLP. The issue is this: strict ByteStrings retain pointers to the original chunk. The chunk is probably bigger than you'd want to keep in memory, if you, say, wanted to just keep one or two words. In my case, the chunk was some 65K (that was my Iteratee chunk size.) Oh, that issue. Yeah, I maintain an intern table and make sure that the copy in the table is a trimmed copy instead of keeping the whole string alive. I guess I should factor that part of my tagger out into a separate package :) I didn't know if you meant there was a technical issue, e.g. something about the fact that ByteStrings uses pinned memory (whereas Text doesn't IIRC). -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] NLP libraries and tools?
On 7/7/11 3:50 AM, Aleksandar Dimitrov wrote: It's actually a shame we're discussing this on -cafe and not on -nlp. Then again, maybe it's going to prompt somebody to join -nlp, and I'm gonna CC it there, because some folks over there might be interested, but not read -cafe. Quite :) When you mentioned Arabic for producing sentences that go on for ages you don't really need to go that far. I have had the doubtful pleasure of reading Kant and Hegel in their original versions. In German, it is sometimes still considered good style to write huge sentences. I once made it a point, just to stick it to a Kant-loving-person, to produce a sentence that spanned 2 whole pages (A4.) It wasn't even difficult. The Romans were big fans of that too (though there's only a small group of folks interested in doing NLP on Latin these days). I've only read Hegel et al. in translation, but the Latin I've read falls nicely into the notion of span. It doesn't, however, always fall nicely into a clause-based approach like Japanese does. Then again, that could be due to the poetic/rhetorical nature of the texts in question. I wonder if there's been any computational attempt to make the notion of span or discourse atoms rigorous enough for pragmatic use... I'm very much a works for me person in these matters. Mostly because I'm tired of linguists fighting each other over trivial matters. Give me something I can work with already! I can't help but be a (meta)theorist. But then, I'm of the firm opinion that theory must be grounded in actual practice, else it belongs more to the realm of theology than science. -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
