Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On Sun, Aug 1, 2010 at 11:44 AM, aditya siram aditya.si...@gmail.comwrote: Why are the Takusen module links on Hackage dead? I would also like to take this opportunity to request a Takusen tutorial and to thank you for this innovative library. http://blog.codersbase.com/2010/08/takusen-tutorial-part-1-hello-takusen.html There you go for a starter tutorial. For some reason the formatting on the published page is quite different compared with the interactive editor, and I got sick of fighting with it. I hope you can still read it well enough to get something out of it. Feed back welcome! I hope to write more in that series. Do you have any suggestions for a simple database application I could develop in the tutorial series? Thanks, Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Alistair Bayley wrote: We've put some effort into supporting older versions of ghc... Are there any distros still shipping with ghc-6.6? There are so many distros out there that it is hard to say no. But Debian, which tends to be very conservative, has not had a supported version with GHC 6.6 since February 2010. Jason Dagit wrote: ...darcs ...to drop support for a version of GHC ...If debian stable is still covered after the proposed changes then they are accepted automatically. If Debian stable would not be covered, then there is a discussion to reach consensus. There seems to be considerably more tension on the Darcs team between using new GHC features and supporting older GHC versions. Even hanging on to 6.8 support has been very painful for them. Like Darcs, Takusen is fundamental infrastructure. An effort should be made to support the oldest version of GHC still in common production use. Ideally that would mean supporting the version of GHC in Debian old-stable until at least a few months after Debian has stopped supporting it. According to that criterion, now is just about the right time to drop support for GHC 6.6. That said, people on platforms that old will probably not be needing the shiniest new features of Takusen, only the bug fixes. Thanks, Yitz ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Jason Dagit wrote: There you go for a starter tutorial. Thanks Jason, that's a great start. It already goes a long way towards making Takusen more accessible. I noticed that QuickCheck is still a dependency. That's not a good idea. It creates a lot of dependency problems, and most of the time the tests aren't needed anyway. It would also be nice if the various backends could be broken out into separate packages too, like for the other database packages. But I understand that might be a bit more work. Thanks, Yitz ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On Mon, Aug 2, 2010 at 5:48 AM, Yitzchak Gale g...@sefer.org wrote: Jason Dagit wrote: There you go for a starter tutorial. Thanks Jason, that's a great start. It already goes a long way towards making Takusen more accessible. I noticed that QuickCheck is still a dependency. That's not a good idea. It creates a lot of dependency problems, and most of the time the tests aren't needed anyway. You're right. I may have been able to avoid it by disabling the tests when I installed it. I'll have to look at it more. It would also be nice if the various backends could be broken out into separate packages too, like for the other database packages. But I understand that might be a bit more work. This is a definite goal! Thanks, Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Congrats on the release. Just one humble suggestion: your email assumes that the reader already knows what Takusen is. Reading the email, all I can infer is that it has something to do with databases, because of the ODBC reference. The only link in the email also does nothing to explain, since it just links to a ball of code. The README there also assumes that I already know that I want Takusen, and so doesn't bother to explain what it does, only how to use it. Ideally, release announcements should always include a 1-sentence executive summary of what the project is, before heading on to what is new. Say, The Takusen team would like to announce the latest release of Takusen, 0.8.6. Takusen is insert description here, 'cos I'm still not quite sure. This is primarily a bugfix release... - Dave On Sat, Jul 31, 2010 at 8:10 PM, Jason Dagit da...@codersbase.com wrote: Hello, The Takusen team would like to announce the latest release of Takusen, 0.8.6. This is primarily a bug fix and test suite enhancement release. The most notable new feature is limited support for string encodings with ODBC. The full list of changes is included at the at the end of this announcement. = Interested in Takusen development? = Takusen is looking for a new long term maintainer. I have agreed to fill the role of maintainer for now, but we are seeking an enthusiastic individual with spare time and a desire to lead Takusen development. = How to get it = This release is available on hackage: cabal update cabal install Takusen The source code is available on code.haskell.org: darcs get http://code.haskell.org/takusen = New features = - Alistair Bayley: * Database/PostgreSQL/PGFunctions.lhs: show instance for UUID prints Word64s in hex. * Database/PostgreSQL/Enumerator.lhs: add UUID and marshaling functions. * Database/PostgreSQL/PGFunctions.lhs: add UUID and marshalling functions. * Database/ODBC/OdbcFunctions.hsc: add support for different String encodings. New functions to marshal to/from various encodings (Latin1, UTF8, UTF16), and bind/get functions changed to use these. - Daniel Corson * binary data with postgres = Bug fixes = - Alistair Bayley: * Database/ODBC/OdbcFunctions.hsc: fix bug in mkBindBufferForStorable for Nothing (null) case: pass -1 (sqlNullData) as value size. * Database/ODBC/OdbcFunctions.hsc: use sqlNullData in bindParamString Nothing case, rather than -1. A bit more descriptive. * Database/ODBC/Enumerator.lhs: store bind buffers in stmt object, so we retain reference to them for lifetime of statement. Destroy with statement (well, lose the reference). Should fix bind errors found by Jason Dagit. * Database/ODBC/Enumerator.lhs: Oracle only supports two transaction isolation levels (like Postgres). String output bind parameters have max size 8000 (we use 7999 because module OdbcFunctions adds one to the size). * Database/ODBC/OdbcFunctions.hsc: string parameters have different SQL data types when binding columns (SQL_CHAR) and parameters (SQL_VARCHAR). Oracle only supports two transaction isolation levels. * Database/PostgreSQL/PGFunctions.lhs: fix byteaUnesc and add byteaEsc. = Refactoring = - Jason Dagit: * update urls in cabal file - Alistair Bayley: * Takusen.cabal: fixed QuickCheck version spec. * Takusen.cabal: bump version to 0.8.6. * Database/ODBC/OdbcFunctions.hsc: makeUtcTimeBuffer: pass struct size as both buffer size and data size in call to mkBindBuffer. * Database/ODBC/OdbcFunctions.hsc: mkBindBufferForStorable calls mkBindBuffer (reduces duplicated code). * Database/ODBC/Enumerator.lhs: add instance for EnvInquiry to change session char encoding. * Database/ODBC/Enumerator.lhs: add comments to beginTransaction. * Database/Util.lhs: print printArrayContents, to match function name. * Database/PostgreSQL/Enumerator.lhs: expose byteaEsc and byteaUnesc. = New tests and changes to tests = - Alistair Bayley: * Database/ODBC/Test/OdbcFunctions.lhs: added testBindDouble to test Nothing (null) case for Storable types. * Database/ODBC/Test/OdbcFunctions.lhs: split transaction isolation level tests so there is one test per level. String marshaling tests use 0x10FF40 as max unicode codepoint, because that keeps Oracle happy. Max size for String parameter buffer is 7999 (SQL Server restriction). Don't bury errors raised by tests; print, but continue. Fix fixture cleanup bug in testBindOutput (dropped wrong procedure). * Database/ODBC/Test/Enumerator.lhs: suffix xxx to bindOutput test expected value. * Database/PostgreSQL/Test/PGFunctions.lhs: tests for UUID. * Database/PostgreSQL/Test/Enumerator.lhs: round-trip test for UUID. * Database/PostgreSQL/Test/PGFunctions.lhs: test select of UUID value. *
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On Sun, Aug 1, 2010 at 9:10 AM, David Anderson d...@natulte.net wrote: Congrats on the release. Just one humble suggestion: your email assumes that the reader already knows what Takusen is. Reading the email, all I can infer is that it has something to do with databases, because of the ODBC reference. The only link in the email also does nothing to explain, since it just links to a ball of code. The README there also assumes that I already know that I want Takusen, and so doesn't bother to explain what it does, only how to use it. Sorry about that. The description from hackage: http://hackage.haskell.org/package/Takusen Takusen: Database library with left-fold interface, for PostgreSQL, Oracle, SQLite, ODBC. Takusen is a DBMS access library. Like HSQL and HDBC, we support arbitrary SQL statements (currently strings, extensible to anything that can be converted to a string). Takusen's unique selling point is safety and efficiency. We statically ensure all acquired database resources - such as cursors, connections, and statement handles - are released, exactly once, at predictable times. Takusen can avoid loading the whole result set in memory, and so can handle queries returning millions of rows in constant space. Takusen also supports automatic marshalling and unmarshalling of results and query parameters. These benefits come from the design of query result processing around a left-fold enumerator. Currently we fully support ODBC, Oracle, Sqlite, and PostgreSQL. Ideally, release announcements should always include a 1-sentence executive summary of what the project is, before heading on to what is new. Say, The Takusen team would like to announce the latest release of Takusen, 0.8.6. Takusen is insert description here, 'cos I'm still not quite sure. This is primarily a bugfix release... Thanks, I'll remember that. Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Why are the Takusen module links on Hackage dead? I would also like to take this opportunity to request a Takusen tutorial and to thank you for this innovative library. -deech On Sun, Aug 1, 2010 at 12:59 PM, Jason Dagit da...@codersbase.com wrote: On Sun, Aug 1, 2010 at 9:10 AM, David Anderson d...@natulte.net wrote: Congrats on the release. Just one humble suggestion: your email assumes that the reader already knows what Takusen is. Reading the email, all I can infer is that it has something to do with databases, because of the ODBC reference. The only link in the email also does nothing to explain, since it just links to a ball of code. The README there also assumes that I already know that I want Takusen, and so doesn't bother to explain what it does, only how to use it. Sorry about that. The description from hackage: http://hackage.haskell.org/package/Takusen Takusen: Database library with left-fold interface, for PostgreSQL, Oracle, SQLite, ODBC. Takusen is a DBMS access library. Like HSQL and HDBC, we support arbitrary SQL statements (currently strings, extensible to anything that can be converted to a string). Takusen's unique selling point is safety and efficiency. We statically ensure all acquired database resources - such as cursors, connections, and statement handles - are released, exactly once, at predictable times. Takusen can avoid loading the whole result set in memory, and so can handle queries returning millions of rows in constant space. Takusen also supports automatic marshalling and unmarshalling of results and query parameters. These benefits come from the design of query result processing around a left-fold enumerator. Currently we fully support ODBC, Oracle, Sqlite, and PostgreSQL. Ideally, release announcements should always include a 1-sentence executive summary of what the project is, before heading on to what is new. Say, The Takusen team would like to announce the latest release of Takusen, 0.8.6. Takusen is insert description here, 'cos I'm still not quite sure. This is primarily a bugfix release... Thanks, I'll remember that. Jason ___ 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] ANNOUNCE: Takusen 0.8.6
aditya.siram: Why are the Takusen module links on Hackage dead? Hmm. The links look fine: http://hackage.haskell.org/package/Takusen-0.8.6 this opportunity to request a Takusen tutorial and to thank you for this ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
I meant the links to the API docs. -deech [1] http://hackage.haskell.org/packages/archive/Takusen/0.8.6/doc/html/Database-ODBC-Enumerator.html On Sun, Aug 1, 2010 at 1:46 PM, Don Stewart d...@galois.com wrote: aditya.siram: Why are the Takusen module links on Hackage dead? Hmm. The links look fine: http://hackage.haskell.org/package/Takusen-0.8.6 this opportunity to request a Takusen tutorial and to thank you for this ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
A reasonable guess (I think, anyway): the reason is because support for ODBC, Oracle, Postgres etc isn't compiled in by default. You have to specify it with a flag with cabal install to get support for those things. But the reason they show up in API docs I would guess is because Haddock doesn't check constraints on what modules are 'exposed' given certain flags in the cabal file, it just looks over every 'exposed' module no matter what. In this case, it's not really a huge burden because I believe those modules each have almost identical interfaces, in particular they specify a 'connect' like function to get a database handle, and that's about all. The rest is common code under Database.Enumerator. On Sun, Aug 1, 2010 at 1:49 PM, aditya siram aditya.si...@gmail.com wrote: I meant the links to the API docs. -deech [1] http://hackage.haskell.org/packages/archive/Takusen/0.8.6/doc/html/Database-ODBC-Enumerator.html On Sun, Aug 1, 2010 at 1:46 PM, Don Stewart d...@galois.com wrote: aditya.siram: Why are the Takusen module links on Hackage dead? Hmm. The links look fine: http://hackage.haskell.org/package/Takusen-0.8.6 this opportunity to request a Takusen tutorial and to thank you for this ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- - Austin ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
I think it is just the ODBC backend that didn't generate http://hackage.haskell.org/packages/archive/Takusen/0.8.6/doc/html/Database-Enumerator.html Likely because the required C libs are not on Hackage, so that backend wasn't built. aditya.siram: I meant the links to the API docs. -deech [1] http://hackage.haskell.org/packages/archive/Takusen/0.8.6/doc/html/ Database-ODBC-Enumerator.html On Sun, Aug 1, 2010 at 1:46 PM, Don Stewart d...@galois.com wrote: aditya.siram: Why are the Takusen module links on Hackage dead? Hmm. The links look fine: http://hackage.haskell.org/package/Takusen-0.8.6 this opportunity to request a Takusen tutorial and to thank you for this ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Hi Jason, I've had my eye on the 'Takusen' approach for a while. In particular I think it's a wonderful idea to use the left-fold based interface. Takusen is also well supported and pretty stable, having been around for a while. Despite this, it seems to have a couple faults: * Few tutorials, aside from the Haddocks in Database.Enumerator * Very crufty old code in some sports (I see lots of references to GHC 6.6 and the 'extensible exceptions' changes in the cabal file among other places, which I believe we're all well beyond now. There also seems to be random tidbits that could be removed in favor of a library/removed because they're not necessary.) This should IMO all be removed under the argument Get a more recent GHC although people may disagree here. * It would be nice if we could make it depend on nicer libraries instead of rolling its own stuff - for example, we have Lato's excellent iteratee package, and Bas van Dijk has written a (IMO woefully underappreciated!) 'regions' package with encapsulate the lightweight monadic regions idea Oleg proposed. Of course, due to design, neither of these may work properly for Takusen's case, and if they did they would very likely facilitate API changes, but it's something I've been thinking about in the name of making the library smaller and more lightweight. These things were somewhat motivating me to perhaps write a small competitor library, but if Takusen is looking for a maintainer, it may certainly be more productive to remove some of the old cruft and modernize a bit of the existing code. Does anybody else have similar feelings? I am somewhat busy, but if someone else has some spare time to dedicate with me - either to coding or simply brainstorming right now - perhaps we could transform Takusen into a much more lightweight, better documented library. If it comes down to this I think I might be willing to maintain it, but I'd like feedback before just going out and wildly making changes to a venerable library like this. On Sat, Jul 31, 2010 at 1:10 PM, Jason Dagit da...@codersbase.com wrote: Hello, The Takusen team would like to announce the latest release of Takusen, 0.8.6. This is primarily a bug fix and test suite enhancement release. The most notable new feature is limited support for string encodings with ODBC. The full list of changes is included at the at the end of this announcement. = Interested in Takusen development? = Takusen is looking for a new long term maintainer. I have agreed to fill the role of maintainer for now, but we are seeking an enthusiastic individual with spare time and a desire to lead Takusen development. = How to get it = This release is available on hackage: cabal update cabal install Takusen The source code is available on code.haskell.org: darcs get http://code.haskell.org/takusen = New features = - Alistair Bayley: * Database/PostgreSQL/PGFunctions.lhs: show instance for UUID prints Word64s in hex. * Database/PostgreSQL/Enumerator.lhs: add UUID and marshaling functions. * Database/PostgreSQL/PGFunctions.lhs: add UUID and marshalling functions. * Database/ODBC/OdbcFunctions.hsc: add support for different String encodings. New functions to marshal to/from various encodings (Latin1, UTF8, UTF16), and bind/get functions changed to use these. - Daniel Corson * binary data with postgres = Bug fixes = - Alistair Bayley: * Database/ODBC/OdbcFunctions.hsc: fix bug in mkBindBufferForStorable for Nothing (null) case: pass -1 (sqlNullData) as value size. * Database/ODBC/OdbcFunctions.hsc: use sqlNullData in bindParamString Nothing case, rather than -1. A bit more descriptive. * Database/ODBC/Enumerator.lhs: store bind buffers in stmt object, so we retain reference to them for lifetime of statement. Destroy with statement (well, lose the reference). Should fix bind errors found by Jason Dagit. * Database/ODBC/Enumerator.lhs: Oracle only supports two transaction isolation levels (like Postgres). String output bind parameters have max size 8000 (we use 7999 because module OdbcFunctions adds one to the size). * Database/ODBC/OdbcFunctions.hsc: string parameters have different SQL data types when binding columns (SQL_CHAR) and parameters (SQL_VARCHAR). Oracle only supports two transaction isolation levels. * Database/PostgreSQL/PGFunctions.lhs: fix byteaUnesc and add byteaEsc. = Refactoring = - Jason Dagit: * update urls in cabal file - Alistair Bayley: * Takusen.cabal: fixed QuickCheck version spec. * Takusen.cabal: bump version to 0.8.6. * Database/ODBC/OdbcFunctions.hsc: makeUtcTimeBuffer: pass struct size as both buffer size and data size in call to mkBindBuffer. * Database/ODBC/OdbcFunctions.hsc: mkBindBufferForStorable calls mkBindBuffer (reduces duplicated code). * Database/ODBC/Enumerator.lhs: add instance for EnvInquiry to
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On 8/1/10 12:12 PM, austin seipp wrote: Hi Jason, I've had my eye on the 'Takusen' approach for a while. In particular I think it's a wonderful idea to use the left-fold based interface. Takusen is also well supported and pretty stable, having been around for a while. I agree; in fact, I use it for all of my database needs. * It would be nice if we could make it depend on nicer libraries instead of rolling its own stuff - for example, we have Lato's excellent iteratee package, and Bas van Dijk has written a (IMO woefully underappreciated!) 'regions' package with encapsulate the lightweight monadic regions idea Oleg proposed. Of course, due to design, neither of these may work properly for Takusen's case, and if they did they would very likely facilitate API changes, but it's something I've been thinking about in the name of making the library smaller and more lightweight. Making the library depend on more external libraries will actually make it more heavyweight since it will require the user to install more libraries just in order to use Takusen. I'm not saying that this is a bad thing, but I wouldn't automatically count it as a disadvantage that one can install Takusen without requiring lots of other libraries to be installed first. It looks to me like the iteratee package wouldn't be a good fit for Takusen because (as far I understand it) it is designed for the use case of reading raw data where in particular the chunks might not be aligned with the records being processed, whereas Takusen is designed for reading in very structured data. The regions package might work, although there are problems with the way that it handles exceptions that has been discussed previously on this list. Finally, a disadvantage of changing Takusen to use these kinds of external libraries is that it could actually make it *harder* to understand how to use it, since first the user would have to understand the concepts involved in the external libraries. Again, I'm not saying that any of these issues automatically make it a bad idea to modify Takusen to use external libraries, just that the current approach works well and is (in my opinion) already relatively simple and straightforward, and it would be unfortunate if this were lost without a clear benefit. Cheers, Greg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
At the risk of seeming a bit defensive, I'll respond to some of these points... Despite this, it seems to have a couple faults: * Few tutorials, aside from the Haddocks in Database.Enumerator True. I put a bit of effort in to writing the docs in Database.Enumerator as a sort of tutorial, but it doesn't work as well as a properly written tutorial. Perhaps this would be better placed on the wiki, but it's quite a bit of work, assuming you would prefer something more than a simple cut-n-paste from the generated docs. * Very crufty old code in some spots (I see lots of references to GHC 6.6 and the 'extensible exceptions' changes in the cabal file among other places, which I believe we're all well beyond now. There also seems to be random tidbits that could be removed in favor of a library/removed because they're not necessary.) This should IMO all be removed under the argument Get a more recent GHC although people may disagree here. Maybe... We've put some effort into supporting older versions of ghc, mainly because quite a few distributions have quite long update cycles. If you're stuck in an environment (some unis, some employers?) where you are only allowed tools from the last stable distribution, you may well be many releases behind current ghc. If everyone agrees that 6.8 should be the oldest ghc we should test and support, then that does make things a little simpler. Are there any distros still shipping with ghc-6.6? BTW, I thought extensible-exceptions first shipped with 6.10. I don't think everyone is off 6.8 yet, so we'd want to keep that cabal switch in for a little longer if we intend to support 6.8. * It would be nice if we could make it depend on nicer libraries instead of rolling its own stuff - for example, we have Lato's excellent iteratee package, and Bas van Dijk has written a (IMO woefully underappreciated!) 'regions' package with encapsulate the lightweight monadic regions idea Oleg proposed. Of course, due to design, neither of these may work properly for Takusen's case, and if they did they would very likely facilitate API changes, but it's something I've been thinking about in the name of making the library smaller and more lightweight. iteratee and regions were both released well after Takusen was written. I think iteratee is just the same idea generalised to other types (Binary, ByteStrings, IO, etc). Perhaps it would help to use it and standardise the interface, but I haven't looked into it at all. It looks like it might be a considerable amount of work. Using regions might be more feasible (i.e. easier), but again I haven't considered it. Takusen's implementation also pre-dates regions considerably, and it works well for us as is. The actual implementation is very little code. That is, in both cases I don't see a big benefit from switching over to these libraries, considering the amount of work I think it would take (esp for iteratee). There are plenty of other things on the to-do list which I think should take higher priority e.g. - splitting Takusen into multiple packages: a core interface, and then separate packages for each backend. - better docs, as you've requested. - support for blobs/clobs As Gregory just pointed out, using other libs adds further dependencies to Takusen. One of our earlier goals was to make it easy to install, which in the days before cabal meant fewer dependencies on external libs. cabal now mitigates that concern considerably, so perhaps we should relax more now when it comes to using external libs. Here is the list of things that I can think of right now which are currently internalised in Takusen, but which are also implementated in hackage libs: - extensible exceptions - EMonadIO - regions - iteratee I'm not saying the way it is now is right or best, but it got there through various historical decisions, which were made with the best information available at the time, and in environments that differ from the current. Alistair ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Using the generous resources of community.haskell.org I've created a mailing list for takusen discussions. I encourage interested parties to join that list and maybe move the takusen design discussion there: http://projects.haskell.org/cgi-bin/mailman/listinfo/takusen I've added the list in the CC. I've also created a trac instance for wiki/bug tracking: http://trac.haskell.org/takusen/report My comments are below. On Sun, Aug 1, 2010 at 12:55 PM, Alistair Bayley alist...@abayley.orgwrote: At the risk of seeming a bit defensive, I'll respond to some of these points... Despite this, it seems to have a couple faults: * Few tutorials, aside from the Haddocks in Database.Enumerator True. I put a bit of effort in to writing the docs in Database.Enumerator as a sort of tutorial, but it doesn't work as well as a properly written tutorial. Perhaps this would be better placed on the wiki, but it's quite a bit of work, assuming you would prefer something more than a simple cut-n-paste from the generated docs. More tutorials is a great idea. Perhaps I can write a few simple 'how to get started' examples and post them on my blog. Although, the wiki is a nice place too. Any preference? If I post it on my blog it might be easier to control the formatting and voice, but if it's on the wiki other can update it and it's in a central location. * Very crufty old code in some spots (I see lots of references to GHC 6.6 and the 'extensible exceptions' changes in the cabal file among other places, which I believe we're all well beyond now. There also seems to be random tidbits that could be removed in favor of a library/removed because they're not necessary.) This should IMO all be removed under the argument Get a more recent GHC although people may disagree here. Maybe... We've put some effort into supporting older versions of ghc, mainly because quite a few distributions have quite long update cycles. If you're stuck in an environment (some unis, some employers?) where you are only allowed tools from the last stable distribution, you may well be many releases behind current ghc. If everyone agrees that 6.8 should be the oldest ghc we should test and support, then that does make things a little simpler. Are there any distros still shipping with ghc-6.6? This same issues comes up fairly often on the darcs-users mailing list. My understanding of the way things are handled there, is that if there is ever a good reason to drop support for a version of GHC then the person who wants to drop support is supposed to look and see what is in Debian stable. If debian stable is still covered after the proposed changes then they are accepted automatically. If Debian stable would not be covered, then there is a discussion to reach consensus. The reasons it works are: a) support is dropped lazily when there is a real demand to do so, instead of artificially; b) letting people discuss it case-by-case allows the decision to be made with full context. BTW, I thought extensible-exceptions first shipped with 6.10. I don't think everyone is off 6.8 yet, so we'd want to keep that cabal switch in for a little longer if we intend to support 6.8. * It would be nice if we could make it depend on nicer libraries instead of rolling its own stuff - for example, we have Lato's excellent iteratee package, and Bas van Dijk has written a (IMO woefully underappreciated!) 'regions' package with encapsulate the lightweight monadic regions idea Oleg proposed. Of course, due to design, neither of these may work properly for Takusen's case, and if they did they would very likely facilitate API changes, but it's something I've been thinking about in the name of making the library smaller and more lightweight. iteratee and regions were both released well after Takusen was written. I think iteratee is just the same idea generalised to other types (Binary, ByteStrings, IO, etc). Perhaps it would help to use it and standardise the interface, but I haven't looked into it at all. It looks like it might be a considerable amount of work. I think that iteratees are a wonderful concept and I like them, but...I'm not terribly fond of the iteratee package. I find that with it's full generality that it is somewhat difficult to program with. I've actually found it easier to 'roll your own' when I need iteratees. My preference would be to switch to some later iteration of the iteratee design. I believe John Lato is currently working on a new API. Using regions might be more feasible (i.e. easier), but again I haven't considered it. Takusen's implementation also pre-dates regions considerably, and it works well for us as is. The actual implementation is very little code. I haven't looked at the regions package either, but it certainly sounds like a good idea to switch to it. That is, in both cases I don't see a big benefit from switching over to these libraries,
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On Sun, Aug 1, 2010 at 6:58 PM, Jason Dagit da...@codersbase.com wrote: This same issues comes up fairly often on the darcs-users mailing list. My understanding of the way things are handled there, is that if there is ever a good reason to drop support for a version of GHC then the person who wants to drop support is supposed to look and see what is in Debian stable. If debian stable is still covered after the proposed changes then they are accepted automatically. If Debian stable would not be covered, then there is a discussion to reach consensus. The reasons it works are: a) support is dropped lazily when there is a real demand to do so, instead of artificially; b) letting people discuss it case-by-case allows the decision to be made with full context. Do you know if they test on GHC 6.8? Or do they just avoid extensions and hope it works? =) Cheers, -- Felipe. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] ANNOUNCE: Takusen 0.8.6
On Sun, Aug 1, 2010 at 5:11 PM, Felipe Lessa felipe.le...@gmail.com wrote: On Sun, Aug 1, 2010 at 6:58 PM, Jason Dagit da...@codersbase.com wrote: This same issues comes up fairly often on the darcs-users mailing list. My understanding of the way things are handled there, is that if there is ever a good reason to drop support for a version of GHC then the person who wants to drop support is supposed to look and see what is in Debian stable. If debian stable is still covered after the proposed changes then they are accepted automatically. If Debian stable would not be covered, then there is a discussion to reach consensus. The reasons it works are: a) support is dropped lazily when there is a real demand to do so, instead of artificially; b) letting people discuss it case-by-case allows the decision to be made with full context. Do you know if they test on GHC 6.8? Or do they just avoid extensions and hope it works? =) They use a farm of buildbots to test: http://buildbot.darcs.net/ Jason ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] ANNOUNCE: Takusen 0.8.6
Hello, The Takusen team would like to announce the latest release of Takusen, 0.8.6. This is primarily a bug fix and test suite enhancement release. The most notable new feature is limited support for string encodings with ODBC. The full list of changes is included at the at the end of this announcement. = Interested in Takusen development? = Takusen is looking for a new long term maintainer. I have agreed to fill the role of maintainer for now, but we are seeking an enthusiastic individual with spare time and a desire to lead Takusen development. = How to get it = This release is available on hackage: cabal update cabal install Takusen The source code is available on code.haskell.org: darcs get http://code.haskell.org/takusen = New features = - Alistair Bayley: * Database/PostgreSQL/PGFunctions.lhs: show instance for UUID prints Word64s in hex. * Database/PostgreSQL/Enumerator.lhs: add UUID and marshaling functions. * Database/PostgreSQL/PGFunctions.lhs: add UUID and marshalling functions. * Database/ODBC/OdbcFunctions.hsc: add support for different String encodings. New functions to marshal to/from various encodings (Latin1, UTF8, UTF16), and bind/get functions changed to use these. - Daniel Corson * binary data with postgres = Bug fixes = - Alistair Bayley: * Database/ODBC/OdbcFunctions.hsc: fix bug in mkBindBufferForStorable for Nothing (null) case: pass -1 (sqlNullData) as value size. * Database/ODBC/OdbcFunctions.hsc: use sqlNullData in bindParamString Nothing case, rather than -1. A bit more descriptive. * Database/ODBC/Enumerator.lhs: store bind buffers in stmt object, so we retain reference to them for lifetime of statement. Destroy with statement (well, lose the reference). Should fix bind errors found by Jason Dagit. * Database/ODBC/Enumerator.lhs: Oracle only supports two transaction isolation levels (like Postgres). String output bind parameters have max size 8000 (we use 7999 because module OdbcFunctions adds one to the size). * Database/ODBC/OdbcFunctions.hsc: string parameters have different SQL data types when binding columns (SQL_CHAR) and parameters (SQL_VARCHAR). Oracle only supports two transaction isolation levels. * Database/PostgreSQL/PGFunctions.lhs: fix byteaUnesc and add byteaEsc. = Refactoring = - Jason Dagit: * update urls in cabal file - Alistair Bayley: * Takusen.cabal: fixed QuickCheck version spec. * Takusen.cabal: bump version to 0.8.6. * Database/ODBC/OdbcFunctions.hsc: makeUtcTimeBuffer: pass struct size as both buffer size and data size in call to mkBindBuffer. * Database/ODBC/OdbcFunctions.hsc: mkBindBufferForStorable calls mkBindBuffer (reduces duplicated code). * Database/ODBC/Enumerator.lhs: add instance for EnvInquiry to change session char encoding. * Database/ODBC/Enumerator.lhs: add comments to beginTransaction. * Database/Util.lhs: print printArrayContents, to match function name. * Database/PostgreSQL/Enumerator.lhs: expose byteaEsc and byteaUnesc. = New tests and changes to tests = - Alistair Bayley: * Database/ODBC/Test/OdbcFunctions.lhs: added testBindDouble to test Nothing (null) case for Storable types. * Database/ODBC/Test/OdbcFunctions.lhs: split transaction isolation level tests so there is one test per level. String marshaling tests use 0x10FF40 as max unicode codepoint, because that keeps Oracle happy. Max size for String parameter buffer is 7999 (SQL Server restriction). Don't bury errors raised by tests; print, but continue. Fix fixture cleanup bug in testBindOutput (dropped wrong procedure). * Database/ODBC/Test/Enumerator.lhs: suffix xxx to bindOutput test expected value. * Database/PostgreSQL/Test/PGFunctions.lhs: tests for UUID. * Database/PostgreSQL/Test/Enumerator.lhs: round-trip test for UUID. * Database/PostgreSQL/Test/PGFunctions.lhs: test select of UUID value. * Database/ODBC/Test/OdbcFunctions.lhs: set client charset to UTF8 when postgresql. * Database/Test/Enumerator.lhs: add order-bys to tests with unions. * Database/PostgreSQL/Test/PGFunctions.lhs: add order-by to union test. * Database/ODBC/Test/Enumerator.lhs: set char encoding to UTF8. inquire InfoDbmsName already returns lowercase. * Takusen.cabal: add random to build-depends for tests. * Database/Test/Enumerator.lhs: make test fixtures more friendly to MS Access. * Database/ODBC/Test/OdbcFunctions.lhs: tests modified for MS Access (date tests), plus use new char-encoding aware functions. * Database/ODBC/Test/Enumerator.lhs: change boundary dates test to not use union. Union seems to make MS Access choke. * Database/PostgreSQL/Test/PGFunctions.lhs: add tests for bytea, including QuickCheck roundtrip. * Database/PostgreSQL/Test/Enumerator.lhs: add bytea bind and select test.
