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• What are the most interesting equivalences arising from the Curry-Howard Isomorphism?

  - by Tom

  I came upon the Curry-Howard Isomorphism relatively late in my programming life, and perhaps this contributes to my being utterly fascinated by it. It implies that for every programming concept there exists a precise analogue in formal logic, and vice versa. Here's an "obvious" list of such analogies, off the top of my head: program/definition | proof type/declaration | proposition inhabited type | theorem function | implication function argument | hypothesis/antecedent function result | conclusion/consequent function application | modus ponens recursion | induction identity function | tautology non-terminating function | absurdity tuple | conjunction (and) disjoint union | exclusive disjunction (xor) parametric polymorphism | universal quantification So, to my question: what are some of the more interesting/obscure implications of this isomorphism? I'm no logician so I'm sure I've only scratched the surface with this list. For example, here are some programming notions for which I'm unaware of pithy names in logic: currying | "((a & b) => c) iff (a => (b => c))" scope | "known theory + hypotheses" And here are some logical concepts which I haven't quite pinned down in programming terms: primitive type? | axiom set of valid programs? | theory ? | disjunction (or)

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• Vim with Powershell

  - by Kevin Berridge

  I'm using gvim on Windows. In my _vimrc I've added: set shell=powershell.exe set shellcmdflag=-c set shellpipe=> set shellredir=> function! Test() echo system("dir -name") endfunction command! -nargs=0 Test :call Test() If I execute this function (:Test) I see nonsense characters (non number/letter ASCII characters). If I use cmd as the shell, it works (without the -name), so the problem seems to be with getting output from powershell into vim. Interestingly, this works great: :!dir -name As does this: :r !dir -name UPDATE: confirming behavior mentioned by David If you execute the set commands mentioned above in the _vimrc, :Test outputs nonsense. However, if you execute them directly in vim instead of in the _vimrc, :Test works as expected. Also, I've tried using iconv in case it was an encoding problem: :echo iconv( system("dir -name"), "unicode", &enc ) But this didn't make any difference. I could be using the wrong encoding types though. Anyone know how to make this work?

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• diffie-hellman ssh keyxchange

  - by Chuck

  Hi, I've set out to make a primitive SSH client in C#; you might remember me from posts such as http://stackoverflow.com/questions/2872279/c-primitive-ssh-connection-lowlevel hehe. Anyway, things are great up until the time when I initiate a DH key exchange. I've compared the traffic when I establish a ssh connection (from openssh client to openssh server), to the traffic when my client connects to the same openssh server. OpenSSH client - OpenSSH server (S for server, C for client): S: SSH-2.0-OpenSSH_5.1p1 Debian-6ubuntu2\r (saying hello) C: SSH-2.0-OpenSSH_5.2\r (introducing myself) C: Key Exchange Init (0x14 = 20) S: Key Exchange Init C: Diffie-Hellman GEX Request (0x22 = 34) (with DH GEX min, number of bits and max) S: Diffie-Hellman Key Exchange Reply (with P, G, etc.) C: Diffie-Hellman GEX Init S: Diffie-Hellman GEX Reply My client - OpenSSH server: S: SSH-2.0-OpenSSH_5.1p1 Debian-6ubuntu2\r (saying hello) C: SSH-2.0-Some_Name\r (introducing myself) C: Key Exchange Init (0x14 = 20) S: Key Exchange Init C: Diffie-Hellman GEX Request (0x22 = 34) (with DH GEX min, number of bits and max) and then a bogus TCP packet as reply (probably the server connection has been terminated after/upon GEX Request. I have yet to use AES128 (which I think is the encryption chosen, but I'm not sure how to verify this...), and I'm still sending in a non-compressed format, looking to get the P, G etc. values to make the DH calculations. So where I'm stranded is: RFC 4419 page 3 http://www.ietf.org/rfc/rfc4419.txt I've send SSH_MSG_KEY_DH_GEX_REQUEST, but the server does not respond SSH_MSG_KEX_DH_GEX_GROUP. Can anyone give me a little advice on what I'm not understanding here? Does the server not understand my GEX request (due to it expecting encryption, or?)? Any help is very much appreciated, thanks :)

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• Suggest joomla html editor extension/software

  - by DMin

  I've started using Joomla 1.5 recently and am using the TinyMCE online WYSIWYG editor that comes with the package to edit articles. I tend to write direct html and javascript rather than use the WYSIWYG functions, I find that after the first time the changes are applied(page updated) most of your html becomes 4-5 separate big paragraphs. Its very hard to find stuff in there cause the content has no formatting -- eg: <p><span id="psy_ass_span" class="pink_heading">Psychometric Assessment</span></p> <div id="psy_ass_div" class="pink_box"><img class="img_right" src="templates/teamwork.jpg" border="0" /> <p><strong>Emporkommen</strong> uses <strong>Psychometric assessment</strong> as a tool in order to gain insight into a person’s personality and psychological thinking. It can help develop team spirit in t <script src="plugins/editors/tinymce/jscripts/tiny_mce/themes/advanced/langs/en.js" type="text/javascript"></script> he workplace and assess an individual’s priorities.</p> Plus obviously there is no code highlighting in the editor so you can't figure out what is what. My question is, do you guys know of good(preferably non-commercial) extensions or other softwares or techniques that can make editing html code in Joomla 1.5 articles easier even after applying changes several times.

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• Academic question: typename

  - by Arman

  Hi, recently I accounted with a "simple problem" of porting code from VC++ to gcc/intel. The code is compiles w/o error on VC++: #include <vector> using std::vector; template <class T> void test_vec( std::vector<T> &vec) { typedef std::vector<T> M; /*==> add here typename*/ M::iterator ib=vec.begin(),ie=vec.end(); }; int main() { vector<double> x(100, 10); test_vec<double>(x); return 0; } then with g++ we have some unclear errors: g++ t.cpp t.cpp: In function 'void test_vec(std::vector<T, std::allocator<_CharT> >&)': t.cpp:13: error: expected `;' before 'ie' t.cpp: In function 'void test_vec(std::vector<T, std::allocator<_CharT> >&) [with T = double]': t.cpp:18: instantiated from here t.cpp:12: error: dependent-name 'std::M::iterator' is parsed as a non-type, but instantiation yields a type t.cpp:12: note: say 'typename std::M::iterator' if a type is meant If we add typename before iterator the code will compile w/o pb. If it is possible to make a compiler which can understand the code written in the more "natural way", then for me is unclear why we should add typename? Which rules of "C++ standards"(if there are some) will be broken if we allow all compilers to use without "typename"? kind regards Arman.

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• Problem with sfRemember cookie / sfGuard Remember me

  - by Tom

  I'm using Symfony 1.4 with Doctrine. Sorry if this is a silly question but what exactly does one need to build on top of the sfDoctrineGuardPlugin to get the "remember me" functionality working? When I login a user, the sfRemember cookie is created with the default 15-day lifetime, and the remember key is saved in the plugin's sf_guard_remember_key table. Without any tweaks to the plugin, the sfGuardSecurityUser SignIn() method creates the cookie, but the Signout() method erases it, leaving no cookie unless you're logged in! Signin(): sfContext::getInstance()->getResponse()->setCookie($remember_cookie, $key, time() + $expiration_age); Signout(): sfContext::getInstance()->getResponse()->setCookie($remember_cookie, '', time() - $expiration_age); I can see that the database table saves the cookie as a relation of sf_guard_user, but that's not much good if the cookie is gone.... I'd be grateful if someone could tell me what I'm missing here, and ideally, if I prevent the Signout() method from removing the cookie, do I need to write code to read the cookie myself or is this automated somewhere/somehow? I've got box-standard Symfony 1.4 and sfDoctrineGuardPlugin installations. It all just seems totally wrong and the documentation on this is non-existent. Any help would appreciated.

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• OpenGL - drawing 2D polygons shapes with texture

  - by plonkplonk

  I am trying to make a few effects in a C+GL game. So far I draw all my sprites as a quad, and it works. However, I am trying to make a large ring appear at times, with a texture following that ring, as it takes less memory than a quad with the ring texture inside. The type of ring I want to make is not a round-shaped GL mesh ring (the "tube" type) but a "paper" 2D ring. That way I can modify the "width" of the ring, getting more of the effect than a simple quad+ring texture. So far all my attempts have been...kind of ridiculous, as I don't understand GL's coordinates too well (and I can't really understand the available documentation...I am just a designer with no coder help or background. A n00b, basically). glBegin(GL_POLYGON); for(i = 0;i < 360; i += 10){ glTexCoord2f(0, 0); glVertex2f(Cos(i)*(H-10),Sin(i)H); glTexCoord2f(0, HP); glVertex2f(Sin(i)(H-10),Cos(i)*(H-10)); glTexCoord2f(WP, HP); glVertex2f(Cos(i)H,Sin(i)(H-10)); glTexCoord2f(WP, 0); glVertex2f(Sin(i)*H,Cos(i)*H); } glEnd(); This is my last attempt, and it seems to generate a "sunburst" from the right edge of the circle instead of a ring. It's an amusing effect but definitely not what I want. Other results included the circle looking exactly the same as the quad textured (aka drawing a sprite literally) or something that looked like a pop-art filter, by working on this train of thought. Seems like my logic here is entirely flawed, so, what would be the easiest way to obtain such a ring? No need to reply in code, just some guidance for a non-math-skilled user...

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• Set initial view with SkpWriter in Google Sketchup C++ SDK

  - by Peter Olsson

  How do you set the initial view for the model in an SKP file created with the SkpWriter in Google Sketchup C++ SDK? There has been an example in an older version of the SDK. Part of the source is posted here. I'm trying to use: m_pDoc->GetModel()->SetCamera(cameraDefn); The problem is that I'm not able to create a valid atlast::sketchup::CCameraDefinition. Non of the examples in the above post works: atlast::sketchup::CCameraDefinition cameraDefn; cameraDefn.Set(atlast::geometry::CPoint3d(793.838, -1262.6, 2603.16), atlast::geometry::CPoint3d(567.977, 338.199, 398.932), atlast::geometry::CUnitVector3d(-0.112657, 0.798459, 0.591415)); and: atlast::sketchup::CCameraDefinition cameraDefn; cameraDefn.Set(atlast::geometry::CPoint3d(793.838, -1262.6, 2603.16), atlast::geometry::CPoint3d(567.977, 338.199, 398.932), atlast::geometry::CUnitVector3d(-0.112657, 0.798459, 0.591415)); In the end I want the initial view to be the view you get from pressing the icon for Zoom extents followed by the Iso icon (the other way around is also ok). Right now I would settle for creating a valid atlast::sketchup::CCameraDefinition. Any better way to achieve this in the SKP-file?

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• [ASP.NET] Difficulties using custom control - RichTextEditor

  - by Chris

  I am working on a school project that uses ASP.NET. I found this TextEditor control ( http://blogs.msdn.com/kirti/archive/2007/11/10/rich-text-editor-is-here.aspx ) that I am trying to include but it isn't working. The error I am getting is: Error Rendering Control - TextEditor. An unhandled exception has occurred. Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index. I see this error when I go Design part of the editor. I just don't understand this error at all. Also I am a lil bit confused as there is no parameter called index. :( What I have done is reference the binary in my project and then on the page I am trying to use it have registered its namespace and assembly with this line: <%@ Register Assembly="RichTextEditor" Namespace="AjaxControls" TagPrefix="rtt" %> I then go ahead and try to add the control to the page with this line of code: <rtt:richtexteditor ID="TextEditor" Theme="Blue" runat="server" /> Any help would be much appreciated. I haven't done anything like add a custom control before.

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• Parallel scroll textarea and webpage with jquery

  - by Roger Rogers

  This is both a conceptual and how-to question: In wiki formatting, or non WYSIWYG editor scenarios, you typically have a textarea for content entry and then an ancillary preview pane to show results, just like StackOverflow. This works fairly well, except with larger amounts of text, such as full page wikis, etc. I have a concept that I'd like critical feedback/advice on: Envision a two pane layout, with the preview content on the left side, taking up ~ 2/3 of the page, and the textarea on the right side, taking up ~ 1/3 of the page. The textarea would float, to remain in view, even if the user scrolls the browser window. Furthermore, if the user scrolls the textarea content, supposing it has exceeded the textarea's frame size, the page would scroll so that the content presently showing in the textarea syncs/is parallel with the content showing in the browser window. I'm imagining a wiki scenario, where going back and forth between markup and preview is frustrating. I'm curious what others think; is there anything out there like this? Any suggestions on how to attack this functionality (ideally using jquery)? Thanks

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• Sqlite3 "chained" query

  - by Arrieta

  I need to create a configuration file from a data file that looks as follows: MAN1_TIME '01-JAN-2010 00:00:00.0000 UTC' MAN1_RX 123.45 MAN1_RY 123.45 MAN1_RZ 123.45 MAN1_NEXT 'MAN2' MAN2_TIME '01-MAR-2010 00:00:00.0000 UTC' MAN2_RX 123.45 [...] MAN2_NEXT 'MANX' [...] MANX_TIME [...] This file describes different "legs" of a trajectory. In this case, MAN1 is chained to MAN2, and MAN2 to MANX. In the original file, the chains are not as obvious (i.e., they are non-sequential). I've managed to read the file and store in an Sqlite3 database (I'm using the Python interface). The table is stored with three columns: Id, Par, and Val; for instance, Id='MAN1', Par='RX', and Val='123.45'. I'm interested in querying such database for obtaining the information related to 'n' legs. In English, that would be: "Select RX,RY,RZ for the next five legs starting on MAN1" So the query would go to MAN1, retrieve RX, RY, RZ, then read the parameter NEXT and go to that Id, retrieve RX, RY, RZ; read the parameter NEXT; go to that one ... like this five times. How can I pass such query with "dynamic parameters"? Thank you.

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• "Public" nested classes or not

  - by Frederick

  Suppose I have a class 'Application'. In order to be initialised it takes certain settings in the constructor. Let's also assume that the number of settings is so many that it's compelling to place them in a class of their own. Compare the following two implementations of this scenario. Implementation 1: class Application { Application(ApplicationSettings settings) { //Do initialisation here } } class ApplicationSettings { //Settings related methods and properties here } Implementation 2: class Application { Application(Application.Settings settings) { //Do initialisation here } class Settings { //Settings related methods and properties here } } To me, the second approach is very much preferable. It is more readable because it strongly emphasises the relation between the two classes. When I write code to instantiate Application class anywhere, the second approach is going to look prettier. Now just imagine the Settings class itself in turn had some similarly "related" class and that class in turn did so too. Go only three such levels and the class naming gets out out of hand in the 'non-nested' case. If you nest, however, things still stay elegant. Despite the above, I've read people saying on StackOverflow that nested classes are justified only if they're not visible to the outside world; that is if they are used only for the internal implementation of the containing class. The commonly cited objection is bloating the size of containing class's source file, but partial classes is the perfect solution for that problem. My question is, why are we wary of the "publicly exposed" use of nested classes? Are there any other arguments against such use?

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• WinForms - How do I access/call methods in UI thread from a separate thread without passing a delega

  - by Greg

  Hi, QUESTION: In .NET 3.5 WinForms apps, how do I access/call methods in UI thread from a separate thread, without passing a delegate? EXAMPLE: Say I have some code I want to run both (a) manually when the user clicks a button, and (b) periodically called by a process which is running in a separate non-mainUI thread but without passing a delegate. [Simplistically I'm thinking that the class that has this method is already been constructed, and the main UI thread has a handle to it, therefore if the process running in the separate thread could just get a handle to it from the main-UI thread it could call it. Hopefully this is not a flawed concept] BACKGROUND: I'm actually after a way to do the above for the case where my separate process thread is actually a job I schedule using quartz.net. The way the scheduler works I can't seem to actually pass in a delegate. There is a way to pass JobDetails, however it only seems to caters for things like string, int, etc. Hence what I'm after is a way to access the MainForm class for example, to call a method on it, from within the quartz.net job which runs in a separate thread. Thanks

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• .NET regex's not working - 1# check beginning of text entered #2 check structure

  - by Olly

  OK it has unfortunately been a while since I've used REGEX and I am struggling to wonder why its not working with my project. I have used Regex Tester which says my two tests are valid but when it comes to testing in my project they get rejected. 1) Check the text starts with certain characters [RegularExpression("(spAPP)",ErrorMessage = "Stored procedures must begin with spAPP")] This seems to accept spAPP on it's own, but not something like spAPPabcdef which I want it to. I am struggling to find the "Ignore rest of the text" attribute with REGEX. 2) A bit more complicated. I have certain naming conventions for AD groups, so an example would be "UK ROLE IT APPLICATION DEV ADMIN", up to the role name there are standards (so I need the "UK ROLE IT APPLICATION DEV" checked. [RegularExpression(@"((UK|FRANCE|GERMANY|USA)\s(ROLE)\s(IT|NON-IT)\s(APPLICATION)\s(DEV|TEST|LIVE))", ErrorMessage = "Please use AD naming standards.")] I think it might be the fact I am using () around all the words, but its easier to read in my code. The RegexTester I found seems to indicate that it's right, but again, in my .NET project, it rejects it. Thanks,

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• FlashBuilder 4 and Zend Framework error

  - by sig

  I am trying to use adobe flash builder 4 with a php service. I had it set up an older macbook running leopard, but just tried to set it up on my new laptop running snow leopard. I did all the same steps.. set the Flex Server to be PHP, set the web root and url. Then I go to Data-Connect To PHP and point it to a php file I have in my web root. It says it needs to install Zend, and claims it does so successfully, but then when I try to continue, I get an error. I don't understand.. this same setup works on my older laptop. (Yes, I checked the amf.production was false) Unable to retrieve operations and entities from the file Make sure that Zend Framework is installed correctly and the parameter "amf.production" is not set to true in the amf_config.ini file located in the project output folder. false), true);$default_config-merge(new Zend_Config_Ini($configfile, 'zendamf'));$default_config-setReadOnly();$amf = $default_config-amf;// Store configuration in the registryZend_Registry::set("amf-config", $amf);// Initialize AMF Server$server = new Zend_Amf_Server();$server-setProduction($amf-production);if(isset($amf-directories)) { $dirs = $amf-directories-toArray(); foreach($dirs as $dir) { // get the first character of the path. // If it does not start with slash then it implies that the path is relative to webroot. Else it will be treated as absolute path $length = strlen($dir); $firstChar = $dir; if($length = 1) $firstChar = $dir[0]; if($firstChar != "/"){ // if the directory is ./ path then we add the webroot only. if($dir == "./"){ $server-addDirectory($webroot); }else{ $tempPath = $webroot . "/" . $dir; $server-addDirectory($tempPath); } }else{ $server-addDirectory($dir); } }}// Initialize introspector for non-productionif(!$amf-production) { $server-setClass('Zend_Amf_Adobe_Introspector', '', array("config" = $default_config, "server" = $server)); $server-setClass('Zend_Amf_Adobe_DbInspector', '', array("config" = $default_config, "server" = $server));}// Handle requestecho $server-handle();

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• Getting svn: E170000: Unrecognized URL scheme for my custom Svn Gradle plugin

  - by Ip Doh

  I wrote a custom gradle plugin using groovy to do basic svn tasks like, Checkout, Clean, Tag etc. The groovy class calls the svn command line client to do these operations, It works fine when i run it on my windows system but the same plugin gives the following error when i run it on a linux system (Centos). svn: E170000: Unrecognized URL scheme for '%22https://source.mycompany.net/svn/MyProject/trunk%22' Am able to make the same calls to the command line client through the command prompt or shell script without any issues. So what is the difference with Here is my code sample String command =String.format("svn co -r %d --non-interactive --trust-server-cert -- username %s --password %s --depth infinity \"%s\" \"%s\"", getRevision(), getUserName(), getUserPassword(), getSrcUrl(), getDir()); Process svnProcess = Runtime.getRuntime().exec(command); BufferedReader stdInput = new BufferedReader(new InputStreamReader(svnProcess.getInputStream())); BufferedReader stdError = new BufferedReader(new InputStreamReader(svnProcess.getErrorStream())); String statusOutputLine ="" while ((statusOutputLine = stdInput.readLine()) != null) { logger.quiet(" " + statusOutputLine); } while (( statusOutputLine = stdError.readLine()) != null) { logger.error(statusOutputLine) throw new Exception(statusOutputLine) } logger.quiet("Successfully Checked out the work space") i do have neon installed on the system -bash-4.1$ svn --version svn, version 1.6.11 (r934486) compiled Jun 25 2011, 11:30:15 Copyright (C) 2000-2009 CollabNet. Subversion is open source software, see http://subversion.tigris.org/ This product includes software developed by CollabNet (http://www.Collab.Net/). The following repository access (RA) modules are available: ra_neon : Module for accessing a repository via WebDAV protocol using Neon. handles 'http' scheme handles 'https' scheme ra_svn : Module for accessing a repository using the svn network protocol. with Cyrus SASL authentication handles 'svn' scheme ra_local : Module for accessing a repository on local disk. handles 'file' scheme

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• Extending ASP.NET role providers

  - by Quick Joe Smith

  Because the RoleProvider interface seems to treat roles as nothing more than simple strings, I'm wondering if there is any non-hacky way to apply an optional value for a role on a per-user basis. Our current login management system implements roles as key-value pairs, where the value part is optional and usually used to clarify or limit the permissions granted by a role. For example, a role 'editor' might contain a user 'barry', but for 'barry' it will have an optional value 'raptors', which the system would interpret to mean that Barry can only edit articles filed under the 'raptors' category. I have seen elsewhere a suggestion to simply create additional delimited roles, such as 'editor.raptors' or somesuch. That's not really going to be ideal because it would bloat the number of roles greatly, and I can tell it's going to be a very hard sell to replace our current implementation (which is also very less than ideal, but has the advantage of being custom made to work with our user database). I can tell already that the concatenation method mentioned above is going to involve a lot of tedious string-splitting and partial matching. Is there a better way?

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• How to use SQLAlchemy to dump an SQL file from query expressions to bulk-insert into a DBMS?

  - by Mahmoud Abdelkader

  Please bear with me as I explain the problem, how I tried to solve it, and my question on how to improve it is at the end. I have a 100,000 line csv file from an offline batch job and I needed to insert it into the database as its proper models. Ordinarily, if this is a fairly straight-forward load, this can be trivially loaded by just munging the CSV file to fit a schema, but I had to do some external processing that requires querying and it's just much more convenient to use SQLAlchemy to generate the data I want. The data I want here is 3 models that represent 3 pre-exiting tables in the database and each subsequent model depends on the previous model. For example: Model C --> Foreign Key --> Model B --> Foreign Key --> Model A So, the models must be inserted in the order A, B, and C. I came up with a producer/consumer approach: - instantiate a multiprocessing.Process which contains a threadpool of 50 persister threads that have a threadlocal connection to a database - read a line from the file using the csv DictReader - enqueue the dictionary to the process, where each thread creates the appropriate models by querying the right values and each thread persists the models in the appropriate order This was faster than a non-threaded read/persist but it is way slower than bulk-loading a file into the database. The job finished persisting after about 45 minutes. For fun, I decided to write it in SQL statements, it took 5 minutes. Writing the SQL statements took me a couple of hours, though. So my question is, could I have used a faster method to insert rows using SQLAlchemy? As I understand it, SQLAlchemy is not designed for bulk insert operations, so this is less than ideal. This follows to my question, is there a way to generate the SQL statements using SQLAlchemy, throw them in a file, and then just use a bulk-load into the database? I know about str(model_object) but it does not show the interpolated values. I would appreciate any guidance for how to do this faster. Thanks!

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• Instantiate type variable in Haskell

  - by danportin

  EDIT: Solved. I was unware that enabling a language extension in the source file did not enable the language extension in GHCi. The solution was to :set FlexibleContexts in GHCi. I recently discovered that type declarations in classes and instances in Haskell are Horn clauses. So I encoded the arithmetic operations from The Art of Prolog, Chapter 3, into Haskell. For instance: fac(0,s(0)). fac(s(N),F) :- fac(N,X), mult(s(N),X,F). class Fac x y | x -> y instance Fac Z (S Z) instance (Fac n x, Mult (S n) x f) => Fac (S n) f pow(s(X),0,0) :- nat(X). pow(0,s(X),s(0)) :- nat(X). pow(s(N),X,Y) :- pow(N,X,Z), mult(Z,X,Y). class Pow x y z | x y -> z instance (N n) => Pow (S n) Z Z instance (N n) => Pow Z (S n) (S Z) instance (Pow n x z, Mult z x y) => Pow (S n) x y In Prolog, values are insantiated for (logic) variable in a proof. However, I don't understand how to instantiate type variables in Haskell. That is, I don't understand what the Haskell equivalent of a Prolog query ?-f(X1,X2,...,Xn) is. I assume that :t undefined :: (f x1 x2 ... xn) => xi would cause Haskell to instantiate xi, but this gives a Non type-variable argument in the constraint error, even with FlexibleContexts enabled.

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• "User Friendly" .net compatible Regex/Text matching tools?

  - by Binary Worrier

  Currently in our software we provide a hook where we call a DLL built by our clients to parse information out of documents we are processing (the DLL takes in some text (or a file) and returns a list of name/value pairs). e.g. We're given a Word doc or Text file to Archive. We do various things to the file, and call a DLL that will return "pertinent" information about the file. Among other things we store that "pertinent" data for posterity. What is considered "pertinent" depends on the client and the type of the document, we don't care, we get it and store it. I've been asked to develop a user friendly "something" that will allow a non-programmer user to "configure" how to get this data from a plain text document (<humor>The user story ends with the helpful suggestion/query "We could use regex for this?"</humor>) It's safe to assume that a list of regex's isn't going to cut this, I've written some of these parsers for customers, the regex's to do these would be hedious and some of them can't be done by regex's. Also one of the requirements above is "user friendly" which negates anything that has users seeing or editing regex expressions. As you can guess, I don't have a fortune of time to do this, and am wondering is there anything out there that I can plug in to our app that has a nice front end and does exactly what I need? :) No? Whadda mean no! . . . sigh Ok then failing that, anything out there that "visually" builds regex's and/or other pattern matching expressions, and then allows one to run those expressions against some text? The MS BRE will do what I want, but I need something prettier that looks less like code. Thanks guys,

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• OpenGL/Carbon/Cocoa Memory Management Autorelease issue

  - by Stephen Furlani

  Hoooboy, I've got another doozy of a memory problem. I'm creating a Carbon (AGL) Window, in C++ and it's telling me that I'm autorelease-ing it without a pool in place. uh... what? I thought Carbon existed outside of the NSAutoreleasePool... When I call glEnable(GL_TEXTURE_2D) to do some stuff, it gives me a EXC_BAD_ACCESS warning - but if the AGL Window is never getting release'd, then shouldn't it exist? Setting set objc-non-blocking-mode at (gdb) doesn't make the problem go away. So I guess my question is WHAT IS UP WITH CARBON/COCOA/NSAutoreleasePool? And... are there any resources for Objective-C++? Because crap like this keeps happening to me. Thanks, -Stephen --- CODE --- Test Draw Function void Channel::frameDraw( const uint32_t frameID) { eq::Channel::frameDraw( frameID ); getWindow()->makeCurrent(false); glEnable(GL_TEXTURE_2D); // Throws Error Here } Make Current (Equalizer API from Eyescale) void Window::makeCurrent( const bool useCache ) const { if( useCache && getPipe()->isCurrent( this )) return; _osWindow->makeCurrent(); } void AGLWindow::makeCurrent() const { aglSetCurrentContext( _aglContext ); AGLWindowIF::makeCurrent(); if( _aglContext ) { EQ_GL_ERROR( "After aglSetCurrentContext" ); } } _aglContext is a valid memory location (i.e. not NULL) when I step through. -S!

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• Lua Operator Overloading

  - by Pessimist

  I've found some places on the web saying that operators in Lua are overloadable but I can't seem to find any example. Can someone provide an example of, say, overloading the + operator to work like the .. operator works for string concatenation? EDIT 1: to Alexander Gladysh and RBerteig: If operator overloading only works when both operands are the same type and changing this behavior wouldn't be easy, then how come the following code works? (I don't mean any offense, I just started learning this language): printf = function(fmt, ...) io.write(string.format(fmt, ...)) end Set = {} Set.mt = {} -- metatable for sets function Set.new (t) local set = {} setmetatable(set, Set.mt) for _, l in ipairs(t) do set[l] = true end return set end function Set.union (a,b) -- THIS IS THE PART THAT MANAGES OPERATOR OVERLOADING WITH OPERANDS OF DIFFERENT TYPES -- if user built new set using: new_set = some_set + some_number if type(a) == "table" and type(b) == "number" then print("building set...") local mixedset = Set.new{} for k in pairs(a) do mixedset[k] = true end mixedset[b] = true return mixedset -- elseif user built new set using: new_set = some_number + some_set elseif type(b) == "table" and type(a) == "number" then print("building set...") local mixedset = Set.new{} for k in pairs(b) do mixedset[k] = true end mixedset[a] = true return mixedset end if getmetatable(a) ~= Set.mt or getmetatable(b) ~= Set.mt then error("attempt to 'add' a set with a non-set value that is also not a number", 2) end local res = Set.new{} for k in pairs(a) do res[k] = true end for k in pairs(b) do res[k] = true end return res end function Set.tostring (set) local s = "{" local sep = "" for e in pairs(set) do s = s .. sep .. e sep = ", " end return s .. "}" end function Set.print (s) print(Set.tostring(s)) end s1 = Set.new{10, 20, 30, 50} s2 = Set.new{30, 1} Set.mt.__add = Set.union -- now try to make a new set by unioning a set plus a number: s3 = s1 + 8 Set.print(s3) --> {1, 10, 20, 30, 50}

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• IE: Undocumented "cache" attribute defined for input elements?

  - by aefxx

  Hi everybody. I've stumpled upon a strange behavior in IE(6/7/8) that drives me nuts. Given the following markup: <input type="text" value="foo" class="bar" cache="yes" send="no" /> Please note that the cache attribute is set to yes. However IE somehow manages to change the attributes value to cache="cache" when rendering the DOM. So, I wonder, is there an undocumented feature that I'm not aware of? I've googled about an hour now but couldn't find any info on this (not even on MSDN). NOTE I'm aware that adding custom attributes is non-standard compliant and that boolean attributes should be noted as attribute="attribute. Nevertheless I have to cope with these as they were introduced long before I joined the team. These custom attributes are used in conjunction with javascript to provide a more user friendly approach to form handling (and it works out quite well with Firefox/Safari/Opera/Chrome). I know that I could simply convert these custom attributes to x-data attributes that will be introduced with HTML5 but that would take me several hours of extra work - sigh. Hope, I made myself clear. Thanks in advance.

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• How to get interpolated message in NHibernate.Validator

  - by SztupY

  Hi! I'm trying to integrate NHibernate.Validator with ASP.NET MVC client side validations, and the only problem I found is that I simply can't convert the non-interpolated message to a human-readable one. I thought this would be an easy task, but turned out to be the hardest part of the client-side validation. The main problem is that because it's not server-side, I actually only need the validation attributes that are being used, and I don't actually have an instance or anything else at hand. Here are some excerpts from what I've been already trying: // Get the the default Message Interpolator from the Engine IMessageInterpolator interp = _engine.Interpolator; if (interp == null) { // It is null?? Oh, try to create a new one interp = new NHibernate.Validator.Interpolator.DefaultMessageInterpolator(); } // We need an instance of the object that needs to be validated, se we have to create one object instance = Activator.CreateInstance(Metadata.ContainerType); // we enumerate all attributes of the property. For example we have found a PatternAttribute var a = attr as PatternAttribute; // it seems that the default message interpolator doesn't work, unless initialized if (interp is NHibernate.Validator.Interpolator.DefaultMessageInterpolator) { (interp as NHibernate.Validator.Interpolator.DefaultMessageInterpolator).Initialize(a); } // but even after it is initialized the following will throw a NullReferenceException, although all of the parameters are specified, and they are not null (except for the properties of the instance, which are all null, but this can't be changed) var message = interp.Interpolate(new InterpolationInfo(Metadata.ContainerType, instance, PropertyName, a, interp, a.Message)); I know that the above is a fairly complex code for a seemingly simple question, but I'm still stuck without solution. Is there any way to get the interpolated string out of NHValidator?

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• Can I copy/clone a function in JavaScript?

  - by Craig Stuntz

  I'm using jQuery with the validators plugin. I would like to replace the "required" validator with one of my own. This is easy: jQuery.validator.addMethod("required", function(value, element, param) { return myRequired(value, element, param); }, jQuery.validator.messages.required); So far, so good. This works just fine. But what I really want to do is call my function in some cases, and the default validator for the rest. Unfortunately, this turns out to be recursive: jQuery.validator.addMethod("required", function(value, element, param) { // handle comboboxes with empty guids if (someTest(element)) { return myRequired(value, element, param); } return jQuery.validator.methods.required(value, element, param); }, jQuery.validator.messages.required); I looked at the source code for the validators, and the default implementation of "required" is defined as an anonymous method at jQuery.validator.messages.required. So there is no other (non-anonymous) reference to the function that I can use. Storing a reference to the function externally before calling addMethod and calling the default validator via that reference makes no difference. What I really need to do is to be able to copy the default required validator function by value instead of by reference. But after quite a bit of searching, I can't figure out how to do that. Is it possible? If it's impossible, then I can copy the source for the original function. But that creates a maintenance problem, and I would rather not do that unless there is no "better way."

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