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  • Automatically support new changes with Python.

    - by Zachary Brown
    I was working on a program,that I need to support new additions. Hmmm. Let me give you some background on the program. It is an educational software program that has quizzes for the user to take, just to gain odd knowledge. Now, It currently supports 6 subjects, all organized with directores on the HDD ( i.e. the Science directory is called science. ) and the way you launch the subject to see what quizzes you have to take is by pushing a button on the home screen. This sort of thing prevents easy subject additions. I want to be able to add a subject later on without having to recode the home screen and re organize all the buttons. I would use a Listbox and os.listdir(...), but I was kind of wanting something prettier than a Listbox. I am using Tkinter on Windows. The Python version I am using is 2.6 Is there a "fancy" listbox sort of thing that can be styled to work with the background?

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  • Wait for function to finish before starting again.

    - by Matthew Brown
    Good Morning, I am trying to call the same function everytime the user presses a button. Here is what happens at the moment.. User clicks button - Calls function - function takes 1000ms+ to finish (due to animation with jQuery and AJAX calls) What I want to happen is every time the user presses the button it adds the function to the queue, waits for the previous call to finish, and then starts.. Is this possible? Sorry if my explanation is a bit confusing.. Thanks Matthew

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  • Object as an array

    - by owca
    I need to create class Dog and PurebredDog extending Dog. Problem is that Dog can be at once single object and array of objects (Dogs and PurebreedDogs : Dog pack[]={new Dog(76589,"As","black",18, "Ann","Kowalsky"), new PurebreedDog(45321,"Labrador","Elf","black",25, "Angus","Mati","Barbara","Smith"), new Dog(102467,"Gamma","brown",89, "Josh","Coke"), new PurebreedDog(9678,"York","Theta","brown",8, "Emka","Figaro","Alice","Cat")}; for(int i=0; i < pack.length; i++) System.out.println(pack[i]+"\n\n"); How to write proper constructor for Dog ?

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  • Porting a piece of Lisp code to Clojure (PAIP)

    - by Robert Brown
    I'm reading Paradigms of Artificial Intelligence Programming (PAIP) by Peter Norvig and I'm trying to write all the code in Clojure rather than common Lisp. However I'm stuck on this piece of code on page 39: (defparameter *simple-grammar* '((sentence -> (noun-phrase verb-phrase)) (noun-phrase -> (Article Noun)) (verb-phrase -> (Verb noun-phrase)) (Article -> the a) (Noun -> man ball woman table) (Verb -> hit took saw liked)) "A grammar for a trivial subset of English.") (defvar *grammar* *simple-grammar*) How can I translate this into Clojure? Thanks.

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  • Codeigniter: Select from multiple tables

    - by Kevin Brown
    How can I select rows from two or more tables? I'm setting default fields for a form, and I need values from two tables... My current code reads: $this->CI->db->select('*'); $this->CI->db->from('user_profiles'); $this->CI->db->where('user_id' , $id); $user = $this->CI->db->get(); $user = $user->row_array(); $this->CI->validation->set_default_value($user);

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  • Fuzzy string matching algorithm in Python

    - by Mridang Agarwalla
    Hi guys, I'm trying to find some sort of a good, fuzzy string matching algorithm. Direct matching doesn't work for me — this isn't too good because unless my strings are a 100% similar, the match fails. The Levenshtein method doesn't work too well for strings as it works on a character level. I was looking for something along the lines of word level matching e.g. String A: The quick brown fox. String B: The quick brown fox jumped over the lazy dog. These should match as all words in string A are in string B. Now, this is an oversimplified example but would anyone know a good, fuzzy string matching algorithm that works on a word level. Thanks in advance.

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  • What's wrong with my regex

    - by Tom Brown
    Yes I know its usually a bad idea to parse HTML using RegEx, but that aside can someone explain the fault here: string outputString = Regex.Replace(inputString, @"<?(?i:script|embed|object|frameset|frame|iframe|metalink|style|html|img|layer|ilayer|meta|applet)(.|\n)*?>", ""); if (outputString != inputString) { Console.WriteLine("unwanted tags detected"); } It certainly detects the intended tags like: <script> and <html>, but it also rejects strings I want to allow such as <B>Description</B> and <A href="http://www.mylink.com/index.html">A Link containing 'HTML'</A>

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  • How to transform phrases and words into MD5 hash?

    - by brilliant
    Can anyone, please, explain to me how to transform a phrase like "I want to buy some milk" into MD5? I read Wikipedia article on MD5, but the explanation given there is beyond my comprehension: "MD5 processes a variable-length message into a fixed-length output of 128 bits. The input message is broken up into chunks of 512-bit blocks (sixteen 32-bit little endian integers)" "sixteen 32-bit little endian integers" is already hard for me. I checked the article on little endians and didn't understand a bit. However, the examples of some phrases and their MD5 hashes are very nice: MD5("The quick brown fox jumps over the lazy dog") = 9e107d9d372bb6826bd81d3542a419d6 MD5("The quick brown fox jumps over the lazy dog.") = e4d909c290d0fb1ca068ffaddf22cbd0 Can anyone, please, explain to me how this MD5 algorithm works on some very simple example? And also, perhaps you know some software or a code that would transform phrases into their MD5. If yes, please, let me know.

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  • WinForms: finding the size of a minimized form without going to FormWindowState.Normal

    - by Doc Brown
    Is there an easy way to determine the size of a Form it does have in WindowState=Normal, without actually changing the Form state? Here is what I do now (C# code): public class MyForm: Form { public void MyMethod() { // ... FormWindowState oldState = this.WindowState; this.WindowState = FormWindowState.Normal; Point windowLocation = this.Location; Size windowSize = this.Size; this.WindowState = oldState; // ... } } This is what I would like the code to look like: public class MyForm: Form { public void MyMethod() { // no state change here Point windowLocation = this.NormalStateLocation; Size windowSize = this.NormalStateSize; } } In fact there are no NormalStateLocation or NormalStateSize properties in Windows Forms.

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  • What are the primitive Forth operators?

    - by Barry Brown
    I'm interested in implementing a Forth system, just so I can get some experience building a simple VM and runtime. When starting in Forth, one typically learns about the stack and its operators (DROP, DUP, SWAP, etc.) first, so it's natural to think of these as being among the primitive operators. But they're not. Each of them can be broken down into operators that directly manipulate memory and the stack pointers. Later one learns about store (!) and fetch (@) which can be used to implement DUP, SWAP, and so forth (ha!). So what are the primitive operators? Which ones must be implemented directly in the runtime environment from which all others can be built? I'm not interested in high-performance; I want something that I (and others) can learn from. Operator optimization can come later. (Yes, I'm aware that I can start with a Turing machine and go from there. That's a bit extreme.) Edit: What I'm aiming for is akin to bootstrapping an operating system or a new compiler. What do I need do implement, at minimum, so that I can construct the rest of the system out of those primitive building blocks? I won't implement this on bare hardware; as an educational exercise, I'd write my own minimal VM.

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  • Algorithm for disordered sequences of strings

    - by Kinopiko
    The Levenshtein distance gives us a way to calculate the distance between two similar strings in terms of disordered individual characters: quick brown fox quikc brown fax The Levenshtein distance = 3. What is a similar algorithm for the distance between two strings with similar subsequences? For example, in quickbrownfox brownquickfox the Levenshtein distance is 10, but this takes no account of the fact that the strings have two similar subsequences, which makes them more "similar" than completely disordered words like quickbrownfox qburiocwknfox and yet the completely disordered version has a Levenshtein distance of eight. What distance measures exist which take the length of subsequences into account, without assuming that the subsequences can be easily broken into distinct words?

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  • ExpressionEngine: {exp:query} producing error

    - by Josh Brown
    Hi. I have this code in place to pull some relation data from the database based on a ID of another weblog entry. The relationship custom field would not work for my situation. I have tested the SQL with MySQL and get no errors. But I get an error when I pull up the page. {exp:query sql="SELECT entry_id,field_id_16,field_id_19 FROM exp_weblog_data WHERE field_id_15='2' AND weblog_id='6'"} Also, I want to populate the “field_id_15” from the url. I have tried using the “segment_*” tag, but nothing. Maybe it is something else. Any help is greatly appreciated. Thanks, Josh

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  • Algorithm for measuring distance between disordered sequences

    - by Kinopiko
    The Levenshtein distance gives us a way to calculate the distance between two similar strings in terms of disordered individual characters: quick brown fox quikc brown fax The Levenshtein distance = 3. What is a similar algorithm for the distance between two strings with similar subsequences? For example, in quickbrownfox brownquickfox the Levenshtein distance is 10, but this takes no account of the fact that the strings have two similar subsequences, which makes them more "similar" than completely disordered words like quickbrownfox qburiocwknfox and yet this completely disordered version has a Levenshtein distance of eight. What distance measures exist which take the length of subsequences into account, without assuming that the subsequences can be easily broken into distinct words?

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  • Codeigniter: Make field increase by 1 up to a number?

    - by Kevin Brown
    In my validation class I have this: $fields['a_1'] = 'First Question'; $fields['a_2'] = 'Second Question'; $fields['a_3'] = 'Third Question'; $fields['a_4'] = 'Fourth Question'; This is getting old--I have about 40 of these to write, and each set has matching validation rules: $rules['a_1'] = 'hour'; $rules['a_2'] = 'hour'; ... Is there a way to say: $fields['a_' . 1 - 17] = "One, Two" Etc... Just curious... if not, I'll brute force it.

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  • nHibernate persist IList<DayOfWeek>

    - by Charlie Brown
    Is it possible to persist an IList<DayOfWeek> using nHibernate? public class Vendor { public virtual IList<DayOfWeek> OrderDays { get; private set; } } If not, what are some common solutions; creating a class for OrderDays?, using an IList<string>?

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  • Python re.sub MULTILINE caret match

    - by cdleary
    The Python docs say: re.MULTILINE: When specified, the pattern character '^' matches at the beginning of the string and at the beginning of each line (immediately following each newline)... By default, '^' matches only at the beginning of the string... So what's going on when I get the following unexpected result? >>> import re >>> s = """// The quick brown fox. ... // Jumped over the lazy dog.""" >>> re.sub('^//', '', s, re.MULTILINE) ' The quick brown fox.\n// Jumped over the lazy dog.'

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  • Why does Font.registerFont throw an error the second time a swf is loaded?

    - by Al Brown
    I've found an issue (in flash cs5) when using TLFTextfields and fonts shared at runtime, and I wondered if anyone has a solution. Here's the scenario. Fonts.swf: library for fonts (runtime shared DF4) Popup.swf: popup with a TLFTextfield (with text in it) using a font from Fonts.swf Main.swf : the main swf with a button that loads and unloads Popup.swf (using Loader or SafeLoader give the same results) Nice and simple, Run main.swf, click button and the popup appears with the text. Click the button again to remove the popup. All well and good now click the button again and I get the following error. ArgumentError: Error #1508: The value specified for argument font is invalid. at flash.text::Font$/registerFont() at Popup_fla::MainTimeline()[Popup_fla.MainTimeline::MainTimeline:12] I'm presuming it's happening because the font is already registered (checked when clicking before the load). Does anyone know how to get past this? If you are wondering here's my Main.as package { import fl.controls.Button; import flash.display.Loader; import flash.display.Sprite; import flash.events.Event; import flash.events.IOErrorEvent; import flash.events.MouseEvent; import flash.events.UncaughtErrorEvent; import flash.net.URLRequest; import flash.text.Font; public class Main extends Sprite { public var testPopupBtn:Button; protected var loader:Loader; public function Main() { trace("Main.Main()"); testPopupBtn.label = "open"; testPopupBtn.addEventListener(MouseEvent.CLICK, testClickHandler); } protected function testClickHandler(event:MouseEvent):void { trace("Main.testClickHandler(event)"); if(loader) { testPopupBtn.label = "open"; this.removeChild(loader); //loader.unloadAndStop(); loader = null; }else{ testPopupBtn.label = "close"; trace("Registered Fonts -->"); var fonts:Array = Font.enumerateFonts(false); for each (var font:Font in fonts) { trace("\t",font.fontName, font.fontStyle, font.fontType); } trace("<--"); loader = new Loader(); loader.uncaughtErrorEvents.addEventListener(UncaughtErrorEvent.UNCAUGHT_ERROR, uncaughtErrorHandler); this.addChild(loader); try{ loader.load(new URLRequest("Popup.swf")); }catch(e:*){ trace(e); } } } private function uncaughtErrorHandler(event:UncaughtErrorEvent):void { trace("Main.uncaughtErrorHandler(event)", event); } } }

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  • Opening XNA Xbox 360 assemblies in Reflector

    - by David Brown
    I'd like to get a look at the differences between the Xbox 360 and Windows XNA assemblies. I know the 360 runs the .NET Compact Framework and I was under the impression that Reflector could read CF assemblies, but when I open them, all of the methods are blank and no internal classes are shown. Is this done on purpose, or is it a limitation of Reflector? Is there another way to see how the Xbox 360 XNA assemblies work?

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  • how to load an image to a grid using pygame, instead of just using a fill color?

    - by yao jiang
    I am trying to create a "map of a city" using pygame. I want to be able to put images of buildings in specific grid coords rather than just filling them in with a color. This is how I am creating this map grid: def clear(): for r in range(rows): for c in range(rows): if r%3 == 1 and c%3 == 1: color = brown; grid[r][c] = 1; else: color = white; grid[r][c] = 0; pygame.draw.rect(screen, color, [(margin+width)*c+margin, (margin+height)*r+margin, width, height]) pygame.display.flip(); Now how do I put images of buildings in those brown colored grids at those specific locations? I've tried some of the samples online but can't seem to get them to work. Any help is appreciated. If anyone have a good source for free sprites that I can use for pygame, please let me know. Thanks!

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  • Algorithm for measuring distance between disordered sequences of strings

    - by Kinopiko
    The Levenshtein distance gives us a way to calculate the distance between two similar strings in terms of disordered individual characters: quick brown fox quikc brown fax The Levenshtein distance = 3. What is a similar algorithm for the distance between two strings with similar subsequences? For example, in quickbrownfox brownquickfox the Levenshtein distance is 10, but this takes no account of the fact that the strings have two similar subsequences, which makes them more "similar" than completely disordered words like quickbrownfox qburiocwknfox and yet this completely disordered version has a Levenshtein distance of eight. What distance measures exist which take the length of subsequences into account, without assuming that the subsequences can be easily broken into distinct words?

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  • A JTAG emulator for use with a Hawkboard and OpenOCD?

    - by David Brown
    I'd like to try bare metal ARM programming with the Hawkboard, but the deployment process looks awful. I'm totally new to this, so I could be misunderstanding the instructions, but it appears that I have to use a program called AISgen to convert the binary file, then boot with u-Boot over UART and copy the AIS binary into memory. Not only is that a lot of stuff to do every time I make a change, it also doesn't give me the ability to debug with GDB. The best solution for this that I can find is JTAG. But the prices for these JTAG emulators look ridiculous. I'm not even sure which ones will work with the Hawkboard and which ones won't. So far, my best bet appears to be the Flyswatter, but the pin layout is different. Basically, I need something that's relatively cheap and works with the Hawkboard and OpenOCD. Any suggestions? Or is there another way I could do this, perhaps?

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  • Update panel and usercontrols

    - by Charlie Brown
    I have two web user controls nested inside of an update panel. The events inside the user controls do not appear to trigger the panel. For testing, I have set the method the fires to sleep for 3 seconds, and added an update progress panel to the page. The update progress panel never comes up and the page reflashes as usual. The user controls work correctly and do what they need to do, but I would like to make them ajaxy and pretty. Is there a special method for adding usercontrols to an update so the postback works correctly? <asp:ScriptManager ID="ScriptManager1" runat="server"> </asp:ScriptManager> <asp:UpdateProgress ID="UpdateProgress1" runat="server" DisplayAfter="100"> <ProgressTemplate> UPDATING...</ProgressTemplate> </asp:UpdateProgress> <asp:UpdatePanel ID="UpdatePanel1" runat="server"> <ContentTemplate> <div id="order"> <keg:BeerList runat="server" ID="uxBeerList" /> <kegcart:ShoppingCart runat="server" ID="uxCustomerCart" /> <br class="clearfloat" /> </div> </ContentTemplate> </asp:UpdatePanel> Protected Sub uxBeerList_AddItem(ByVal item As KegData.IOrderableItem) Handles uxBeerList.AddItem uxCustomerCart.AddItemToOrder(item) System.Threading.Thread.Sleep(5000) End Sub

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  • Codeigniter: Using URIs with forms

    - by Kevin Brown
    I'm using URIs to direct a function in a library: $id = $this->CI->session->userdata('id'); $URI = $this->CI->uri->uri_string(); $new = "new"; if(strpos($URI, $new) === FALSE){ $method = "update"; } elseif(strpos($URI, $new) !== FALSE){ $method = "create"; } So I have two if statements directing what information to if ($method === 'update') { // Modify form, first load $this->CI->db->from('be_survey'); $this->CI->db->where('user_id' , $id); $survey = $this->CI->db->get(); $user = array_merge($user->row_array(),$survey->row_array()); $this->CI->validation->set_default_value($user); // Display page $data['user'] = $user; } $this->CI->validation->set_rules($rules); if ( $this->CI->validation->run() === FALSE ) { // Output any errors $this->CI->validation->output_errors(); } else { // Submit form $this->_submit($method); } Submit function: function _submit($method) { //Submit and Update for current User $id = $this->CI->session->userdata('id'); $this->CI->db->select('users.id, users.username, users.email, profiles.firstname, profiles.manager_id'); $this->CI->db->from('be_users' . " users"); $this->CI->db->join('be_user_profiles' . " profiles",'users.id=profiles.user_id'); $this->CI->db->having('id', $id); $email_data['user'] = $this->CI->db->get(); $email_data['user'] = $email_data['user']->row(); $manager_id = $email_data['user']->manager_id; $this->CI->db->select('firstname','email')->from('be_user_profiles')->where('user_id', $manager_id); $email_data['manager'] = $this->CI->db->get(); $email_data['manager'] = $email_data['manager']->row(); // Fetch what they entered in the form for($i=1;$i<18;$i++){ $survey["a_".$i]= $this->CI->input->post('a_'.$i); } for($i=1;$i<15;$i++){ $survey["b_".$i]= $this->CI->input->post('b_'.$i); } for($i=1;$i<12;$i++){ $survey["c_".$i]= $this->CI->input->post('c_'.$i); } $profile['firstname'] = $this->CI->input->post('firstname'); $profile['lastname'] = $this->CI->input->post('lastname'); $profile['test_date'] = date ("Y-m-d H:i:s"); $profile['company_name'] = $this->CI->input->post('company_name'); $profile['company_address'] = $this->CI->input->post('company_address'); $profile['company_city'] = $this->CI->input->post('company_city'); $profile['company_phone'] = $this->CI->input->post('company_phone'); $profile['company_state'] = $this->CI->input->post('company_state'); $profile['company_zip'] = $this->CI->input->post('company_zip'); $profile['job_title'] = $this->CI->input->post('job_title'); $profile['job_type'] = $this->CI->input->post('job_type'); $profile['job_time'] = $this->CI->input->post('job_time'); $profile['department'] = $this->CI->input->post('department'); $profile['vision'] = $this->CI->input->post('vision'); $profile['height'] = $this->CI->input->post('height'); $profile['weight'] = $this->CI->input->post('weight'); $profile['hand_dominance'] = $this->CI->input->post('hand_dominance'); $profile['areas_of_fatigue'] = $this->CI->input->post('areas_of_fatigue'); $profile['job_description'] = $this->CI->input->post('job_description'); $profile['injury_review'] = $this->CI->input->post('injury_review'); $profile['job_positive'] = $this->CI->input->post('job_positive'); $profile['risk_factors'] = $this->CI->input->post('risk_factors'); $profile['job_improvement_short'] = $this->CI->input->post('job_improvement_short'); $profile['job_improvement_long'] = $this->CI->input->post('job_improvement_long'); if ($method == "update") { //Begin db transmission $this->CI->db->trans_begin(); $this->CI->home_model->update('Survey',$survey, array('user_id' => $id)); $this->CI->db->update('be_user_profiles',$profile, array('user_id' => $id)); if ($this->CI->db->trans_status() === FALSE) { flashMsg('error','There was a problem entering your test! Please contact an administrator.'); redirect('survey','location'); } else { //Get credits of user and subtract 1 $this->CI->db->set('credits', 'credits -1', FALSE); $this->CI->db->update('be_user_profiles',$profile, array('user_id' => $manager_id)); //Mark the form completed. $this->CI->db->set('test_complete', '1'); $this->CI->db->where('user_id', $id)->update('be_user_profiles'); // Stuff worked... $this->CI->db->trans_commit(); //Get Manager Information $this->CI->db->select('users.id, users.username, users.email, profiles.firstname'); $this->CI->db->from('be_users' . " users"); $this->CI->db->join('be_user_profiles' . " profiles",'users.id=profiles.user_id'); $this->CI->db->having('id', $email_data['user']->manager_id); $email_data['manager'] = $this->CI->db->get(); $email_data['manager'] = $email_data['manager']->row(); //Email User $this->CI->load->library('User_email'); $data_user = array( 'firstname'=>$email_data['user']->firstname, 'email'=> $email_data['user']->email, 'user_completed'=>$email_data['user']->firstname, 'site_name'=>$this->CI->preference->item('site_name'), 'site_url'=>base_url() ); //Email Manager $data_manager = array( 'firstname'=>$email_data['manager']->firstname, 'email'=> $email_data['manager']->email, 'user_completed'=>$email_data['user']->firstname, 'site_name'=>$this->CI->preference->item('site_name'), 'site_url'=>base_url() ); $this->CI->user_email->send($email_data['manager']->email,'Completed the Assessment Tool','public/email_manager_complete',$data_manager); $this->CI->user_email->send($email_data['user']->email,'Completed the Assessment Tool','public/email_user_complete',$data_user); flashMsg('success','You finished the assessment successfully!'); redirect('home','location'); } } //Create New User elseif ($method == "create") { // Build $profile['user_id'] = $id; $profile['manager_id'] = $manager_id; $profile['test_complete'] = '1'; $survey['user_id'] = $id; $this->CI->db->trans_begin(); // Add user_profile details to DB $this->CI->db->insert('be_user_profiles',$profile); $this->CI->db->insert('be_survey',$survey); if ($this->CI->db->trans_status() === FALSE) { // Registration failed $this->CI->db->trans_rollback(); flashMsg('error',$this->CI->lang->line('userlib_registration_failed')); redirect('auth/register','location'); } else { // User registered $this->CI->db->trans_commit(); flashMsg('success',$this->CI->lang->line('userlib_registration_success')); redirect($this->CI->config->item('userlib_action_register'),'location'); } } } The submit function is similar, updating the db if $method == "update", and inserting if the method == "create". The problem is, when the form is submitted, it doesn't take into account the url b/c the form submits to the function "survey", which passes data to the lib function, so things are always updated, never created. *How can I pass $method to the _submit() function correctly?!*

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  • Threading extra state through a parser in Scala

    - by Travis Brown
    I'll give you the tl;dr up front I'm trying to use the state monad transformer in Scalaz 7 to thread extra state through a parser, and I'm having trouble doing anything useful without writing a lot of t m a -> t m b versions of m a -> m b methods. An example parsing problem Suppose I have a string containing nested parentheses with digits inside them: val input = "((617)((0)(32)))" I also have a stream of fresh variable names (characters, in this case): val names = Stream('a' to 'z': _*) I want to pull a name off the top of the stream and assign it to each parenthetical expression as I parse it, and then map that name to a string representing the contents of the parentheses, with the nested parenthetical expressions (if any) replaced by their names. To make this more concrete, here's what I'd want the output to look like for the example input above: val target = Map( 'a' -> "617", 'b' -> "0", 'c' -> "32", 'd' -> "bc", 'e' -> "ad" ) There may be either a string of digits or arbitrarily many sub-expressions at a given level, but these two kinds of content won't be mixed in a single parenthetical expression. To keep things simple, we'll assume that the stream of names will never contain either duplicates or digits, and that it will always contain enough names for our input. Using parser combinators with a bit of mutable state The example above is a slightly simplified version of the parsing problem in this Stack Overflow question. I answered that question with a solution that looked roughly like this: import scala.util.parsing.combinator._ class ParenParser(names: Iterator[Char]) extends RegexParsers { def paren: Parser[List[(Char, String)]] = "(" ~> contents <~ ")" ^^ { case (s, m) => (names.next -> s) :: m } def contents: Parser[(String, List[(Char, String)])] = "\\d+".r ^^ (_ -> Nil) | rep1(paren) ^^ ( ps => ps.map(_.head._1).mkString -> ps.flatten ) def parse(s: String) = parseAll(paren, s).map(_.toMap) } It's not too bad, but I'd prefer to avoid the mutable state. What I want Haskell's Parsec library makes adding user state to a parser trivially easy: import Control.Applicative ((*>), (<$>), (<*)) import Data.Map (fromList) import Text.Parsec paren = do (s, m) <- char '(' *> contents <* char ')' h : t <- getState putState t return $ (h, s) : m where contents = flip (,) [] <$> many1 digit <|> (\ps -> (map (fst . head) ps, concat ps)) <$> many1 paren main = print $ runParser (fromList <$> paren) ['a'..'z'] "example" "((617)((0)(32)))" This is a fairly straightforward translation of my Scala parser above, but without mutable state. What I've tried I'm trying to get as close to the Parsec solution as I can using Scalaz's state monad transformer, so instead of Parser[A] I'm working with StateT[Parser, Stream[Char], A]. I have a "solution" that allows me to write the following: import scala.util.parsing.combinator._ import scalaz._, Scalaz._ object ParenParser extends ExtraStateParsers[Stream[Char]] with RegexParsers { protected implicit def monadInstance = parserMonad(this) def paren: ESP[List[(Char, String)]] = (lift("(" ) ~> contents <~ lift(")")).flatMap { case (s, m) => get.flatMap( names => put(names.tail).map(_ => (names.head -> s) :: m) ) } def contents: ESP[(String, List[(Char, String)])] = lift("\\d+".r ^^ (_ -> Nil)) | rep1(paren).map( ps => ps.map(_.head._1).mkString -> ps.flatten ) def parse(s: String, names: Stream[Char]) = parseAll(paren.eval(names), s).map(_.toMap) } This works, and it's not that much less concise than either the mutable state version or the Parsec version. But my ExtraStateParsers is ugly as sin—I don't want to try your patience more than I already have, so I won't include it here (although here's a link, if you really want it). I've had to write new versions of every Parser and Parsers method I use above for my ExtraStateParsers and ESP types (rep1, ~>, <~, and |, in case you're counting). If I had needed to use other combinators, I'd have had to write new state transformer-level versions of them as well. Is there a cleaner way to do this? I'd love to see an example of a Scalaz 7's state monad transformer being used to thread state through a parser, but Scala 6 or Haskell examples would also be useful.

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