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  • Flex : providing data with a PHP Class

    - by Tristan
    Hello, i'm a very new user to flex (never use flex, nor flashbuilder, nor action script before), but i want to learn this langage because of the beautiful RIA and chart it can do. I watched the video on adobe : 1 hour to build your first program but i'm stuck : On the video it says that we have to provide a PHP class for accessing data and i used the example that flash builder gave (with zend framework and mysqli). I never used those ones and it makes a lot to learn if i count zen + mysqli. My question is : can i use a PHP class like this one ? What does flash builder except in return ? i hear that was automatic. example it may be wrong, i'm not very familiar with classes when acessing to database : <?php class DBConnection { protected $server = "localhost"; protected $username = "root"; protected $password = "root"; protected $dbname = "something"; protected $connection; function __construct() { $this->connection = mysql_connect($this->server, $this->username, $this->password); mysql_select_db($this->dbname,$this->connection); mysql_query("SET NAMES 'utf8'", $this->connection); } function query($query) { $result = mysql_query($query, $this->connection); if (!$result) { echo 'request error ' . mysql_error($this->connection); exit; } return $result; } function getAll() { $req = "select * from servers"; $result = query($req) return $result } function num_rows() { return mysql_num_rows($result); } function end() { mysql_close($this->connection); } } ?> Thank you,

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  • Contingent Header Category Label

    - by poindexter
    Right now the header has a bit of code in it that queries the section name and then uses that section name as the h1 title in the page. It works fine. However, I want to selectively break that operation in certain categories and give myself the ability to manually enter the h1 title for a given section. Here's what I'm struggling with: how can I maintain the automatic query and title selection in most instances, but selectively break it in a given category (the 'blog' category, for starters)? Thanks for taking a look, I appreciate your help! Here's the code that drives the existing function (it's the get_the_section_name part): <?php if(!is_home()){?> <div class="section <?php echo get_the_section_name();?>"> <?php $sectitle = get_the_section_name(); $sectitle = str_ireplace("-"," ",$sectitle); echo '<h1>' . $sectitle . '</h1>';?> <p class="breadcrumbs"> <?php if(function_exists('bcn_display')) { bcn_display(); } ?> </p> </div> <div class="columns"> <?php } ?> Here's a page that shows what it looks like displayed (see the title in the blue graphic underneath the main nav near the top of the page): http://69.20.59.228/category/blog/

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  • NSTableView selection & highlights

    - by Christian
    I have a NSTableView as a very central part of my Application and want it to integrate more with the rest of it. It has only one column (it's a list) and I draw all Cells (normal NSTextFieldCells) myself. The first problem is the highlighting. I draw the highlight myself and want to get rid of the blue background. I now fill the whole cell with the original background color to hide the blue background, but this looks bad when dragging the cell around. I tried overriding highlight:withFrame:inView: and highlightColorWithFrame:inView: of NSCell but nothing happened. How can I disable automatic highlighting? I also want all rows/cells to be deselected when I click somewhere outside my NSTableView. Since the background / highlight of the selected cell turns gray there must be an event for this, but I can't find it. I let my cells expand on a double click and may need to undo this. So getting rid of the gray highlight is not enough. EDIT: I add a subview to the NSTableView when a cell gets double clicked and then resignFirstResponder of the NSTableView gets called. I tried this: - (BOOL)resignFirstResponder { if (![[self subviews] containsObject:[[self window] firstResponder]]) { [self deselectAll:self]; ... } return YES; } Besides that it's not working I would need to implement this method for all objects in the view hierarchy. Is there an other solution to find out when the first responder leaves a certain view hierarchy?

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  • Forces to prompt download box IE

    - by Bruno Costa
    Hello, I'm having a problem with some reports in the application I'm doing manutention I've a button that does a postback to the server and do some information and then get back to the cliente and open a popup to download the report. private void grid_ItemCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e) { ... ClientScript.RegisterClientScriptBlock(this.GetType(), "xxx", "<script>javascript:window.location('xx.aspx?m=x','xxx','width=750,height=350,directories=no,location=no,menubar=no,scrollbars,status=no,toolbar=no,resizable=yes,left=50,top=50');</script>"); } Then in xxx.aspx I've the code: Response.ClearContent(); Response.ClearHeaders(); Response.TransmitFile(tempFileName); Response.Flush(); Response.Close(); File.Delete(tempFileName); Response.End(); This works fine if IE option Automatic prompting for file downloads is enabled. But by default this is disabled and I need to force the download box to be prompting. Can I do anything without change a lot of code? Thanks.

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  • Best source control system for maintaining different versions

    - by dalecooper
    Hi all! We need to be able to simultanously maintain a set of different versions of our system. I assume this is best done using branching. We currently use TFS2008 for source control, work items and automatic builds. What is the best version control solution for this task? Our organization is in the process of merging to TFS2010. Will TFS2010 give us the functionality we need to easily manage a series of branches per system version. We need to be able to keep each version isolated from the others, so that we can do testing deployment for each version. Our dev team consists of 5 .net developers and two flash developers. I have heard a lot of talk about GIT. Should we consider using GIT instead of TFS for source control? Is it possible to use TFS2010 together with GIT? Does anyone have similar setups that works nicely? Any sugggestions are appreciated! Thanks, Kjetil.

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  • Should not a tail-recursive function also be faster?

    - by Balint Erdi
    I have the following Clojure code to calculate a number with a certain "factorable" property. (what exactly the code does is secondary). (defn factor-9 ([] (let [digits (take 9 (iterate #(inc %) 1)) nums (map (fn [x] ,(Integer. (apply str x))) (permutations digits))] (some (fn [x] (and (factor-9 x) x)) nums))) ([n] (or (= 1 (count (str n))) (and (divisible-by-length n) (factor-9 (quot n 10)))))) Now, I'm into TCO and realize that Clojure can only provide tail-recursion if explicitly told so using the recur keyword. So I've rewritten the code to do that (replacing factor-9 with recur being the only difference): (defn factor-9 ([] (let [digits (take 9 (iterate #(inc %) 1)) nums (map (fn [x] ,(Integer. (apply str x))) (permutations digits))] (some (fn [x] (and (factor-9 x) x)) nums))) ([n] (or (= 1 (count (str n))) (and (divisible-by-length n) (recur (quot n 10)))))) To my knowledge, TCO has a double benefit. The first one is that it does not use the stack as heavily as a non tail-recursive call and thus does not blow it on larger recursions. The second, I think is that consequently it's faster since it can be converted to a loop. Now, I've made a very rough benchmark and have not seen any difference between the two implementations although. Am I wrong in my second assumption or does this have something to do with running on the JVM (which does not have automatic TCO) and recur using a trick to achieve it? Thank you.

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  • Kohana Sessions data does not persist across pages in chrome and ir browsers

    - by user1062637
    Kohana Session data does not persist across pages opened in Chrome and IE browsers the same works fine in a Firefox browser Kohana version used is 2.3 session config files hold $config['driver'] = 'native'; /** * Session storage parameter, used by drivers. */ $config['storage'] = ''; /** * Session name. * It must contain only alphanumeric characters and underscores. At least one letter must be present. */ $config['name'] = 'NITWSESSID'; /** * Session parameters to validate: user_agent, ip_address, expiration. */ $config['validate'] = array(); /** * Enable or disable session encryption. * Note: this has no effect on the native session driver. * Note: the cookie driver always encrypts session data. Set to TRUE for stronger encryption. */ $config['encryption'] = FALSE; /** * Session lifetime. Number of seconds that each session will last. * A value of 0 will keep the session active until the browser is closed (with a limit of 24h). */ $config['expiration'] = 2700; /** * Number of page loads before the session id is regenerated. * A value of 0 will disable automatic session id regeneration. */ $config['regenerate'] = 0; /** * Percentage probability that the gc (garbage collection) routine is started. */ $config['gc_probability'] = 2; Help needed urgently

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  • Still don't understand file upload-folder permissions

    - by Camran
    I have checked out articles and tutorials. I don't know what to do about the security of my picture upload-folder. It is pictures for classifieds which should be uploaded to the folder. This is what I want: Anybody may upload images to the folder. The images will be moved to another folder, by another php-code later on (automatic). Only I may manually remove them, as well as another php file on the server which automatically empties the folder after x-days. What should I do here? The images are uploaded via a php-upload script. This script checks to see if the extension of the file is actually a valid image-file. When I try this: chmod 755 images the images wont be uploaded. But like this it works: chmod 777 images But 777 is a security risk right? Please give me detailed information... The Q is, what to do to solve this problem, not info about what permissions there are etc etc... Thanks If you need more info let me know...

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  • NoSQL for filesystem storage organization and replication?

    - by wheaties
    We've been discussing design of a data warehouse strategy within our group for meeting testing, reproducibility, and data syncing requirements. One of the suggested ideas is to adapt a NoSQL approach using an existing tool rather than try to re-implement a whole lot of the same on a file system. I don't know if a NoSQL approach is even the best approach to what we're trying to accomplish but perhaps if I describe what we need/want you all can help. Most of our files are large, 50+ Gig in size, held in a proprietary, third-party format. We need to be able to access each file by a name/date/source/time/artifact combination. Essentially a key-value pair style look-up. When we query for a file, we don't want to have to load all of it into memory. They're really too large and would swamp our server. We want to be able to somehow get a reference to the file and then use a proprietary, third-party API to ingest portions of it. We want to easily add, remove, and export files from storage. We'd like to set up automatic file replication between two servers (we can write a script for this.) That is, sync the contents of one server with another. We don't need a distributed system where it only appears as if we have one server. We'd like complete replication. We also have other smaller files that have a tree type relationship with the Big files. One file's content will point to the next and so on, and so on. It's not a "spoked wheel," it's a full blown tree. We'd prefer a Python, C or C++ API to work with a system like this but most of us are experienced with a variety of languages. We don't mind as long as it works, gets the job done, and saves us time. What you think? Is there something out there like this?

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  • Interpolating data points in Excel

    - by Niels Basjes
    Hi, I'm sure this is the kind of problem other have solved many times before. A group of people are going to do measurements (Home energy usage to be exact). All of them will do that at different times and in different intervals. So what I'll get from each person is a set of {date, value} pairs where there are dates missing in the set. What I need is a complete set of {date, value} pairs where for each date withing the range a value is known (either measured or calculated). I expect that a simple linear interpolation would suffice for this project. If I assume that it must be done in Excel. What is the best way to interpolate in such a dataset (so I have a value for every day) ? Thanks. NOTE: When these datasets are complete I'll determine the slope (i.e. usage per day) and from that we can start doing home-to-home comparisons. ADDITIONAL INFO After first few suggestions: I do not want to manually figure out where the holes are in my measurement set (too many incomplete measurement sets!!). I'm looking for something (existing) automatic to do that for me. So if my input is {2009-06-01, 10} {2009-06-03, 20} {2009-06-06, 110} Then I expect to automatically get {2009-06-01, 10} {2009-06-02, 15} {2009-06-03, 20} {2009-06-04, 50} {2009-06-05, 80} {2009-06-06, 110} Yes, I can write software that does this. I am just hoping that someone already has a "ready to run" software (Excel) feature for this (rather generic) problem.

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  • Fetching just the Key/id from a ReferenceProperty in App Engine

    - by ozone
    Hi SO, I could use a little help in AppEngine land... Using the [Python] API I create relationships like this example from the docs: class Author(db.Model): name = db.StringProperty() class Story(db.Model): author = db.ReferenceProperty(Author) story = db.get(story_key) author_name = story.author.name As I understand it, that example will make two datastore queries. One to fetch the Story and then one to deference the Author inorder to access the name. But I want to be able to fetch the id, so do something like: story = db.get(story_key) author_id = story.author.key().id() I want to just get the id from the reference. I do not want to have to deference (therefore query the datastore) the ReferenceProperty value. From reading the documentation it says that the value of a ReferenceProperty is a Key Which leads me to think that I could just call .id() on the reference's value. But it also says: The ReferenceProperty model provides features for Key property values such as automatic dereferencing. I can't find anything that explains when this referencing takes place? Is it safe to call .id() on the ReferenceProperty's value? Can it be assumed that calling .id() will not cause a datastore lookup?

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  • ASP.net MVC Linq-To-SQL Many-To-Many Field Binding

    - by user336858
    Hi there, The short version of this question is "Is there a way to gracefully handle database insertion for an object that has a many-to-many field that has been set up in a partial class?" Apologies if it's been asked before. Example Suppose I have a typical MVC setup with the tables: Posts {PostID, ...} Categories {CategoryID, ...} A post can have more than one category, and a category can identify more than one post. Thus suppose further that I need an extra table: PostCategories {PostID, CategoryID, ...} This handles the many-to-many relationship between posts and categories. As far as I know, there's no way to do this in Linq-to-SQL right now so I have to shoehorn it in by adding a partial Post class to the project to add that functionality. Something like: public partial class Post { public IEnumerable<Category> Categories{ get { ... } set { ... } } } So I can now create a "Create" view that automatically populates a "Categories" UI item. This is where the trouble starts. So here's my question: How do you get automatic object model binding to work cleanly with an object that has a many-to-many relationship to control? The workaround that makes many-to-many relationships possible relies on the Post object having a PostID in order to be associated with CategoryID(s), which is only issued after the Post object has been submitted for validation and insertion. Bit of a Catch22 here. Any terminology, links, or tips you can provide would be tremendously helpful!

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  • How to encapsulate a third party complex object structure?

    - by tangens
    Motivation Currently I'm using the java parser japa to create an abstract syntax tree (AST) of a java file. With this AST I'm doing some code generation (e.g.: if there's an annotation on a method, create some other source files, ...) Problem When my code generation becomes more complex, I've to dive deeper into the structure of the AST (e.g. I have to use visitors to extract some type information of method parameters). But I'm not sure if I want to stay with japa or if I will change the parser library later. Because my code generator uses freemarker (which isn't good at automatic refactoring) I want the interface that it uses to access the AST information to be stable, even if I decide to change the java parser. Question What's the best way to encapsulate complex datastructures of third party libraries? I could create my own datatypes and copy the parts of the AST that I need into these. I could create lots of specialized access methods that work with the AST and create exactly the infos I need (e.g. the fully qualified return type of a method as one string, or the first template parameter of a class). I could create wrapper classes for the japa datastructures I currently need and embed the japa types inside, so that I can delegate requests to the japa types and transform the resulting japa types to my wrapper classes again. Which solution should I take? Are there other (better) solutions to this problem?

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  • Asp MVC - "The Id field is required" validation message on Create; Id not set to [Required]

    - by Dann
    This is happening when I try to create the entity using a Create style action in Asp.Net MVC 2. The POCO has the following properties: public int Id {get;set;} [Required] public string Message {get; set} On the creation of the entity, the Id is set automatically, so there is no need for it on the Create action. The ModelState says that "The Id field is required", but I haven't set that to be so. Is there something automatic going on here? EDIT - Reason Revealed The reason for the issue is answered by Brad Wilson via Paul Speranza in one of the comments below where he says (cheers Paul): You're providing a value for ID, you just didn't know you were. It's in the route data of the default route ("{controller}/{action}/{id}"), and its default value is the empty string, which isn't valid for an int. Use the [Bind] attribute on your action parameter to exclude ID. My default route was: new { controller = "Customer", action = "Edit", id = " " } // Parameter defaults EDIT - Update Model technique I actually changed the way I did this again by using TryUpdateModel and the exclude parameter array asscoiated with that. [HttpPost] public ActionResult Add(Venue collection) { Venue venue = new Venue(); if (TryUpdateModel(venue, null, null, new[] { "Id" })) { _service.Add(venue); return RedirectToAction("Index", "Manage"); } return View(collection); }

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  • Sizing issues while adding a .Net UserControl to a TabPage

    - by TJ_Fischer
    I have a complex Windows Forms GUI program that has a lot of automated control generation and manipulation. One thing that I need to be able to do is add a custom UserControl to a newly instatiated TabPage. However, when my code does this I get automatic resizing events that cause the formatting to get ugly. Without detailing all of the different Containers that could possibly be involved, the basic issue is this: At a certain point in the code I create a new tab page: TabPage tempTabPage = new TabPage("A New Tab Page"); Then I set it to a certain size that I want it to maintain: tempTabPage.Width = 1008; tempTabPage.Height = 621; Then I add it to a TabControl: tabControl.TabPages.Add(tempTabPage); Then I create a user control that I want to appear in the newly added TabPage: CustomView customView = new CustomView("A new custom control"); Here is where the problem comes in. At this point both the tempTabPage and the customView are the same size with no padding or margin and they are the size I want them to be. I now try to add this new custom UserControl to the tab page like this: tempTabPage.Controls.Add(customView); When making this call the customView and it's children controls get resized to be larger and so parts of the customView are hidden. Can anyone give me any direction on what to look for or what could be causing this kind of issue? Thanks ahead of time.

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  • Programmatically configure MATLAB

    - by Richie Cotton
    Since MathWorks release a new version of MATLAB every six months, it's a bit of hassle having to set up the latest version each time. What I'd like is an automatic way of configuring MATLAB, to save wasting time on administrative hassle. The sorts of things I usually do when I get a new version are: Add commonly used directories to the path. Create some toolbar shortcuts. Change some GUI preferences. The first task is easy to accomplish programmatically with addpath and savepath. The next two are not so simple. Details of shortcuts are stored in the file 'shortcuts.xml' in the folder given by prefdir. My best idea so far is to use one of the XML toolboxes in the MATLAB Central File Exchange to read in this file, add some shortcut details and write them back to file. This seems like quite a lot of effort, and that usually means I've missed an existing utility function. Is there an easier way of (programmatically) adding shortcuts? Changing the GUI preferences seems even trickier. preferences just opens the GUI preference editor (equivalent to File - Preferences); setpref doesn't seems to cover GUI options. The GUI preferences are stored in matlab.prf (again in prefdir); this time in traditional name=value config style. I could try overwriting values in this directly, but it isn't always clear what each line does, or how much the names differ between releases, or how broken MATLAB will be if this file contains dodgy values. I realise that this is a long shot, but are the contents of matlab.prf documented anywhere? Or is there a better way of configuring the GUI? For extra credit, how do you set up your copy of MATLAB? Are there any other tweaks I've missed, that it is possible to alter via a script?

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  • Native Endians and Auto Conversion

    - by KnickerKicker
    so the following converts big endians to little ones uint32_t ntoh32(uint32_t v) { return (v << 24) | ((v & 0x0000ff00) << 8) | ((v & 0x00ff0000) >> 8) | (v >> 24); } works. like a charm. I read 4 bytes from a big endian file into char v[4] and pass it into the above function as ntoh32 (* reinterpret_cast<uint32_t *> (v)) that doesn't work - because my compiler (VS 2005) automatically converts the big endian char[4] into a little endian uint32_t when I do the cast. AFAIK, this automatic conversion will not be portable, so I use uint32_t ntoh_4b(char v[]) { uint32_t a = 0; a |= (unsigned char)v[0]; a <<= 8; a |= (unsigned char)v[1]; a <<= 8; a |= (unsigned char)v[2]; a <<= 8; a |= (unsigned char)v[3]; return a; } yes the (unsigned char) is necessary. yes it is dog slow. there must be a better way. anyone ?

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  • Classify data (cell array) based on years in MATLAB

    - by user2991243
    Suppose that we have this cell array of data : a={43 432 2006; 254 12 2008; 65 35 2000; 64 34 2000; 23 23 2006; 64 2 2010; 32 5 2006; 22 2 2010} Last column of this cell array is years. I want classify data(rows) based on years like this : a_2006 = {43 432 2006; 32 5 2006; 32 5 2006} a_2008 = {254 12 2008}; a_2000 = {65 35 2000; 64 34 2000} a_2010 = {64 2 2010; 22 2 2010} I have different years in column three in every cell array (this cell array is a sample) so I want an automatic method to determine the years and classify them to a_yearA , a_yearB etc. or other naming that I can distinguish years and call data years easily. How can I do this? Thanks.da

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  • Foreign key relationships in Entity Framework

    - by Anders Svensson
    I'm trying to add an object created from Entity Data Model classes. I have a table called Users, which has turned into a User EDM class. And I also have a table Pages, which has become a Page EDM class. These tables have a foreign key relationship, so that each page is associated with many users. Now I want to be able to add a page, but I can't get how to do it. I get a nullreference exception on Users below. I'm still rather confused by all this, so I'm sure it's a simple error, but I just can't see how to do it. Also, by the way, the compiler requires that I set PageID in the object initializer, even though this field is set to be an automatic id in the table. Am I doing it right just setting it to 0, expecting it to be updated automatically in the table when saved, or how should I do that? Any help appreciated! The method in question: private Page GetPage(User currentUser) { string url = _request.ServerVariables["url"].ToLower(); var userPages = from p in _context.PageSet where p.Users.UserID == currentUser.UserID select p; var existingPage = userPages.FirstOrDefault(e => e.Url == url); //Could be combined with above, but hard to read? if (existingPage != null) return existingPage; Page page = new Page() { Count = 0, Url = _request.ServerVariables["url"].ToLower(), PageID = 0, //Only initial value, changed later? }; _context.AddToPageSet(page); page.Users.UserID = currentUser.UserID; //Here's the problem... return page; }

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  • Convincing why testing is good

    - by FireAphis
    Hello, In my team of real-time-embedded C/C++ developers, most people don't have any culture of testing their code beyond the casual manual sanity checks. I personally strongly believe in advantages of autonomous automatic tests, but when I try to convince I get some reappearing arguments like: We will spend more time on writing the tests than writing the code. It takes a lot of effort to maintain the tests. Our code is spaghetti; no way we can unit-test it. Our requirement are not sealed – we’ll have to rewrite all the tests every time the requirements are changed. Now, I'd gladly hear any convincing tips and advises, but what I am really looking for are references to researches, articles, books or serious surveys that show (preferably in numbers) how testing is worth the effort. Something like "We in IBM/Microsoft/Google, surveying 3475 active projects, found out that putting 50% more development time into testing decreased by 75% the time spent on fixing bugs" or "after half a year, the time needed to write code with test was only marginally longer than what used to take without tests". Any ideas? P.S.: I'm adding C++ tag too in case someone has a specific experience with convincing this, usually elitist, type of developers :-)

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  • How can I restore the "auto" values with for list-style-type in nested unordered lists with CSS?

    - by Michael
    By default, an unstyled set of nested <ul> lists looks like this (in Chrome, Firefox, and IE at least): The top level has a list-style-type of disc, the next level is circle, and subsequent levels are square. If I include a stylesheet that changes the list-style-type to none, is there a simple way to revert back to the "automatic bullet types" later in the document? (e.g., override with a subsequent CSS definition or JavaScript style change) Basically, I'm looking for something like list-style-type: auto; (which is apparently not valid and has no effect): <style type="text/css"> ul { list-style-type: none; } ul { list-style-type: auto; } /* Does not work */ </style> Setting the list-style-type back to disc changes every bullet in the list and I no longer see different bullets at different levels, so that doesn't work either. Is the only way to accomplish this by explicitly defining styles for every level? e.g.: <style type="text/css"> ul { list-style-type: disc; } ul ul { list-style-type: circle; } ul ul ul { list-style-type: square; } </style>

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  • Ideas for storing e-mail messages in a Delphi client server application

    - by user193655
    There are many suggestions here and there for storing e-mail messages. Somehow what I am doing is writing an Outlook addin to send emails from inbox/sent folders directly to my application. So only what is really interesting is saved. And I decide where to save it. Imagine this case: I recieve an email from a customer. It's up to me to decide whether I should save it on the customer or on the order 24 that that customer did. So this is why I am doing the add in, and not some automatic storing of emails = noise after some time. This said, how to store the emails? For the emails that I recieve or send through Outlook the idea could be save the whole file in a blob field (so the eml file), may be I can save also other info (like the subject) in another text field. But the problem comes when I write an email from my application. In this case I am not generating an eml file, I send through MAPI data to Outlook to compose an email that I will send with Outlook (so in this case I cannot save the eml), or I directly send it with Indy. Also in this case I don't have the eml file... One idea could be that the all the emails that I auto compose have a special flag that the Add in recognises and therefore when I send the mail it is stored back to the DB. So in this case I can save the eml also of the mails I sent from my application. May you comment?

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  • Appropriate uses of Monad `fail` vs. MonadPlus `mzero`

    - by jberryman
    This is a question that has come up several times for me in the design code, especially libraries. There seems to be some interest in it so I thought it might make a good community wiki. The fail method in Monad is considered by some to be a wart; a somewhat arbitrary addition to the class that does not come from the original category theory. But of course in the current state of things, many Monad types have logical and useful fail instances. The MonadPlus class is a sub-class of Monad that provides an mzero method which logically encapsulates the idea of failure in a monad. So a library designer who wants to write some monadic code that does some sort of failure handling can choose to make his code use the fail method in Monad or restrict his code to the MonadPlus class, just so that he can feel good about using mzero, even though he doesn't care about the monoidal combining mplus operation at all. Some discussions on this subject are in this wiki page about proposals to reform the MonadPlus class. So I guess I have one specific question: What monad instances, if any, have a natural fail method, but cannot be instances of MonadPlus because they have no logical implementation for mplus? But I'm mostly interested in a discussion about this subject. Thanks! EDIT: One final thought occured to me. I recently learned (even though it's right there in the docs for fail) that monadic "do" notation is desugared in such a way that pattern match failures, as in (x:xs) <- return [] call the monad's fail. It seems like the language designers must have been strongly influenced by the prospect of some automatic failure handling built in to haskell's syntax in their inclusion of fail in Monad.

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  • Why is UseCompatibleTextRendering needed here?

    - by HotOil
    Hi, I think I'm missing something fundamental. Please tell me what it is, if you can. I have developed a little C++ WinForms app using VS2008. So it is built using .NET 3.5 SP1. My development box is Win7, if that matters. The default value of UseCompatibleTextRendering property in WinForms controls is false in this version of VStudio. And this should not matter to me, I don't think. I don't have any custom-drawn text or controls. The app looks good running on my Win7 box. If I package it up (dragging along .NET 3.5) and install it on one of our WinXP desktops, the buttons and labels don't look good; the text is chopped off in them. If I set UseCompatibleTextRendering to true and then run it on the XP boxes, the text fits into the buttons and labels. My question is: Why? The installation puts .Net 3.5 on the XP boxes, so the app should be able to find and use the right version of WinForms, right? I should note that before I put my app + .NET 3.5 on these boxes, they have no .NET at all. They do not get automatic Microsoft updates; our IT guy gates the patches and upgrades. [ This sort of thing has happened before with apps I create.. they look/work great on the Engineering machines, because we maintain those and they mostly have up-to-date stuff. When they are run on the corporate boxes, they usually don't run and need the VCredist installed. ] Back to the question at hand: The text looks better with the UseCompatibleTextRendering set to false, so I'd rather keep it that way, if I can. I'd like to understand what might be missing on those XP boxes that is making the text not fit. Thanks S

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  • Advanced All In One .NET Framework (should i go for a software factory ?)

    - by alfredo dobrekk
    Hi, i m starting a new project that would basically take input from user and save them to database among about 30 screens, and i would like to find a framework that will allow the maximum number of these features out of the box : .net c#. windows form. unit testing continuous integration logging screens with lists, combo boxes, text boxes, add, delete, save, cancel that are easy to update when you add a property to your classes or a field to your database. auto completion on controls to help user find its way use of an orm like nhibernate easy multithreading and display of wait screens for user easy undo redo tabbed child windows search forms ability to grant access to some functionnalities according to user profiles mvp/mvvm or whatever design patterns either some code generation from database to c# classe or generation of database schema from c# classes some kind of database versioning / upgrade to easily update database when i release patches to application once in production automatic control resizing code metrics analysis some code generator i can use against my entities that would generate some rough form i can rearrange after code documentation generator ... At this point i have 3 options : Build from scratch on top of clr :( Find functionnalities among several open source framework and use them as a stack for infrastucture Find a "software factory" I know its lot but i really would like to use existing code to build upon so i can focus on business rules. What open source tools would u use to achieve these ?

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