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  • Forum achievements on a phpBB3 board?

    - by VIVA LA NWO
    I recently started a new community. The forum software is phpBB3, and so far so good. In an attempt to make my community more unique and interesting, I had to idea of having user achievements. Let me give you a quick run-down. Each user has achievements that they can earn (these will probably be across all users), for example an achievement for when a user hits 1,000 posts, when they upload an avatar, when one of their topics gets 1,000 views and so on. Each achievement has points, for example an achievement like uploading an avatar will be 10 points and reaching 10,000 points will grant 50 achievement points. If anyone here plays World of Warcraft you may be seeing where I'm getting the ideas from. :) What I'm struggling to get my head around though is how exactly to code this... I could keep a record of all users activity and add it to a special database table possibly, and then check via cron every minute or so if any user has met achievement criteria... but then I also want it controllable through the ACP so I can easily add new achievements and change their points etc. My mind is pretty blank when it comes to anything but the most simple things. What I really posted here for was feedback on the idea and how you all think I should go about doing this. The coding part should be pretty simple for me once I get my head around how phpBBB MODs need to be written. Thanks for reading, and I look forward to your replies. :)

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  • What are the lengths/limits C preprocessor as a language creation tool? Where can I learn more about

    - by Weston C
    In his FAQ @ http://www2.research.att.com/~bs/bs_faq.html#bootstrapping, Bjarne Stroustrup says: To build [Cfront, the first C++ compiler], I first used C to write a "C with Classes"-to-C preprocessor. "C with Classes" was a C dialect that became the immediate ancestor to C++... I then wrote the first version of Cfront in "C with Classes". When I read this, it piqued my interest in the C preprocessor. I'd seen its macro capabilities as suitable for simplifying common expressions but hadn't thought about its ability to significantly add to syntax and semantics on the level that I imagine bringing classes to C took. So now I have a couple of questions on my mind: 1) Are there other examples of this approach to bootstrapping a language off of C? 2) Is the source to Stroustrup's original work available anywhere? 3) Where could I learn more about the specifics of utilizing this technique? 4) What are the lengths/limits of that approach? Could one, say, create a set of preprocessor macros that let someone write in something significantly Lisp/Scheme like?

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  • Need help implementing this algorithm with map Hadoop MapReduce

    - by Julia
    Hi all! i have algorithm that will go through a large data set read some text files and search for specific terms in those lines. I have it implemented in Java, but I didnt want to post code so that it doesnt look i am searching for someone to implement it for me, but it is true i really need a lot of help!!! This was not planned for my project, but data set turned out to be huge, so teacher told me I have to do it like this. EDIT(i did not clarified i previos version)The data set I have is on a Hadoop cluster, and I should make its MapReduce implementation I was reading about MapReduce and thaught that i first do the standard implementation and then it will be more/less easier to do it with mapreduce. But didnt happen, since algorithm is quite stupid and nothing special, and map reduce...i cant wrap my mind around it. So here is shortly pseudo code of my algorithm LIST termList (there is method that creates this list from lucene index) FOLDER topFolder INPUT topFolder IF it is folder and not empty list files (there are 30 sub folders inside) FOR EACH sub folder GET file "CheckedFile.txt" analyze(CheckedFile) ENDFOR END IF Method ANALYZE(CheckedFile) read CheckedFile WHILE CheckedFile has next line GET line FOR(loops through termList) GET third word from line IF third word = term from list append whole line to string buffer ENDIF ENDFOR END WHILE OUTPUT string buffer to file Also, as you can see, each time when "analyze" is called, new file has to be created, i understood that map reduce is difficult to write to many outputs??? I understand mapreduce intuition, and my example seems perfectly suited for mapreduce, but when it comes to do this, obviously I do not know enough and i am STUCK! Please please help.

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  • array of structures, or structure of arrays?

    - by Jason S
    Hmmm. I have a table which is an array of structures I need to store in Java. The naive don't-worry-about-memory approach says do this: public class Record { final private int field1; final private int field2; final private long field3; /* constructor & accessors here */ } List<Record> records = new ArrayList<Record>(); If I end up using a large number ( 106 ) of records, where individual records are accessed occasionally, one at a time, how would I figure out how the preceding approach (an ArrayList) would compare with an optimized approach for storage costs: public class OptimizedRecordStore { final private int[] field1; final private int[] field2; final private long[] field3; Record getRecord(int i) { return new Record(field1[i],field2[i],field3[i]); } /* constructor and other accessors & methods */ } edit: assume the # of records is something that is changed infrequently or never I'm probably not going to use the OptimizedRecordStore approach, but I want to understand the storage cost issue so I can make that decision with confidence. obviously if I add/change the # of records in the OptimizedRecordStore approach above, I either have to replace the whole object with a new one, or remove the "final" keyword. kd304 brings up a good point that was in the back of my mind. In other situations similar to this, I need column access on the records, e.g. if field1 and field2 are "time" and "position", and it's important for me to get those values as an array for use with MATLAB, so I can graph/analyze them efficiently.

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  • Eclipse PDT "tips" ?

    - by Pascal MARTIN
    Hi ! (Yes, this is a quite opened and general and subjective question -- it's by design, cause I want tips you think are great !) I'm using Eclipse PDT 2.1 to work in PHP, either for small and/or big projects -- I've been doing so for quite some times, now, actually (since before 1.0 stable, if I remember well)... I was wondering if any of you did know "tips" to be more efficient. Let met explain more in details : I know about things like plugins like Aptana (better editor for JS/CSS), Subversive (for SVN access), RSE, Filesync, integrating Xdebug's debugger, ... What I mean by "tips" is more some little things you discovered one day and since use all the time -- and allow you to be more efficient in your PHP projects. Some examples of "tips" that come to my mind, and that already know and use : ctrl+space to open the list of suggestions for functions / variables names ctrl+shift+R (navigate > open resource) to open a popup which show only files which names contain what you type ; ie, quick opening of files this one might be the perfect example : I know this one is not often known by coworkers and they find it as useful as I do ; so, I guess there might be lots of other things like this one I don't know myself ^^ ctrl+M to switch to full-screen view for the editor (instead of double-click on tabs bar) shift+F2 while on a function name, to open it's page if the PHP manual in a browser Attention Mac Users use Command instead Control. I guess you get the point ; but I'm really open to any suggestion (be it eclipse-related in general, of more PHP/PDT-specific) that can help be be more efficient :-) Anyway, thanks in advance for your help !

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  • Java Executor: Small tasks or big ones?

    - by Arash Shahkar
    Consider one big task which could be broken into hundreds of small, independently-runnable tasks. To be more specific, each small task is to send a light network request and decide upon the answer received from the server. These small tasks are not expected to take longer than a second, and involve a few servers in total. I have in mind two approaches to implement this using the Executor framework, and I want to know which one's better and why. Create a few, say 5 to 10 tasks each involving doing a bunch of send and receives. Create a single task (Callable or Runnable) for each send & receive and schedule all of them (hundreds) to be run by the executor. I'm sorry if my question shows that I'm lazy to test these and see for myself what's better (at least performance-wise). My question, while looking after an answer to this specific case, has a more general aspect. In situations like these when you want to use an executor to do all the scheduling and other stuff, is it better to create lots of small tasks or to group those into a less number of bigger tasks?

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  • Learning libraries without books or tutorials

    - by Kawili-wili
    While many ask questions about where to find good books or tutorials, I'd like to take the opposite tack. I consider myself to be an entry-level programmer ready to move up to mid-level. I have written code in c, c++, c#, perl, python, clojure, vb, and java, so I'm not completely clueless. Where I see a problem in moving to the next level is learning to make better use of the literally hundreds upon hundreds of libraries available out there. I seem paralyzed unless there is a specific example in a book or tutorial to hand-hold me, yet I often read in various forums where another programmer attempts to assist with a question. He/she will look through the docs or scan the available classes/methods in their favorite IDE and seem to grok what's going on in a relatively short period of time, even if they had no previous experience with that specific library or function. I yearn to break the umbilical chord of constantly spending hour upon hour searching and reading, searching and reading, searching and reading. Many times there is no book or tutorial, or if there is, the discussion glosses over my specific needs or the examples shown are too far off the path for the usage I had in mind or the information is outdated and makes use of deprecated components or the library itself has fallen out of mainstream, yet is still perfectly usable (but no docs, books, or tutorials to hand-hold). My question is: In the absence of books or tutorials, what is the best way to grok new or unfamiliar libraries? I yearn to slicken the grok path so I can get down to the business of doing what I love most -- coding.

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  • how to create a mootools 1.1 function with array

    - by liz
    i have a series of select lists, that i am using to populate text boxes with ids. so you click a select option and another text box is filled with its id. with just one select/id pair this works fine, but i have multiples, and the only thing that changes is the id of the select and input.. in fact just the ending changes, the inputs all start with featredproductid and the select ids all start with recipesproduct and then both end with the category. i know that listing this over and over for each category is not the way to do it. i think i need to make an array of the categories var cats = ['olive oil', "grains", "pasta"] and then use a forEach function? maybe? here is the clunky code window.addEvent('domready', function() { $('recipesproductoliveoil').addEvent('change', function(e){ pidselected = this.options[this.selectedIndex].getProperty('value') ; $("featuredproductidoliveoil").setProperties({ value: pidselected}); ; }); $('recipesproductgrains').addEvent('change', function(e){ pidselected = this.options[this.selectedIndex].getProperty('value') ; $("featuredproductidgrains").setProperties({ value: pidselected}); ; }); $('recipesproductpasta').addEvent('change', function(e){ pidselected = this.options[this.selectedIndex].getProperty('value') ; $("featuredproductidpasta").setProperties({ value: pidselected}); ; }); $('recipesproductpantry').addEvent('change', function(e){ pidselected = this.options[this.selectedIndex].getProperty('value') ; $("featuredproductidpantry").setProperties({ value: pidselected}); ; }); }); keep in mind this is mootools 1.1 (no i cant update it sorry). i am sure this is kind of basic, something i seem to have wrapping my brain around. but i am quite sure doing it as above is not really good...

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  • select all values from a dimension for which there are facts in all other dimensions

    - by ideasculptor
    I've tried to simplify for the purposes of asking this question. Hopefully, this will be comprehensible. Basically, I have a fact table with a time dimension, another dimension, and a hierarchical dimension. For the purposes of the question, let's assume the hierarchical dimension is zip code and state. The other dimension is just descriptive. Let's call it 'customer' Let's assume there are 50 customers. I need to find the set of states for which there is at least one zip code in which EVERY customer has at least one fact row for each day in the time dimension. If a zip code has only 49 customers, I don't care about it. If even one of the 50 customers doesn't have a value for even 1 day in a zip code, I don't care about it. Finally, I also need to know which zip codes qualified the state for selection. Note, there is no requirement that every zip code have a full data set - only that at least one zip code does. I don't mind making multiple queries and doing some processing on the client side. This is a dataset that only needs to be generated once per day and can be cached. I don't even see a particularly clean way to do it with multiple queries short of simply brute-force iteration, and there are a heck of a lot of 'zip codes' in the data set (not actually zip codes, but the there are approximately 100,000 entries in the lower level of the hierarchy and several hundred in the top level, so zipcode-state is a reasonable analogy)

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  • How do I initialize the controls in an InsertItemTemplate?

    - by Slauma
    I have - for instance - an asp:FormView which supports Read, Insert, Update, Delete and is bound to a DataSource: <asp:FormView ID="FormView1" runat="server" DataSourceID="ObjectDataSource1" > <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("MyText") %>' /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("MyText") %>' /> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("MyText") %>' /> </InsertItemTemplate> </asp:FormView> If I am in Read-Mode or Edit-Mode the control is initialized with the property MyText of the current object which is bound to the FormView. But when I go to Insert-Mode I do not have a "current object" (FormView1.DataItem is indeed null) and the controls are empty. If I want to have my TextBox control initialized with a specific value how can I do that? In which event can I hook in to set default values to the controls in the InsertItemTemplate? Especially I have in mind using an ObjectDataSource. I was expecting that the InsertItemTemplate is initialized with a business object which underlies my ObjectDataSource and which is created by the ASP.NET framework simply by using its default constructor when the InsertItemTemplate gets activated. In the default constructor I would init the class members to the default values I'd like to have in my controls of the InsertItemTemplate. But unfortunately that's not the case: No "default" object is created and bound to the FormView. So it seems I have to initialize all controls separately or to create the default object manually and bind it to the InsertItemTemplate of the FormView. But how and where can I do that? Thanks in advance!

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  • How to keep confirmation messages after POST while doing a post-submit redirect?

    - by MicE
    Hello, I'm looking for advise on how to share certain bits of data (i.e. post-submit confirmation messages) between individual requests in a web application. Let me explain: Current approach: user submits an add/edit form for a resource if there were no errors, user is shown a confirmation with links to: submit a new resource (for "add" form) view the submitted/edited resource view all resources (one step above in hierarchy) user then has to click on one of the three links to proceed (i.e. to the page "above") Progmatically, the form and its confirmation page are one set of classes. The page above that is another. They can technically share code, but at the moment they are both independent during processing of individual requests. We would like to amend the above as follows: user submits an add/edit form for a resource if there were no errors, the user is redirected to the page with all resources (one step above in hierarchy) with one or more confirmation messages displayed at the top of the page (i.e. success message, to whom was the request assigned, etc) This will: save users one click (they have to go through a lot of these add/edit forms) the post-submit redirect will address common problems with browser refresh / back-buttons What approach would you recommend for sharing data needed for the confirmation messages between the two requests, please? I'm not sure if it helps, it's a PHP application backed by a RESTful API, but I think that this is a language-agnostic question. A few simple solutions that come to mind are to share the data via cookies or in the session, this however breaks statelessness and would pose a significant problem for users who work in several tabs (the data could clash together). Passing the data as GET parameters is not suitable as we are talking about several messages which are dynamic (e.g. changing actors, dates). Thanks, M.

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  • Best practices for withstanding launch day traffic burst

    - by Sam McAfee
    We are working on a website for a client that (for once) is expected to get a fair amount of traffic on day one. There are press releases, people are blogging about it, etc. I am a little concerned that we're going to fall flat on our face on day one. What are the main things you would look at to ensure (in advance without real traffic data) that you can stay standing after a big launch. Details: This is a L/A/M/PHP stack, using an internally developed MVC framework. This is currently being launched on one server, with Apache and MySQL both on it, but we can break that up if need be. We are already installing memcached and doing as much PHP-level caching as we can think of. Some of the pages are rather query intensive, and we are using Smarty as our template engine. Keep in mind there is no time to change any of these major aspects--this is the just the setup. What sorts of things should we watch out for?

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  • Create a real time web application using .net framework and azure - very confused

    - by test
    Let us say I would like a simple (yet complex) web application where there is continuous READING AND WRITING to the sql azure database. Let us say I am tracking a location, and I would like it to be updated very frequently (lets take the worst case: 1 second). From the little knowledge I have, I think that this involves the use of the database to continuously write the location to the database, and continuously read from the database to update another person through a website. Do you please have any suggestion which technologies can I use? Is there a simple way? I heard about node.js, signalR. I have no idea how to use them, if they are really what I need. the last tutorial I checked out simply uses a while(true) loop..but I don't think that that's something good to keep a thread continuously busy... Do I have to create some background task? Do I have to create some web service? This is a school project and I wish not to go for the most difficult option, but if there is some sort of solution, challenge accepted :) Can you please help me? Since I have asked many questions here and yet I have no solution in mind

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  • API-based solutions for sending payments to people without bank accounts

    - by Tauren
    I'm looking for inexpensive ways to send payments to hundreds or thousands of individual contractors, even if they do not have a bank account. Currently I only need to support payment in the USA, but may eventually be international. Here's the scenario: I offer a service that allows an organization or manager-type person to coordinate contractors for very short term jobs. These jobs are typically only an hour or two in length. A contractor may get only one job over an entire month, several jobs spread out over a month, multiple jobs on a single day, or any other combination. Thus, a single contractor could earn as little as one job's payment up to potentially payment for dozens. Payment for a month could be as little as $10 up to $1000's. Right now, the system provides payroll reports to the manager and it is the manager's responsibility to produce checks, stuff envelopes, and send mail via the US postal service. I'd like to remove this burden from the manager and have all the payments taken care of for them automatically by the system. I'm not sure where to start or what the best options would be. I'm starting to look into the following solutions, but don't know specifics yet and would like some advice before pursuing them. I'd also like to hear about other ideas or suggestions. PayPal (Send Money, Adaptive Payments, x.com, other???) Amazon (Flexible Payments System?) Fund some sort of pre-paid debit card? Web service with API that mails checks for you? Direct deposit via a bank API (for users with bank accounts)? The problem is that many of these contractors may not be able to obtain bank accounts or credit cards within the USA. I don't mind doing a hybrid of solutions, but are there any that would work well with this issue? I want the solution to be easy to use for the contractors, meaning that they can get the money easily (via check in the mail, debit card ATM withdrawal, etc.)

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  • Storing header and data sections in a CSV file

    - by morpheous
    This should be relatively easy to do, but after several hours straight programming my mind seems a bit frazzled and could do with some help. I have a C++ class which I am currently using to store read/write data to file. I was initially using binary data, but have decided to store the data as CSV in order to let programs written in other languages be able to load the data. The C++ class looks a bit like this: class BinaryData { public: BinaryData(); void serialize(std::ostream& output) const; void deserialize(std::istream& input); private: Header m_hdr; std::vector<Row> m_rows; }; I am simply rewriting the serialize/deserialize methods to write to a CSV file. I am not sure on the "best" way to store a header section and a "data" section in a "flat" CSV file though - any suggestions on the most sensible way to do this?

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  • Which technology should I use to transform my latex documents into html documents

    - by Matthias Günther
    Hey, I want to write a little program that transforms my TeX files into HTML. I want to parse the documents and turn the macros (the build-in and of course my own) into HTML pieces. Here are my requirements: predefined rules (e.g. begin{itemize} \item text \end{itemize} = <br> <p>text </p> <br/>) defining own CSS style ability to convert formulars (extract the formulars, load them in an imagecreator and then save the jpg/png) easy to maintain and concise I know there are several technologies out there, but I don't exactly know which is the best for me. Here are the technologies which flow into my mind Ruby (I/O is easy, formular loading via webrat), XML XSLT (I don't think that I need just overhead) perl (there are many libs out there but I'm not quite familiar with it) bash (I worked with sed and was surprised how easy it was to work with regular expressions) latex2html ... (these converters won't work for me and they don't give me freedom in parsing) Any suggestions, hints and comments are welcome. Thanks for your time, folks.

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  • Access 2007 not allowing user to delete record in subform

    - by Todd McDermid
    Good day... The root of my issue is that there's no context menu allowing the user to delete a row from a form. The "delete" button on the ribbon is also disabled. In Access 2003, apparently this function was available, but since our recent "upgrade" to 2007 (file is still in MDB format) it's no longer there. Please keep in mind I'm not an Access dev, nor did I create this app - I inherited support for it. ;) Now for the details, and what I've tried. The form in question is a subform on a larger form. I've tried turning "AllowDeletes" on on both forms. I've checked the toolbar and ribbon properties on the forms to see if they loaded some custom stuff, but no. I've tried changing the "record locks" to "on edit", no joy. I examined the query to see if it was "too complicated" to permit a delete - as far as I can tell, it's a very simple two (linked) table join. Compared to another form in this app that does permit row deletes, it has a much more complicated (multi-join, built on queries) query. Is there a resource that would describe the required conditions for allowing deletes? Thanks in advance...

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  • Five unique, random numbers from a subset

    - by tau
    I know similar questions come up a lot and there's probably no definitive answer, but I want to generate five unique random numbers from a subset of numbers that is potentially infinite (maybe 0-20, or 0-1,000,000). The only catch is that I don't want to have to run while loops or fill an array. My current method is to simply generate five random numbers from a subset minus the last five numbers. If any of the numbers match each other, then they go to their respective place at the end of the subset. So if the fourth number matches any other number, it will bet set to the 4th from the last number. Does anyone have a method that is "random enough" and doesn't involve costly loops or arrays? Please keep in mind this a curiosity, not some mission-critical problem. I would appreciate it if everyone didn't post "why are you having this problem?" answers. I am just looking for ideas. Thanks a lot!

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  • Why does using the Asynchronous Programming Model in .Net not lead to StackOverflow exceptions?

    - by uriDium
    For example, we call BeginReceive and have the callback method that BeginReceive executes when it has completed. If that callback method once again calls BeginReceive in my mind it would be very similar to recursion. How is that this does not cause a stackoverflow exception. Example code from MSDN: private static void Receive(Socket client) { try { // Create the state object. StateObject state = new StateObject(); state.workSocket = client; // Begin receiving the data from the remote device. client.BeginReceive( state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ReceiveCallback), state); } catch (Exception e) { Console.WriteLine(e.ToString()); } } private static void ReceiveCallback( IAsyncResult ar ) { try { // Retrieve the state object and the client socket // from the asynchronous state object. StateObject state = (StateObject) ar.AsyncState; Socket client = state.workSocket; // Read data from the remote device. int bytesRead = client.EndReceive(ar); if (bytesRead > 0) { // There might be more data, so store the data received so far. state.sb.Append(Encoding.ASCII.GetString(state.buffer,0,bytesRead)); // Get the rest of the data. client.BeginReceive(state.buffer,0,StateObject.BufferSize,0, new AsyncCallback(ReceiveCallback), state); } else { // All the data has arrived; put it in response. if (state.sb.Length > 1) { response = state.sb.ToString(); } // Signal that all bytes have been received. receiveDone.Set(); } } catch (Exception e) { Console.WriteLine(e.ToString()); } }

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  • In a combobox, how do I determine the highlighted item (not selected item)?

    - by Harold Bamford
    First, fair warning: I am a complete newbie with C# and WPF. I have a combobox (editable, searchable) and I would like to be able to intercept the Delete key and remove the currently highlighted item from the list. The behavior I'm looking for is like that of MS Outlook when entering in email addresses. When you give a few characters, a dropdown list of potential matches is displayed. If you move to one of these (with the arrow keys) and hit Delete, that entry is permanently removed. I want to do that with an entry in the combobox. Here is the XAML (simplified): <ComboBox x:Name="Directory" KeyUp="Directory_KeyUp" IsTextSearchEnabled="True" IsEditable="True" Text="{Binding Path=CurrentDirectory, Mode=TwoWay}" ItemsSource="{Binding Source={x:Static self:Properties.Settings.Default}, Path=DirectoryList, Mode=TwoWay}" / The handler is: private void Directory_KeyUp(object sender, KeyEventArgs e) { ComboBox box = sender as ComboBox; if (box.IsDropDownOpen && (e.Key == Key.Delete)) { TrimCombobox("DirectoryList", box.HighlightedItem); // won't compile! } } When using the debugger, I can see box.HighlightedItem has the value I want but when I try and put in that code, it fails to compile with: System.Windows.Controls.ComboBox' does not contain a definition for 'HighlightedItem'... So: how do I access that value? Keep in mind that the item has not been selected. It is merely highlighted as the mouse hovers over it. Thanks for your help.

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  • Document management, SCM ?

    - by tsunade
    Hello, This might not be a hard core programming question, but it's related to some of the tools used by programmers I suspect. So we're a bunch of people each with a bunch of documents and a bunch of different computers on a bunch of operating systems (well, only 2, linux and windows). The best way these documents can be stored/managed is if they were available offline (the laptop might not always be online) but also synchronized between all the machines. Having a server with extra reliable storage be a "base repository" seems like a good idea to me. Using a SCM comes to my mind and I've tried Subversion, and it seems to be a good thing that it uses a centralized repository - but: When checking out the total size of the checkout is roughly double the original size. Big files or big repositories seem to slow it down. Also I've tried rsync, which might work - but it's a bit rough when it comes to the potential conflict. Finally I've tried Unison (which is a wrapping of rsync, I think) and while it works it becomes horribly slow for the big directories we have here since it has to scan everything. So the question is - is there a SCM tool out there that is actually practial to use for a big bunch of both small and big files? If thats a NO - does anyone know other tools that do this job? Thanks for reading :)

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  • How to handle 'this' pointer in constructor?

    - by Kyle
    I have objects which create other child objects within their constructors, passing 'this' so the child can save a pointer back to its parent. I use boost::shared_ptr extensively in my programming as a safer alternative to std::auto_ptr or raw pointers. So the child would have code such as shared_ptr<Parent>, and boost provides the shared_from_this() method which the parent can give to the child. My problem is that shared_from_this() cannot be used in a constructor, which isn't really a crime because 'this' should not be used in a constructor anyways unless you know what you're doing and don't mind the limitations. Google's C++ Style Guide states that constructors should merely set member variables to their initial values. Any complex initialization should go in an explicit Init() method. This solves the 'this-in-constructor' problem as well as a few others as well. What bothers me is that people using your code now must remember to call Init() every time they construct one of your objects. The only way I can think of to enforce this is by having an assertion that Init() has already been called at the top of every member function, but this is tedious to write and cumbersome to execute. Are there any idioms out there that solve this problem at any step along the way?

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  • accessing private variable from member function in PHP

    - by Carson Myers
    I have derived a class from Exception, basically like so: class MyException extends Exception { private $_type; public function type() { return $this->_type; //line 74 } public function __toString() { include "sometemplate.php"; return ""; } } Then, I derived from MyException like so: class SpecialException extends MyException { private $_type = "superspecial"; } If I throw new SpecialException("bla") from a function, catch it, and go echo $e, then the __toString function should load a template, display that, and then not actually return anything to echo. This is basically what's in the template file <div class="<?php echo $this->type(); ?>class"> <p> <?php echo $this->message; ?> </p> </div> in my mind, this should definitely work. However, I get the following error when an exception is thrown and I try to display it: Fatal error: Cannot access private property SpecialException::$_type in C:\path\to\exceptions.php on line 74 Can anyone explain why I am breaking the rules here? Am I doing something horribly witty with this code? Is there a much more idiomatic way to handle this situation? The point of the $_type variable is (as shown) that I want a different div class to be used depending on the type of exception caught.

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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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  • What are some of the core principles needed to master Multi threading using Delphi?

    - by Gary Becks
    I am kind of new to programming in general (about 8 months with on and off in delphi and a little python here and there) and I am in the process of buying some books. I am interested in learning about concurrent programming and building multi threaded apps using Delphi. Whenever I do a search for "multithreading delphi" or "delphi multithreading tutorial" I seem to get conflicting results as some of the stuff is about using certain libraries (omnithread library) and other stuff seems to be more geared towards programmers with more experience. I have studied quite a few books on delphi and for the most part they seem to kind of skim the surface and not really go into depth on the subject. I have a friend who is a programmer (he uses c++) who recommends I learn what is actually going on with the underlying system when using threads as opposed to jumping into how to actually implement them in my programs first. On amazon.com there are quite a few books on concurrent programming but none of them seem to be made with Delphi in mind. Basically I need to know what are the main things I should be focused on learning before jumping into using threads, if I can/should attempt to learn them using books that are not specifically aimed at delphi developers (don't want to confuse myself reading books with a bunch of code examples in other languages right now) and if there are any reliable resources/books on the subject that anyone here could recommend. Thanks in advance.

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