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  • How to factorize code in Unreal Kismet (i.e. "Material Function"s for Kismet)

    - by Georges Dupéron
    In the Unreal Development Kit, when using the Material Editor, one can factorize frequently-used groups of nodes by creating a Material Function (content Browser ? right-click ? new matrial function, IIRC). When defining the behaviour of some actor in Kismet, one can easily have a dozen nodes involved. If I have many actors that share the same behaviour, then I'll copy-paste these nodes, and change the variables so they point to the other actors. This leads to inconsistencies (a modification in the behaviour of an actor isn't propagated in the copy-pasted nodes), complexity (you end up with hundreds of nodes), and generally useless effort. My question is : Can I create a "kismet function", just like a material function ? Note: I'd rather avoid using UnrealScript. I don't even know where to type UnrealScripts, don't know where the documentation is and more generally don't have enough time to invest in learning UnrealScript. This "kismet function" feature must be usable by graphists (with little programming knowledge). If a (simple) script suffices to add this feature in the Kismet editor, so that one can create several "functions" without using UnrealScript, then fine, but I don't really want to have to write a script each time I want to factorize a few nodes. Thanks for any information !

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  • Is there a (family of) monotonically non-decreasing noise function(s)?

    - by Joe Wreschnig
    I'd like a function to animate an object moving from point A to point B over time, such that it reaches B at some fixed time, but its position at any time is randomly perturbed in a continuous fashion, but never goes backwards. The objects move along straight lines, so I only need one dimension. Mathematically, that means I'm looking for some continuous f(x), x ? [0,1], such that: f(0) = 0 f(1) = 1 x < y ? f(x) = f(y) At "most" points f(x + d) - f(x) bears no obvious relation to d. (The function is not uniformly increasing or otherwise predictable; I think that's also equivalent to saying no degree of derivative is a constant.) Ideally, I would actually like some way to have a family of these functions, providing some seed state. I'd need at least 4 bits of seed (16 possible functions), for my current use, but since that's not much feel free to provide even more. To avoid various issues with accumulation errors, I'd prefer the function not require any kind of internal state. That is, I want it to be a real function, not a programming "function".

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  • Removing/Adding a specific variable from an object inside javascript array? [migrated]

    - by hustlerinc
    I have a map array with objects stuffed with variables looking like this: var map = [ [{ground:0, object:1}, {ground:0, item:2}, {ground:0, object:1, item:2}], [{ground:0, object:1}, {ground:0, item:2}, {ground:0, object:1, item:2}] ]; Now I would like to be able to delete and add one of the variables like item:2. 1) What would I use to delete specific variables? 2) What would I use to add specific variables? I just need 2 short lines of code, the rest like detecting if and where to execute I've figured out. I've tried delete map[i][j].item; with no results. Help appreciated.

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  • Is it justified to use project-wide unique function and variable names to help future refactoring?

    - by kahoon
    Refactoring tools (like ReSharper) often can't be sure whether to rename a given identifier when, for example refactoring a JavaScript function. I guess this is a consequence of JavaScript's dynamic nature. ReSharper solves this problem by offering to rename reasonable lexical matches too. The developer can opt out of renaming certain functions, if he finds that the lexical match is purely accidental. This means that the developer has to approve every instance that will be affected by the renaming. For example let's consider we have two Backbone classes which are used completely independently from each other in our application: var Header = Backbone.View.extend({ close: function() {...} }) var Dialog = Backbone.View.extend({ close: function() {...} }) If you try to rename Dialog's close method to for example closeAndNotify, then ReSharper will offer to rename all occurences of Header's close method just because they are the same lexically prior to the renaming. To avoid this problem, please consider this: var Header = Backbone.View.extend({ closeHeader: function() {...} }) var Dialog = Backbone.View.extend({ closeDialog: function() {...} }) Now you can rename closeDialog unambiguously - given that you have no other classes having a method with the same name. Is it worth it to name my functions this way to help future refactoring?

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  • "'0.offsetWidth' is null or not an object" - Coda Slider - Javascript Error Question

    - by bgadoci
    I implemented the Coda Slider tutorial successfully that is located here: http://jqueryfordesigners.com/coda-slider-effect/ The slider works great but I am getting a javascript error that I am not sure how to fix. The error says: '0.offsetWidth' is null or not an object coda-slider.js, line 19 character 3 Not sure how to fix it. Anyone have any ideas? Here is my js and css (don't think I need to upload the HTML but let me know if that helps). JS (coda-slider.js) // when the DOM is ready... $(document).ready(function () { var $panels = $('#slider .scrollContainer > div'); var $container = $('#slider .scrollContainer'); // if false, we'll float all the panels left and fix the width // of the container var horizontal = true; // float the panels left if we're going horizontal if (horizontal) { $panels.css({ 'float' : 'left', 'position' : 'relative' // IE fix to ensure overflow is hidden }); // calculate a new width for the container (so it holds all panels) $container.css('width', $panels[0].offsetWidth * $panels.length); <------line 19 } // collect the scroll object, at the same time apply the hidden overflow // to remove the default scrollbars that will appear var $scroll = $('#slider .scroll').css('overflow', 'hidden'); // apply our left + right buttons $scroll .before('<img class="scrollButtons left" src="/images/layout/navigation/scroll_left.png" />') .after('<img class="scrollButtons right" src="/images/layout/navigation/scroll_right.png" />'); // handle nav selection function selectNav() { $(this) .parents('ul:first') .find('a') .removeClass('selected') .end() .end() .addClass('selected'); } $('#slider .navigation').find('a').click(selectNav); // go find the navigation link that has this target and select the nav function trigger(data) { var el = $('#slider .navigation').find('a[href$="' + data.id + '"]').get(0); selectNav.call(el); } if (window.location.hash) { trigger({ id : window.location.hash.substr(1) }); } else { $('ul.navigation a:first').click(); } // offset is used to move to *exactly* the right place, since I'm using // padding on my example, I need to subtract the amount of padding to // the offset. Try removing this to get a good idea of the effect var offset = parseInt((horizontal ? $container.css('paddingTop') : $container.css('paddingLeft')) || 0) * -1; var scrollOptions = { target: $scroll, // the element that has the overflow // can be a selector which will be relative to the target items: $panels, navigation: '.navigation a', // selectors are NOT relative to document, i.e. make sure they're unique prev: 'img.left', next: 'img.right', // allow the scroll effect to run both directions axis: 'xy', onAfter: trigger, // our final callback offset: offset, // duration of the sliding effect duration: 500, // easing - can be used with the easing plugin: // http://gsgd.co.uk/sandbox/jquery/easing/ easing: 'swing' }; // apply serialScroll to the slider - we chose this plugin because it // supports// the indexed next and previous scroll along with hooking // in to our navigation. $('#slider').serialScroll(scrollOptions); // now apply localScroll to hook any other arbitrary links to trigger // the effect $.localScroll(scrollOptions); // finally, if the URL has a hash, move the slider in to position, // setting the duration to 1 because I don't want it to scroll in the // very first page load. We don't always need this, but it ensures // the positioning is absolutely spot on when the pages loads. scrollOptions.duration = 1; $.localScroll.hash(scrollOptions); }); CSS #slider { margin-left: 35px; position: relative; width: 875px; } .scroll { position: relative; width: 875px; height: 268px; overflow: auto; /* fix for IE to respect overflow */ background: #FFFFFF scroll 0; } .scrollContainer div.panel { position: relative; height: 210px; width: 875px; /* change to 560px if not using JS to remove rh.scroll */ } .scrollButtons { position: absolute; top: 115px; cursor: pointer; } .scrollButtons.left { left: -20px; } .scrollButtons.right { right: -20px; }

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  • "Access is denied" JavaScript error when trying to access the document object of a programmatically-

    - by Bungle
    I have project in which I need to create an <iframe> element using JavaScript and append it to the DOM. After that, I need to insert some content into the <iframe>. It's a widget that will be embedded in third-party websites. I don't set the "src" attribute of the <iframe> since I don't want to load a page; rather, it is used to isolate/sandbox the content that I insert into it so that I don't run into CSS or JavaScript conflicts with the parent page. I'm using JSONP to load some HTML content from a server and insert it in this <iframe>. I have this working fine, with one serious exception - if the document.domain property is set in the parent page (which it may be in certain environments in which this widget is deployed), Internet Explorer (probably all versions, but I've confirmed in 6, 7, and 8) gives me an "Access is denied" error when I try to access the document object of this <iframe> I've created. It doesn't happen in any other browsers I've tested in (all major modern ones). This makes some sense, since I'm aware that Internet Explorer requires you to set the document.domain of all windows/frames that will communicate with each other to the same value. However, I'm not aware of any way to set this value on a document that I can't access. Is anyone aware of a way to do this - somehow set the document.domain property of this dynamically created <iframe>? Or am I not looking at it from the right angle - is there another way to achieve what I'm going for without running into this problem? I do need to use an <iframe> in any case, as the isolated/sandboxed window is crucial to the functionality of this widget. Here's my test code: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <title>Document.domain Test</title> <script type="text/javascript"> document.domain = 'onespot.com'; // set the page's document.domain </script> </head> <body> <p>This is a paragraph above the &lt;iframe&gt;.</p> <div id="placeholder"></div> <p>This is a paragraph below the &lt;iframe&gt;.</p> <script type="text/javascript"> var iframe = document.createElement('iframe'), doc; // create <iframe> element document.getElementById('placeholder').appendChild(iframe); // append <iframe> element to the placeholder element setTimeout(function() { // set a timeout to give browsers a chance to recognize the <iframe> doc = iframe.contentWindow || iframe.contentDocument; // get a handle on the <iframe> document alert(doc); if (doc.document) { // HEREIN LIES THE PROBLEM doc = doc.document; } doc.body.innerHTML = '<h1>Hello!</h1>'; // add an element }, 10); </script> </body> </html> I've hosted it at: http://troy.onespot.com/static/access_denied.html As you'll see if you load this page in IE, at the point that I call alert(), I do have a handle on the window object of the <iframe>; I just can't get any deeper, into its document object. Thanks very much for any help or suggestions! I'll be indebted to whomever can help me find a solution to this.

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  • JPA thinks I'm deleting a detached object

    - by Steve
    So, I've got a DAO that I used to load and save my domain objects using JPA. I finally managed to get the transaction stuff working (with a bunch of help from the folks here...), now I've got another issue. In my test case, I call my DAO to load a domain object with a given id, check that it got loaded and then call the same DAO to delete the object I just loaded. When I do that I get the following: java.lang.IllegalArgumentException: Removing a detached instance mil.navy.ndms.conops.common.model.impl.jpa.Group#10 at org.hibernate.ejb.event.EJB3DeleteEventListener.performDetachedEntityDeletionCheck(EJB3DeleteEventListener.java:45) at org.hibernate.event.def.DefaultDeleteEventListener.onDelete(DefaultDeleteEventListener.java:108) at org.hibernate.event.def.DefaultDeleteEventListener.onDelete(DefaultDeleteEventListener.java:74) at org.hibernate.impl.SessionImpl.fireDelete(SessionImpl.java:794) at org.hibernate.impl.SessionImpl.delete(SessionImpl.java:772) at org.hibernate.ejb.AbstractEntityManagerImpl.remove(AbstractEntityManagerImpl.java:253) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:600) at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:180) at $Proxy27.remove(Unknown Source) at mil.navy.ndms.conops.common.dao.impl.jpa.GroupDao.delete(GroupDao.java:499) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:600) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:304) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204) at $Proxy28.delete(Unknown Source) at mil.navy.ndms.conops.common.dao.impl.jpa.GroupDaoTest.testGroupDaoSave(GroupDaoTest.java:89) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:600) at junit.framework.TestCase.runTest(TestCase.java:164) at junit.framework.TestCase.runBare(TestCase.java:130) at junit.framework.TestResult$1.protect(TestResult.java:106) at junit.framework.TestResult.runProtected(TestResult.java:124) at junit.framework.TestResult.run(TestResult.java:109) at junit.framework.TestCase.run(TestCase.java:120) at junit.framework.TestSuite.runTest(TestSuite.java:230) at junit.framework.TestSuite.run(TestSuite.java:225) at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:130) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196) Now given that I'm using the same DAO instance, and I've not changed EntityManagers (unless Spring does so without letting me know), how can this be a detached object? My DAO code looks like this: public class GenericJPADao implements IWebDao, IDao, IDaoUtil { private static Logger logger = Logger.getLogger (GenericJPADao.class); protected Class voClass; @PersistenceContext(unitName = "CONOPS_PU") protected EntityManagerFactory emf; @PersistenceContext(unitName = "CONOPS_PU") protected EntityManager em; public GenericJPADao() { super ( ); ParameterizedType genericSuperclass = (ParameterizedType) getClass ( ).getGenericSuperclass ( ); this.voClass = (Class) genericSuperclass.getActualTypeArguments ( )[1]; } ... public void delete (INTFC modelObj, EntityManager em) { em.remove (modelObj); } @SuppressWarnings("unchecked") public INTFC findById (Long id) { return ((INTFC) em.find (voClass, id)); } } The test case code looks like: IGroup loadedGroup = dao.findById (group.getId ( )); assertNotNull (loadedGroup); assertEquals (group.getId ( ), loadedGroup.getId ( )); dao.delete (loadedGroup); // - This generates the above exception loadedGroup = dao.findById (group.getId ( )); assertNull(loadedGroup); Can anyone tell me what I'm doing wrong here? Thanks

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  • Jquery change function don’t work properly

    - by user1493448
    I have same id, name two html select. If I change first html select then it’s work properly but If I change second html select then it’s not work. Please can someone point out what I may be doing wrong here? Many thanks. Here is my code: <html> <head> <title>the title</title> <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script> <script type="text/javascript" language="javascript"> $(document).ready(function() { $("#name").change(function(){ $.post( "data.php", $("#testform").serialize(), function(data) { $('#stage1').html(data); } ); var str = $("#testform").serialize(); $("#stage2").text(str); }); }); </script> </head> <body> <div id="stage1" style="background-color:blue; color: white"> STAGE - 1 </div> <form id="testform"> <table> <tr> <td><p>Fruit:</p></td> <td> <select id="name" name="name[]"> <option>Apple</option> <option>Mango</option> <option>Orange</option> <option>Banana</option> </select> </td> </tr> <tr> <td><p>Fruit:</p></td> <td> <select id="name" name="name[]"> <option>Apple</option> <option>Mango</option> <option>Orange</option> <option>Banana</option> </select> </td> </tr> </table> </form> </body> </html> Php code: <?php $fruit=$_REQUEST["name"]; $n = count($fruit); for($i=0;$i<$n; $i++) { echo $fruit[$i]."<br/>"; } ?>

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  • "Invalid Handle Object" when plotting 2 figures Matlab

    - by pinnacler
    I'm having a difficult time understanding the paradigm of Matlab classes vs compared to c++. I wrote code the other day, and I thought it should work. It did not... until I added <handle after the classdef. So I have two classes, landmarks and robot, both are called from within the simulation class. This is the main loop of obj.simulation.animate() and it works, until I try to plot two things at once. DATA.path is a record of all the places a robot has been on the map, and it's updated every time the position is updated. When I try to plot it, by uncommenting the two marked lines below, I get this error: ??? Error using == set Invalid handle object. Error in == simulationsimulation.animate at 45 set(l.lm,'XData',obj.landmarks.apparentPositions(:,1),'YData',obj.landmarks.apparentPositions(:,2)); %INITIALIZE GLOBALS global DATA XX XX = [obj.robot.x ; obj.robot.y]; DATA.i=1; DATA.path = XX; %Setup Plots fig=figure; xlabel('meters'), ylabel('meters') set(fig, 'name', 'Phil''s AWESOME 80''s Robot Simulator') xymax = obj.landmarks.mapSize*3; xymin = -(obj.landmarks.mapSize*3); l.lm=scatter([0],[0],'b+'); %"UNCOMMENT ME"l.pth= plot(0,0,'k.','markersize',2,'erasemode','background'); % vehicle path axis([xymin xymax xymin xymax]); %Simulation Loop for n = 1:720, %Calculate and Set Heading/Location XX = [obj.robot.x;obj.robot.y]; store_data(XX); if n == 120, DATA.path end %Update Position headingChange = navigate(n); obj.robot.updatePosition(headingChange); obj.landmarks.updatePerspective(obj.robot.heading, obj.robot.x, obj.robot.y); %Animate %"UNCOMMENT ME" set(l.pth, 'xdata', DATA.path(1,1:DATA.i), 'ydata', DATA.path(2,1:DATA.i)); set(l.lm,'XData',obj.landmarks.apparentPositions(:,1),'YData',obj.landmarks.apparentPositions(:,2)); rectangle('Position',[-2,-2,4,4]); drawnow This is the classdef for landmarks classdef landmarks <handle properties fixedPositions; %# positions in a fixed coordinate system. [ x, y ] mapSize; %Map Size. Value is side of square x; y; heading; headingChange; end properties (Dependent) apparentPositions end methods function obj = landmarks(mapSize, numberOfTrees) obj.mapSize = mapSize; obj.fixedPositions = obj.mapSize * rand([numberOfTrees, 2]) .* sign(rand([numberOfTrees, 2]) - 0.5); end function apparent = get.apparentPositions(obj) currentPosition = [obj.x ; obj.y]; apparent = bsxfun(@minus,(obj.fixedPositions)',currentPosition)'; apparent = ([cosd(obj.heading) -sind(obj.heading) ; sind(obj.heading) cosd(obj.heading)] * (apparent)')'; end function updatePerspective(obj,tempHeading,tempX,tempY) obj.heading = tempHeading; obj.x = tempX; obj.y = tempY; end end end To me, this is how I understand things. I created a figure l.lm that has about 100 xy points. I can rotate this figure by using set(l.lm,'XData',obj.landmarks.apparentPositions(:,1),'YData',obj.landmarks.apparentPositions(:,2)); When I do that, things work. When I try to plot a second group of XY points, stored in DATA.path, it craps out and I can't figure out why.

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  • EF Code first + Delete Child Object from Parent?

    - by ebb
    I have a one-to-many relationship between my table Case and my other table CaseReplies. I'm using EF Code First and now wants to delete a CaseReply from a Case object, however it seems impossible to do such thing because it just tries to remove the CaseId from the specific CaseReply record and not the record itself.. short: Case just removes the relationship between itself and the CaseReply.. it does not delete the CaseReply. My code: // Case.cs (Case Object) public class Case { [Key] public int Id { get; set; } public string Topic { get; set; } public string Message { get; set; } public DateTime Date { get; set; } public Guid UserId { get; set; } public virtual User User { get; set; } public virtual ICollection<CaseReply> Replies { get; set; } } // CaseReply.cs (CaseReply Object) public class CaseReply { [Key] public int Id { get; set; } public string Message { get; set; } public DateTime Date { get; set; } public int CaseId { get; set; } public Guid UserId { get; set; } public virtual User User { get; set; } public virtual Case Case { get; set; } } // RepositoryBase.cs public class RepositoryBase<T> : IRepository<T> where T : class { public IDbContext Context { get; private set; } public IDbSet<T> ObjectSet { get; private set; } public RepositoryBase(IDbContext context) { Contract.Requires(context != null); Context = context; if (context != null) { ObjectSet = Context.CreateDbSet<T>(); if (ObjectSet == null) { throw new InvalidOperationException(); } } } public IRepository<T> Remove(T entity) { ObjectSet.Remove(entity); return this; } public IRepository<T> SaveChanges() { Context.SaveChanges(); return this; } } // CaseRepository.cs public class CaseRepository : RepositoryBase<Case>, ICaseRepository { public CaseRepository(IDbContext context) : base(context) { Contract.Requires(context != null); } public bool RemoveCaseReplyFromCase(int caseId, int caseReplyId) { Case caseToRemoveReplyFrom = ObjectSet.Include(x => x.Replies).FirstOrDefault(x => x.Id == caseId); var delete = caseToRemoveReplyFrom.Replies.FirstOrDefault(x => x.Id == caseReplyId); caseToRemoveReplyFrom.Replies.Remove(delete); return Context.SaveChanges() >= 1; } } Thanks in advance.

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  • Explicitly instantiating a generic member function of a generic structure

    - by Dennis Zickefoose
    I have a structure with a template parameter, Stream. Within that structure, there is a function with its own template parameter, Type. If I try to force a specific instance of the function to be generated and called, it works fine, if I am in a context where the exact type of the structure is known. If not, I get a compile error. This feels like a situation where I'm missing a typename, but there are no nested types. I suspect I'm missing something fundamental, but I've been staring at this code for so long all I see are redheads, and frankly writing code that uses templates has never been my forte. The following is the simplest example I could come up with that illustrates the issue. #include <iostream> template<typename Stream> struct Printer { Stream& str; Printer(Stream& str_) : str(str_) { } template<typename Type> Stream& Exec(const Type& t) { return str << t << std::endl; } }; template<typename Stream, typename Type> void Test1(Stream& str, const Type& t) { Printer<Stream> out = Printer<Stream>(str); /****** vvv This is the line the compiler doesn't like vvv ******/ out.Exec<bool>(t); /****** ^^^ That is the line the compiler doesn't like ^^^ ******/ } template<typename Type> void Test2(const Type& t) { Printer<std::ostream> out = Printer<std::ostream>(std::cout); out.Exec<bool>(t); } template<typename Stream, typename Type> void Test3(Stream& str, const Type& t) { Printer<Stream> out = Printer<Stream>(str); out.Exec(t); } int main() { Test2(5); Test3(std::cout, 5); return 0; } As it is written, gcc-4.4 gives the following: test.cpp: In function 'void Test1(Stream&, const Type&)': test.cpp:22: error: expected primary-expression before 'bool' test.cpp:22: error: expected ';' before 'bool' Test2 and Test3 both compile cleanly, and if I comment out Test1 the program executes, and I get "1 5" as I expect. So it looks like there's nothing wrong with the idea of what I want to do, but I've botched something in the implementation. If anybody could shed some light on what I'm overlooking, it would be greatly appreciated.

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  • seg fault caused by malloc and sscanf in a function

    - by Framester
    Hi, I want to open a text file (see below), read the first int in every line and store it in an array, but I get an segmentation fault. I got rid of all gcc warnings, I read through several tutorials I found on the net and searched stackoverflow for solutions, but I could't make out, what I am doing wrong. It works when I have everything in the main function (see example 1), but not when I transfer it to second function (see example 2 further down). In example 2 I get, when I interpret gdb correctly a seg fault at sscanf (line,"%i",classes[i]);. I'm afraid, it could be something trivial, but I already wasted one day on it. Thanks in advance. [Example 1] Even though that works with everything in main: #include<stdio.h> #include<stdlib.h> #include<string.h> const int LENGTH = 1024; int main() { char *filename="somedatafile.txt"; int *classes; int lines; FILE *pfile = NULL; char line[LENGTH]; pfile=fopen(filename,"r"); int numlines=0; char *p; while(fgets(line,LENGTH,pfile)){ numlines++; } rewind(pfile); classes=(int *)malloc(numlines*sizeof(int)); if(classes == NULL){ printf("\nMemory error."); exit(1); } int i=0; while(fgets(line,LENGTH,pfile)){ printf("\n"); p = strtok (line," "); p = strtok (NULL, ", "); sscanf (line,"%i",&classes[i]); i++; } fclose(pfile); return 1; } [Example 2] This does not with the functionality transfered to a function: #include<stdio.h> #include<stdlib.h> #include<string.h> const int LENGTH = 1024; void read_data(int **classes,int *lines, char *filename){ FILE *pfile = NULL; char line[LENGTH]; pfile=fopen(filename,"r"); int numlines=0; char *p; while(fgets(line,LENGTH,pfile)){ numlines++; } rewind(pfile); * classes=(int *)malloc(numlines*sizeof(int)); if(*classes == NULL){ printf("\nMemory error."); exit(1); } int i=0; while(fgets(line,LENGTH,pfile)){ printf("\n"); p = strtok (line," "); p = strtok (NULL, ", "); sscanf (line,"%i",classes[i]); i++; } fclose(pfile); *lines=numlines; } int main() { char *filename="somedatafile.txt"; int *classes; int lines; read_data(&classes, &lines,filename) ; for(int i=0;i<lines;i++){ printf("\nclasses[i]=%i",classes[i]); } return 1; } [Content of somedatafile.txt] 50 21 77 0 28 0 27 48 22 2 55 0 92 0 0 26 36 92 56 4 53 0 82 0 52 -5 29 30 2 1 37 0 76 0 28 18 40 48 8 1 37 0 79 0 34 -26 43 46 2 1 85 0 88 -4 6 1 3 83 80 5 56 0 81 0 -4 11 25 86 62 4 55 -1 95 -3 54 -4 40 41 2 1 53 8 77 0 28 0 23 48 24 4 37 0 101 -7 28 0 64 73 8 1 ...

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  • C++ template function specialization using TCHAR on Visual Studio 2005

    - by Eli
    I'm writing a logging class that uses a templatized operator<< function. I'm specializing the template function on wide-character string so that I can do some wide-to-narrow translation before writing the log message. I can't get TCHAR to work properly - it doesn't use the specialization. Ideas? Here's the pertinent code: // Log.h header class Log { public: template <typename T> Log& operator<<( const T& x ); template <typename T> Log& operator<<( const T* x ); template <typename T> Log& operator<<( const T*& x ); ... } template <typename T> Log& Log::operator<<( const T& input ) { printf("ref"); } template <typename T> Log& Log::operator<<( const T* input ) { printf("ptr"); } template <> Log& Log::operator<<( const std::wstring& input ); template <> Log& Log::operator<<( const wchar_t* input ); And the source file // Log.cpp template <> Log& Log::operator<<( const std::wstring& input ) { printf("wstring ref"); } template <> Log& Log::operator<<( const wchar_t* input ) { printf("wchar_t ptr"); } template <> Log& Log::operator<<( const TCHAR*& input ) { printf("tchar ptr ref"); } Now, I use the following test program to exercise these functions // main.cpp - test program int main() { Log log; log << "test 1"; log << L"test 2"; std::string test3( "test3" ); log << test3; std::wstring test4( L"test4" ); log << test4; TCHAR* test5 = L"test5"; log << test4; } Running the above tests reveals the following: // Test results ptr wchar_t ptr ref wstring ref ref Unfortunately, that's not quite right. I'd really like the last one to be "TCHAR", so that I can convert it. According to Visual Studio's debugger, the when I step in to the function being called in test 5, the type is wchar_t*& - but it's not calling the appropriate specialization. Ideas? I'm not sure if it's pertinent or not, but this is on a Windows CE 5.0 device.

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  • Var null and not an object when using document.getElementById

    - by Dean
    Hi, I'm doing some work in HTML and JQuery. I have a problem of my textarea and submit button not appearing after the radio button is selected. My HTML looks like this: <html> <head><title>Publications Database | Which spotlight for Publications</title> <script type="text/javascript" src="./jquery.js"></script> <script src="./addSpotlight.js" type="text/javascript" charset="utf-8"></script> </head> <body> <div class="wrapper"> <div class="header"> <div class="headerText">Which spotlight for Publications</div> </div> <div class="mainContent"> <p>Please select the publication that you would like to make the spotlight of this month:</p> <form action="addSpotlight" method="POST" id="form" name="form"> <div class="div29" id="div29"><input type="radio" value="29" name="publicationIDs" >A System For Dynamic Server Allocation in Application Server Clusters, IEEE International Symposium on Parallel and Distributed Processsing with Applications, 2008 </div> <div class="div30" id="div30"><input type="radio" value="30" name="publicationIDs" >Analysing BitTorrent's Seeding Strategies, 7th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC-09), 2009 </div> <div class="div31" id="div31"><input type="radio" value="31" name="publicationIDs" >The Effect of Server Reallocation Time in Dynamic Resource Allocation, UK Performance Engineering Workshop 2009, 2009 </div> <div class="div32" id="div32"><input type="radio" value="32" name="publicationIDs" >idk, hello, 1992 </div> <div class="div33" id="div33"><input type="radio" value="33" name="publicationIDs" >sad, safg, 1992 </div> <div class="abstractWriteup" id="abstractWriteup"><textarea name="abstract"></textarea> <input type="submit" value="Add Spotlight"></div> </form> </div> </div> </body> </html> My javascript looks like this: $(document).ready( function() { $('.abstractWriteup').hide(); addAbstract(); }); function addAbstract() { var abstractWU = document.getElementById('.abstractWriteup'); $("input[name='publicationIDs']").change(function() { var abstractWU = document.getElementById('.abstractWriteup'); var classNameOfSelected = $("input[name='publicationIDs']").val(); var radioSelected = document.getElementById("div"+classNameOfSelected); var parentDiv = radioSelected.parentNode; parentDiv.insertBefore(radioSelected, abstractWU.nextSibling); $('.abstractWriteup').show(); });}; I have developed this by using Node#insertBefore. When I have had it working it has been rearranging the radio buttons. Thanks in Advance Dean

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  • Only root object on request is deserialized when using Message.GetBody<>

    - by user324627
    I am attempting to create a wcf service that accepts any input (Action="*") and then deserialize the message after determining its type. For the purposes of testing deserialization I am currently hard-coding the type for the test service. I get no errors from the deserialization process, but only the outer object is populated after deserialization occurs. All inner fields are null. I can process the same request against the original wcf service successfully. I am deserializing this way, where knownTypes is a type list of expected types: DataContractSerializer ser = new DataContractSerializer(new createEligibilityRuleSet ().GetType(), knownTypes); createEligibilityRuleSet newReq = buf.CreateMessage().GetBody<createEligibilityRuleSet>(ser); Here is the class and sub-classes of the request object. These classes are generated by svcutil using a top down approach from an existing wsdl. I have tried replacing the XmlTypeAttributes with DataContracts and the XmlElements with DataMembers with no difference. It is the instance of CreateEligibilityRuleSetSvcRequest on the createEligibilityRuleSet object that is null. I have included the request retrieved from the request at the bottom /// <remarks/> [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true, Namespace = "http://RulesEngineServicesLibrary/RulesEngineServices")] public partial class createEligibilityRuleSet { private CreateEligibilityRuleSetSvcRequest requestField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, IsNullable = true, Order = 0)] public CreateEligibilityRuleSetSvcRequest request { get { return this.requestField; } set { this.requestField = value; } } } /// <remarks/> [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://RulesEngineServicesLibrary")] public partial class CreateEligibilityRuleSetSvcRequest : RulesEngineServicesSvcRequest { private string requestField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, Order = 0)] public string request { get { return this.requestField; } set { this.requestField = value; } } } [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateEligibilityRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(ApplyMemberEligibilitySvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateCompletionCriteriaRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CopyRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(DeleteRuleSetByIDSvcRequest))] [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://RulesEngineServicesLibrary")] public partial class RulesEngineServicesSvcRequest : ServiceRequest { } /// <remarks/> [System.Xml.Serialization.XmlIncludeAttribute(typeof(RulesEngineServicesSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateEligibilityRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(ApplyMemberEligibilitySvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateCompletionCriteriaRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CopyRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(DeleteRuleSetByIDSvcRequest))] [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://FELibrary")] public partial class ServiceRequest { private string applicationIdField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, Order = 0)] public string applicationId { get { return this.applicationIdField; } set { this.applicationIdField = value; } } } Request from client comes on Message body as below. Retrieved from Message at runtime. <soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:rul="http://RulesEngineServicesLibrary/RulesEngineServices"> <soap:Header/> <soap:Body> <rul:createEligibilityRuleSet> <request> <applicationId>test</applicationId> <request>Perf Rule Set1</request> </request> </rul:createEligibilityRuleSet> </soap:Body> </soap:Envelope>

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  • Reading serialised object from file

    - by nico
    Hi everyone. I'm writing a little Java program (it's an ImageJ plugin, but the problem is not specifically ImageJ related) and I have some problem, most probably due to the fact that I never really programmed in Java before... So, I have a Vector of Vectors and I'm trying to save it to a file and read it. The variable is defined as: Vector <Vector <myROI> > ROIs = new Vector <Vector <myROI> >(); where myROI is a class that I previously defined. Now, to write the vector to a file I use: void saveROIs() { SaveDialog save = new SaveDialog("Save ROIs...", imp.getTitle(), ".xroi"); String name = save.getFileName(); if (name == null) return; String dir = save.getDirectory(); try { FileOutputStream fos = new FileOutputStream(dir+name); ObjectOutputStream oos = new ObjectOutputStream(fos); oos.writeObject(ROIs); oos.close(); } catch (Exception e) { IJ.log(e.toString()); } } This correctly generates a binary file containing (I suppose) the object ROIs. Now, I use a very similar code to read the file: void loadROIs() { OpenDialog open = new OpenDialog("Load ROIs...", imp.getTitle(), ".xroi"); String name = open.getFileName(); if (name == null) return; String dir = open.getDirectory(); try { FileInputStream fin = new FileInputStream(dir+name); ObjectInputStream ois = new ObjectInputStream(fin); ROIs = (Vector <Vector <myROI> >) ois.readObject(); // This gives error ois.close(); } catch (Exception e) { IJ.log(e.toString()); } } But this function does not work. First, I get a warning: warning: [unchecked] unchecked cast found : java.lang.Object required: java.util.Vector<java.util.Vector<myROI>> ROIs = (Vector <Vector <myROI> >) ois.readObject(); ^ I Googled for that and see that I can suppress by prepending @SuppressWarnings("unchecked"), but this just makes things worst, as I get an error: <identifier> expected ROIs = (Vector <Vector <myROI> >) ois.readObject(); ^ In any case, if I omit @SuppressWarnings and ignore the warning, the object is not read and an exception is thrown java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: myROI Again Google tells me myROI needs to implements Serializable. I tried just adding implements Serializable to the class definition, but it is not sufficient. Can anyone give me some hints on how to procede in this case? Also, how to get rid of the typecast warning?

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  • problem with PHP class function ()

    - by lusey
    hello this is my first question here and i hope you can help me .. I am trying to find a soloution of the towers of hanoi problem by three search ways (BFS-DFS-IDS) so I use "state" class whitch defined by 5 variables as here : class state { var $tower1 = array(); var $tower2 = array(); var $tower3 = array(); var $depth; var $neighbors = array(); and it also has many function one of them is getneighbors() which supposed to fill the array $neighbors with state neighbors and they are from the type "state" and here is the function : function getneighbors () { $temp=$this->copy(); $neighbor1= $this->copy(); $neighbor2= $this->copy(); $neighbor3= $this->copy(); $neighbor4= $this->copy(); $neighbor5= $this->copy(); $neighbor6= $this->copy(); if(!Empty($temp->tower1)) { if(!Empty($neighbor1->tower2)) { if(end($neighbor1->tower1) < end($neighbor1->tower2)) { array_unshift($neighbor1->tower2,array_pop($neighbor1->tower1)); array_push($neighbors,$neighbor1); }} else { array_unshift($neighbor1->tower2, array_pop($neighbor1->tower1)); array_push($neighbors,$neighbor1); } if(!Empty($neighbor2->tower3)) { if(end($neighbor2->tower1) < end($neighbor2->tower3)) { array_unshift($neighbor2->tower3, array_pop($neighbor2->tower1)); array_push($neighbors,$neighbor2); }} else { array_unshift($neighbor2->tower3,array_shift($neighbor2->tower1)); array_push($neighbors,$neighbor2); } } if(!Empty($temp->tower2)) { if(!Empty($neighbor3->tower1)) { if(end($neighbor3->tower2) < end($neighbor3->tower1)) { array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2)); array_push($neighbors,$neighbor3); } } else { array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2)); array_push($neighbors,$neighbor3); } if(!Empty($neighbor4->tower3)) { if(end($neighbor4->tower2) < end($neighbor4->tower3)) { array_unshift($neighbor4->tower1,array_shift($neighbor4->tower2)); array_push($neighbors,$neighbor4); } } else{ array_unshift($neighbor4->tower3,array_shift($neighbor4->tower2)); array_push($neighbors,$neighbor4); } } if(!Empty($temp->tower3)) { if(!Empty($neighbor5->tower1)) { if(end($neighbor5->tower3) < end($neighbor5->tower1)) {array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3)); array_push($neighbors,$neighbor5); } } else{ array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3)); array_push($neighbors,$neighbor5);} if(!Empty($neighbor6->tower2)) { if(end($neighbor6->tower3) < end($neighbor6->tower2)) { array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3)); array_push($neighbors,$neighbor6); }} else{ array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3)); array_push($neighbors,$neighbor6);} } return $neighbors; } note that toString and equals and copy are defined too now the problem is that when I call getneighbors() it returns an empty $neighbors array can you pleas tell me the problem ?

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  • Adding view cart function

    - by user228390
    Hey guys need some help in adding a view cart button but I'm stuck not sure how to code it. any help? The way I have coded it is that when a user clicks 'add item' they will get a alert box with info about the total price but I want that to appear in the HTML file but only once I have clicked on 'view cart' and I need it to be in a table format with info about the name, sum, price of the items and total. any ideas how I can do this? here is my javascript var f,d,str,items,qnts,price,bag,total; function cart(){ f=document.forms[0]; d=f.getElementsByTagName('div'); var items=[];var qnts=[];price=[];bag=[] for(i=0,e=0;i<d.length;i++){ items[i]=d[i].getElementsByTagName('b')[0].innerHTML; qnts[i]=d[i].getElementsByTagName('select')[0].value; str=d[i].getElementsByTagName('p')[1].innerHTML; priceStart(str,i); if(qnts[i]!=0){bag.push(new Array()); ib=bag[bag.length-1]; ib.push(items[i]);ib.push(qnts[i]);ib.push(price[i]);ib.push(qnts[i]*price[i]);} } if(bag.length>0){ total=bag[0][3]; if(bag.length>1){for(t=1;t<bag.length;t++){total+=bag[t][3]}} alert(bag.join('\n')+'\n----------------\ntotal='+total) } } function priceStart(str,inx){for(j=0;j<str.length;j++){if(str.charAt(j)!=' ' && !isNaN(str.charAt(j))){priceEnd(j,str,inx);return }}} function priceEnd(j,str,inx){for(k=str.length;k>j;k--){if(str.charAt(k)!=' ' && !isNaN(str.charAt(k))){price[inx]=str.substring(j,k);return }}} and my HTML <script type="text/javascript" src="cart.js" /> </script> <link rel="stylesheet" type="text/css" href="shopping_cart.css" /> <title> A title </title> </head> <body> <form name="form1" method="post" action="data.php" > <div id="product1"> <p id="title1"><b>Star Wars Tie Interceptor</b></p> <img src="images/DS.jpg" /> <p id="price1">Price £39.99</p> <p><b>Qty</b></p> <select name="qty"> <option value="0">0</option> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> </select> <input type="button" value="Add to cart" onclick="cart()" /> </div>

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  • Cannot pull correct data from a Javascript array into an HTML form

    - by Isaac
    I am trying to return the description value of the corresponding author name and book title(that are typed in the text boxes). The problem is that the first description displays in the text area no matter what. <h1>Bookland</h1> <div id="bookinfo"> Author name: <input type="text" id="authorname" name="authorname"></input><br /> Book Title: <input type="text" id="booktitle" name="booktitle"></input><br /> <input type="button" value="Find book" id="find"></input> <input type="button" value="Clear Info" id="clear"></input><br /> <textarea rows="15" cols="30" id="destin"></textarea> </div> JavaScript: var bookarray = [{Author: "Thomas Mann", Title: "Death in Venice", Description: "One of the most famous literary works of the twentieth century, this novella embodies" + "themes that preoccupied Thomas Mann in much of his work:" + "the duality of art and life, the presence of death and disintegration in the midst of existence," + "the connection between love and suffering and the conflict between the artist and his inner self." }, {Author: "James Joyce", Title: "A portrait of the artist as a young man", Description: "This work displays an unusually perceptive view of British society in the early 20th century." + "It is a social comedy set in Florence, Italy, and Surrey, England." + "Its heroine, Lucy Honeychurch, struggling against straitlaced Victorian attitudes of arrogance, narroe mindedness and sobbery, falls in love - while on holiday in Italy - with the socially unsuitable George Emerson." }, {Author: "E. M. Forster", Title: "A room with a view", Description: "This book is a fictional re-creation of the Irish writer'sown life and early environment." + "The experiences of the novel's young hero,unfold in astonishingly vivid scenes that seem freshly recalled from life" + "and provide a powerful portrait of the coming of age of a young man ofunusual intelligence, sensitivity and character. " }, {Author: "Isabel Allende", Title: "The house of spirits", Description: "Allende describes the life of three generations of a prominent family in Chile and skillfully combines with this all the main historical events of the time, up until Pinochet's dictatorship." }, {Author: "Isabel Allende", Title: "Of love and shadows", Description: "The whole world of Irene Beltran, a young reporter in Chile at the time of the dictatorship, is destroyed when" + "she discovers a series of killings carried out by government soldiers." + "With the help of a photographer, Francisco Leal, and risking her life, she tries to come up with evidence against the dictatorship." }] function searchbook(){ for(i=0; i &lt; bookarray.length; i++){ if ((document.getElementById("authorname").value &amp; document.getElementById("booktitle").value ) == (bookarray[i].Author &amp; bookarray[i].Title)){ document.getElementById("destin").value =bookarray[i].Description return bookarray[i].Description } else { return "Not Found!" } } } document.getElementById("find").addEventListener("click", searchbook, false)

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  • How much abstraction is too much?

    - by Daniel Bingham
    In an Object Oriented Program: How much abstraction is too much? How much is just right? I have always been a nuts and bolts kind of guy. I understood the concept behind high levels of encapsulation and abstraction, but always felt instinctively that adding too much would just confuse the program. I always tried to shoot for an amount of abstraction that left no empty classes or layers. And where in doubt, instead of adding a new layer to the hierarchy, I would try and fit something into the existing layers. However, recently I've been encountering more highly abstracted systems. Systems where everything that could require a representation later in the hierarchy gets one up front. This leads to a lot of empty layers, which at first seems like bad design. However, on second thought I've come to realize that leaving those empty layers gives you more places to hook into in the future with out much refactoring. It leaves you greater ability to add new functionality on top of the old with out doing nearly as much work to adjust the old. The two risks of this seem to be that you could get the layers you need wrong. In this case one would wind up still needing to do substantial refactoring to extend the code and would still have a ton of never used layers. But depending on how much time you spend coming up with the initial abstractions, the chance of screwing it up, and the time that could be saved later if you get it right - it may still be worth it to try. The other risk I can think of is the risk of over doing it and never needing all the extra layers. But is that really so bad? Are extra class layers really so expensive that it is much of a loss if they are never used? The biggest expense and loss here would be time that is lost up front coming up with the layers. But much of that time still might be saved later when one can work with the abstracted code rather than more low level code. So when is it too much? At what point do the empty layers and extra "might need" abstractions become overkill? How little is too little? Where's the sweet spot? Are there any dependable rules of thumb you've found in the course of your career that help you judge the amount of abstraction needed?

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  • Strategy pattern and "action" classes explosion

    - by devoured elysium
    Is it bad policy to have lots of "work" classes(such as Strategy classes), that only do one thing? Let's assume I want to make a Monster class. Instead of just defining everything I want about the monster in one class, I will try to identify what are its main features, so I can define them in interfaces. That will allow to: Seal the class if I want. Later, other users can just create a new class and still have polymorphism by means of the interfaces I've defined. I don't have to worry how people (or myself) might want to change/add features to the base class in the future. All classes inherit from Object and they implement inheritance through interfaces, not from mother classes. Reuse the strategies I'm using with this monster for other members of my game world. Con: This model is rigid. Sometimes we would like to define something that is not easily achieved by just trying to put together this "building blocks". public class AlienMonster : IWalk, IRun, ISwim, IGrowl { IWalkStrategy _walkStrategy; IRunStrategy _runStrategy; ISwimStrategy _swimStrategy; IGrowlStrategy _growlStrategy; public Monster() { _walkStrategy = new FourFootWalkStrategy(); ...etc } public void Walk() { _walkStrategy.Walk(); } ...etc } My idea would be next to make a series of different Strategies that could be used by different monsters. On the other side, some of them could also be used for totally different purposes (i.e., I could have a tank that also "swims"). The only problem I see with this approach is that it could lead to a explosion of pure "method" classes, i.e., Strategy classes that have as only purpose make this or that other action. In the other hand, this kind of "modularity" would allow for high reuse of stratagies, sometimes even in totally different contexts. What is your opinion on this matter? Is this a valid reasoning? Is this over-engineering? Also, assuming we'd make the proper adjustments to the example I gave above, would it be better to define IWalk as: interface IWalk { void Walk(); } or interface IWalk { IWalkStrategy WalkStrategy { get; set; } //or something that ressembles this } being that doing this I wouldn't need to define the methods on Monster itself, I'd just have public getters for IWalkStrategy (this seems to go against the idea that you should encapsulate everything as much as you can!) Why? Thanks

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  • Data denormalization and C# objects DB serialization

    - by Robert Koritnik
    I'm using a DB table with various different entities. This means that I can't have an arbitrary number of fields in it to save all kinds of different entities. I want instead save just the most important fields (dates, reference IDs - kind of foreign key to various other tables, most important text fields etc.) and an additional text field where I'd like to store more complete object data. the most obvious solution would be to use XML strings and store those. The second most obvious choice would be JSON, that usually shorter and probably also faster to serialize/deserialize... And is probably also faster. But is it really? My objects also wouldn't need to be strictly serializable, because JsonSerializer is usually able to serialize anything. Even anonymous objects, that may as well be used here. What would be the most optimal solution to solve this problem? Additional info My DB is highly normalised and I'm using Entity Framework, but for the purpose of having external super-fast fulltext search functionality I'm sacrificing a bit DB denormalisation. Just for the info I'm using SphinxSE on top of MySql. Sphinx would return row IDs that I would use to fast query my index optimised conglomerate table to get most important data from it much much faster than querying multiple tables all over my DB. My table would have columns like: RowID (auto increment) EntityID (of the actual entity - but not directly related because this would have to point to different tables) EntityType (so I would be able to get the actual entity if needed) DateAdded (record timestamp when it's been added into this table) Title Metadata (serialized data related to particular entity type) This table would be indexed with SPHINX indexer. When I would search for data using this indexer I would provide a series of EntityIDs and a limit date. Indexer would have to return a very limited paged amount of RowIDs ordered by DateAdded (descending). I would then just join these RowIDs to my table and get relevant results. So this won't actually be full text search but a filtering search. Getting RowIDs would be very fast this way and getting results back from the table would be much faster than comparing EntityIDs and DateAdded comparisons even though they would be properly indexed.

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  • Is the design notion of layers contrived?

    - by Bruce
    Hi all I'm reading through Eric Evans' awesome work, Domain-Driven Design. However, I can't help feeling that the 'layers' model is contrived. To expand on that statement, it seems as if it tries to shoe-horn various concepts into a specific, neat model, that of layers talking to each other. It seems to me that the layers model is too simplified to actually capture the way that (good) software works. To expand further: Evans says: "Partition a complex program into layers. Develop a design within each layer that is cohesive and that depends only on the layers below. Follow standard architectural patterns to provide loose coupling to the layers above." Maybe I'm misunderstanding what 'depends' means, but as far as I can see, it can either mean a) Class X (in the UI for example) has a reference to a concrete class Y (in the main application) or b) Class X has a reference to a class Y-ish object providing class Y-ish services (ie a reference held as an interface). If it means (a), then this is clearly a bad thing, since it defeats re-using the UI as a front-end to some other application that provides Y-ish functionality. But if it means (b), then how is the UI any more dependent on the application, than the application is dependent on the UI? Both are decoupled from each other as much as they can be while still talking to each other. Evans' layer model of dependencies going one way seems too neat. First, isn't it more accurate to say that each area of the design provides a module that is pretty much an island to itself, and that ideally all communication is through interfaces, in a contract-driven/responsibility-driven paradigm? (ie, the 'dependency only on lower layers' is contrived). Likewise with the domain layer talking to the database - the domain layer is as decoupled (through DAO etc) from the database as the database is from the domain layer. Neither is dependent on the other, both can be swapped out. Second, the idea of a conceptual straight line (as in from one layer to the next) is artificial - isn't there more a network of intercommunicating but separate modules, including external services, utility services and so on, branching off at different angles? Thanks all - hoping that your responses can clarify my understanding on this..

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  • pointers to functions

    - by DevAno1
    I have two basic Cpp tasks, but still I have problems with them. First is to write functions mul1,div1,sub1,sum1, taking ints as arguments and returning ints. Then I need to create pointers ptrFun1 and ptrFun2 to functions mul1 and sum1, and print results of using them. Problem starts with defining those pointers. I thought I was doing it right, but devcpp gives me errors in compilation. #include <iostream> using namespace std; int mul1(int a,int b) { return a * b; } int div1(int a,int b) { return a / b; } int sum1(int a,int b) { return a + b; } int sub1(int a,int b) { return a - b; } int main() { int a=1; int b=5; cout << mul1(a,b) << endl; cout << div1(a,b) << endl; cout << sum1(a,b) << endl; cout << sub1(a,b) << endl; int *funPtr1(int, int); int *funPtr2(int, int); funPtr1 = sum1; funPtr2 = mul1; cout << funPtr1(a,b) << endl; cout << funPtr2(a,b) << endl; system("PAUSE"); return 0; } 38 assignment of function int* funPtr1(int, int)' 38 cannot convertint ()(int, int)' to `int*()(int, int)' in assignment Task 2 is to create array of pointers to those functions named tabFunPtr. How to do that ?

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  • How can I model the data in a multi-language data editor in WPF with MVVM?

    - by Patrick Szalapski
    Are there any good practices to follow when designing a model/ViewModel to represent data in an app that will view/edit that data in multiple languages? Our top-level class--let's call it Course--contains several collection properties, say Books and TopicsCovered, which each might have a collection property among its data. For example, the data needs to represent course1.Books.First().Title in different languages, and course1.TopicsCovered.First().Name in different languages. We want a app that can edit any of the data for one given course in any of the available languages--as well as edit non-language-specific data, perhaps the Author of a Book (i.e. course1.Books.First().Author). We are having trouble figuring out how best to set up the model to enable binding in the XAML view. For example, do we replace (in the single-language model) each String with a collection of LanguageSpecificString instances? So to get the author in the current language: course1.Books.First().Author.Where(Function(a) a.Language = CurrentLanguage).SingleOrDefault If we do that, we cannot easily bind to any value in one given language, only to the collection of language values such as in an ItemsControl. <TextBox Text={Binding Author.???} /> <!-- no way to bind to the current language author --> Do we replace the top-level Course class with a collection of language-specific Courses? So to get the author in the current language: course1.GetLanguage(CurrentLanguage).Books.First.Author If we do that, we can only easily work with one language at a time; we might want a view to show one language and let the user edit the other. <TextBox Text={Binding Author} /> <!-- good --> <TextBlock Text={Binding ??? } /> <!-- no way to bind to the other language author --> Also, that has the disadvantage of not representing language-neutral data as such; every property (such as Author) would seem to be in multiple languages. Even non-string properties would be in multiple languages. Is there an option in between those two? Is there another way that we aren't thinking of? I realize this is somewhat vague, but it would seem to be a somewhat common problem to design for. Note: This is not a question about providing a multilingual UI, but rather about actually editing multi-language data in a flexible way.

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