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  • C# myths about best practices?

    - by TheMachineCharmer
    My colleague keeps telling me of the things listed in comments. I am confused. Can somebody please demystify these things for me? class Bar { private int _a; public int A { get { return _a; } set { _a = value; } } private Foo _objfoo; public Foo OFoo { get { return _objfoo; } set { _objfoo = value; } } public Bar(int a, Foo foo) { // this is a bad idea A = a; OFoo = foo; } // MYTHS private void Method() { this.A //1 - this._a //2 - use this when inside the class e.g. if(this._a == 2) A //3 - use this outside the class e.g. barObj.A _a //4 - // Not using this.xxx creates threading issues. } } class Foo { // implementation }

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  • more ruby way of doing project euler #2

    - by aharon
    I'm trying to learn Ruby, and am going through some of the Project Euler problems. I solved two as such: def fib(n) return n if n < 2 vals = [0, 1] n.times do vals.push(vals[-1]+vals[-2]) end return vals.last end i = 1 s = 0 while((v = fib(i)) < 4_000_000) s+=v if v%2==0 i+=1 end puts s While that works, it seems not very ruby-ish—I couldn't come up with any good purely Ruby answer like I could with the first one ( puts ( (0..999).inject{ |sum, n| n%3==0||n%5==0 ? sum : sum+n } )).

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  • Test for empty jQuery selection result

    - by fsb
    Say I do var s = $('#something'); and next I want to test if jQuery found #something, i.e. I want to test if s is empty. I could use my trusty isempty() on it: function isempty(o) { for ( var i in o ) return false; return true; } Or since jQuery objects are arrays, I suppose I could test s.length. But neither seem quite in the idiom of jQuery, not very jQueryesque. What do you suggest?

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  • Optimize conditional operators branching in C#

    - by abatishchev
    Hello. I have next code: return this.AllowChooseAny.Value ? radioSpecific.Checked ? UserManager.CurrentUser.IsClient ? txtSubject.Text : subjectDropDownList.SelectedItem.Text : String.Empty : UserManager.CurrentUser.IsClient ? txtSubject.Text : subjectDropDownList.SelectedItem.Text; or in less complex form: return any ? specified ? isClient ? textbox : dropdown : empty : isClient ? textbox : dropdown; or in schematic form: | any / \ specified isClient / \ / \ isClient empty textbox dropdown / \ textbox dropdown Evidently I have a duplicated block on two different levels. Is it possible to optimize this code to probably split them to one? Or something like that..

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  • Django Initial for a ManyToMany Field

    - by gramware
    I have a form that edits an instance of my model. I would like to use the form to pass all the values as hidden with an inital values of username defaulting to the logged in user so that it becomes a subscribe form. The problem is that the normal initial={'field':value} doesn't seem to work for manytomany fields. how do i go about it? my views.py @login_required def event_view(request,eventID): user = UserProfile.objects.get(pk=request.session['_auth_user_id']) event = events.objects.get(eventID = eventID) if request.method == 'POST': form = eventsSusbcribeForm( request.POST,instance=event) if form.is_valid(): form.save() return HttpResponseRedirect('/events/') else: form = eventsSusbcribeForm(instance=event) return render_to_response('event_view.html', {'user':user,'event':event, 'form':form},context_instance = RequestContext( request )) my forms.py class eventsSusbcribeForm(forms.ModelForm): eventposter = forms.ModelChoiceField(queryset=UserProfile.objects.all(), widget=forms.HiddenInput()) details = forms.CharField(widget=forms.Textarea(attrs={'cols':'50', 'rows':'5'}),label='Enter Event Description here') date = forms.DateField(widget=SelectDateWidget()) class Meta: model = events exclude = ('deleted') def __init__(self, *args, **kwargs): super(eventsSusbcribeForm, self).__init__(*args, **kwargs) self.fields['username'].initial = (user.id for user in UserProfile.objects.filter())

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  • Using jQuery's animate(), if the clicked on element is "<a href="#" ...> </a>", the fucntion should

    - by Jian Lin
    I was reading jQuery's page for animate() http://api.jquery.com/animate/ Its examples don't mention about if using <a href="#" id="clickme">click me</a> ... $('#clickme').click(function() { $('#someDiv').animate({left: "+=60"}); }) we actually still have to return false like in the old days? $('#clickme').click(function() { $('#someDiv').animate({left: "+=60"}); return false; }) (but then, those examples didn't use a <a> for the "click me"... but used something else. Otherwise the page will jump back to the beginning of the page? Does jQuery have a more elegant or magical way of doing it?

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  • Checked equivalent to IllegalArgumentException?

    - by jv1975oid
    I have a method that takes an enum as a parameter and returns some information dependent on that parameter. However, that enum contains some values which should not be handled, and should raise an error condition. Currently the method throws an IllegalArgumentException but I would like this to be a checked exception to force callers to catch it (and return gracefully, logging an error). Is there something suitable or should I create my own Exception subclass? I'm open to other patterns as well. A reasonable reaction would be that all values of the enum should be handled, but that isn't the case. When a new value is added to the enum, I want to make sure that this method does the right thing - alerting a human is preferable to using some default return value in this case. Thanks for any advice.

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  • On Redirect - Failed to generate a user instance of SQL Server...

    - by Craig Russell
    Hello (this is a long post sorry), I am writing a application in ASP.NET MVC 2 and I have reached a point where I am receiving this error when I connect remotely to my Server. Failed to generate a user instance of SQL Server due to failure in retrieving the user's local application data path. Please make sure the user has a local user profile on the computer. The connection will be closed. I thought I had worked around this problem locally, as I was getting this error in debug when site was redirected to a baseUrl if a subdomain was invalid using this code: protected override void Initialize(RequestContext requestContext) { string[] host = requestContext.HttpContext.Request.Headers["Host"].Split(':'); _siteProvider.Initialise(host, LiveMeet.Properties.Settings.Default["baseUrl"].ToString()); base.Initialize(requestContext); } protected override void OnActionExecuting(ActionExecutingContext filterContext) { if (Site == null) { string[] host = filterContext.HttpContext.Request.Headers["Host"].Split(':'); string newUrl; if (host.Length == 2) newUrl = "http://sample.local:" + host[1]; else newUrl = "http://sample.local"; Response.Redirect(newUrl, true); } ViewData["Site"] = Site; base.OnActionExecuting(filterContext); } public Site Site { get { return _siteProvider.GetCurrentSite(); } } The Site object is returned from a Provider named siteProvider, this does two checks, once against a database containing a list of all available subdomains, then if that fails to find a valid subdomain, or valid domain name, searches a memory cache of reserved domains, if that doesn't hit then returns a baseUrl where all invalid domains are redirected. locally this worked when I added the true to Response.Redirect, assuming a halting of the current execution and restarting the execution on the browser redirect. What I have found in the stack trace is that the error is thrown on the second attempt to access the database. #region ISiteProvider Members public void Initialise(string[] host, string basehost) { if (host[0].Contains(basehost)) host = host[0].Split('.'); Site getSite = GetSites().WithDomain(host[0]); if (getSite == null) { sites.TryGetValue(host[0], out getSite); } _site = getSite; } public Site GetCurrentSite() { return _site; } public IQueryable<Site> GetSites() { return from p in _repository.groupDomains select new Site { Host = p.domainName, GroupGuid = (Guid)p.groupGuid, IsSubDomain = p.isSubdomain }; } #endregion The Linq query ^^^ is hit first, with a filter of WithDomain, the error isn't thrown till the WithDomain filter is attempted. In summary: The error is hit after the page is redirected, so the first iteration is executing as expected (so permissions on the database are correct, user profiles etc) shortly after the redirect when it filters the database query for the possible domain/subdomain of current redirected page, it errors out.

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  • @synthesize with UITabBarController?

    - by fuzzygoat
    I am curious if there is a good reason I should / should not be using @synthesize for the tabBarController below, or does it not matter? @implementation ScramAppDelegate @synthesize window; @synthesize tabBarController; -(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { [self setTabBarController:[[UITabBarController alloc] init]]; [window addSubview:[tabBarController view]]; [window makeKeyAndVisible]; return YES; } -(void)dealloc { [tabBarController release]; [self setTabBarController: nil]; [window release]; [super dealloc]; } OR @implementation ScramAppDelegate @synthesize window; -(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { tabBarController = [[UITabBarController alloc] init]; [window addSubview:[tabBarController view]]; [window makeKeyAndVisible]; return YES; } -(void)dealloc { [tabBarController release]; [window release]; [super dealloc]; } cheers Gary

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  • How to define a static operator<<?

    - by Pietro M
    Is it possible to define a static insertion operator which operates on the static members of a class only? Something like: class MyClass { public: static std::string msg; static MyClass& operator<< (const std::string& token) { msg.append(token); return *this; // error, static } }; alternatively: static MyClass& operator<< (MyClass&, const std::string &token) { MyClass::msg.append(token); return ?; } This is how I would like to use it: MyClass << "message1" << "message2"; Thank you!

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  • Leak in NSScanner category method

    - by jluckyiv
    I created an NSScanner category method that shows a leak in instruments. - (BOOL)scanBetweenPrefix:(NSString *)prefix andSuffix:(NSString *)suffix intoString:(NSString **)value { NSCharacterSet *charactersToBeSkipped = [self charactersToBeSkipped]; [self setCharactersToBeSkipped:nil]; BOOL result = NO; // find the prefix; the scanString method below fails if you don't do this if (![self scanUpToString:prefix intoString:nil]) { MY_LOG(@"Prefix %@ is missing.", prefix); return result; } //scan the prefix and discard [self scanString:prefix intoString:nil]; // scan the important part and save it if ([self scanUpToString:suffix intoString:value]) // this line leaks { result = YES; } [self setCharactersToBeSkipped:charactersToBeSkipped]; return result; } I figure it's the way I'm passing the value to/from the method, but I'm not sure. It's a small leak (32 bytes), but I'd like to do this right if I can. Thanks in advance.

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  • Data not displayed first time in android after copying the file from assets to data folder

    - by Thinkcomplete
    Description I have used the code tip from http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/ to copy a pre-filled data file to the target and handled this in a asynch task Problem : On starting the application it gives error and shuts down first time, starting again without any change it works perfectly fine. So first time after the file is copied, the error comes but after that no issues. Please help Code attached:.. private class CopyDatabase extends AsyncTask<String, Void, Boolean> { private final ProgressDialog dialog = new ProgressDialog(BabyNames.this); protected void onPreExecute() { this.dialog.setMessage("Loading..."); this.dialog.show(); } @Override protected Boolean doInBackground(String... params) { // TODO Auto-generated method stub try { namesDBSQLHelper.createDatabase(); return null; } catch(IOException ioe){ ioe.printStackTrace(); } return null; } protected void onPostExecute(final Boolean success){ if (this.dialog.isShowing()){ this.dialog.dismiss(); } } }

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  • Text box added using javascript doesnot respond as expected to the js attached to it.

    - by Mallika Iyer
    Hello, I am adding a text box using javascript: This is what is generated: <dd id="text3-element" style="width: 350px;"> <input type="text" size="50" id="text3" name="text3" onblur="return getFieldValue(this.id);" value=""> </dd> This is what is present in the getFieldValue function: function getFieldValue(id){ var elem = document.getElementById(id); alert(elem.value); return false; } I'm trying to get the value of the field added using javascript when the value of the filed changes. However, I keep getting the value as 'undefined', in spite of entering text into the newly added text box. This does not happen if the form already has a text box to begin with - i.e., if a text box is not being added via a js function. Anything missing / look wrong here? Thanks!

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  • AJAX Issue, Works in all browsers except IE

    - by Nik
    Alright, this code works in Chrome and FF, but not IE (which is to be expected). Does anyone see anything wrong with this code that would render it useless in IE? var waittime=400; chatmsg = document.getElementById("chatmsg"); room = document.getElementById("roomid").value; sessid = document.getElementById("sessid").value; chatmsg.focus() document.getElementById("chatwindow").innerHTML = "loading..."; document.getElementById("userwindow").innerHTML = "Loading User List..."; var xmlhttp = false; var xmlhttp2 = false; var xmlhttp3 = false; function ajax_read() { if(window.XMLHttpRequest){ xmlhttp=new XMLHttpRequest(); if(xmlhttp.overrideMimeType){ xmlhttp.overrideMimeType('text/xml'); } } else if(window.ActiveXObject){ try{ xmlhttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) { try{ xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } catch(e){ } } } if(!xmlhttp) { alert('Giving up :( Cannot create an XMLHTTP instance'); return false; } xmlhttp.onreadystatechange = function() { if (xmlhttp.readyState==4) { document.getElementById("chatwindow").innerHTML = xmlhttp.responseText; setTimeout("ajax_read()", waittime); } } xmlhttp.open('GET','methods.php?method=r&room=' + room +'',true); xmlhttp.send(null); } function user_read() { if(window.XMLHttpRequest){ xmlhttp3=new XMLHttpRequest(); if(xmlhttp3.overrideMimeType){ xmlhttp3.overrideMimeType('text/xml'); } } else if(window.ActiveXObject){ try{ xmlhttp3=new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) { try{ xmlhttp3=new ActiveXObject("Microsoft.XMLHTTP"); } catch(e){ } } } if(!xmlhttp3) { alert('Giving up :( Cannot create an XMLHTTP instance'); return false; } xmlhttp3.onreadystatechange = function() { if (xmlhttp3.readyState==4) { document.getElementById("userwindow").innerHTML = xmlhttp3.responseText; setTimeout("user_read()", 10000); } } xmlhttp3.open('GET','methods.php?method=u&room=' + room +'',true); xmlhttp3.send(null); } function ajax_write(url){ if(window.XMLHttpRequest){ xmlhttp2=new XMLHttpRequest(); if(xmlhttp2.overrideMimeType){ xmlhttp2.overrideMimeType('text/xml'); } } else if(window.ActiveXObject){ try{ xmlhttp2=new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) { try{ xmlhttp2=new ActiveXObject("Microsoft.XMLHTTP"); } catch(e){ } } } if(!xmlhttp2) { alert('Giving up :( Cannot create an XMLHTTP instance'); return false; } xmlhttp2.open('GET',url,true); xmlhttp2.send(null); } function submit_msg(){ nick = document.getElementById("chatnick").value; msg = document.getElementById("chatmsg").value; document.getElementById("chatmsg").value = ""; ajax_write("methods.php?method=w&m=" + msg + "&n=" + nick + "&room=" + room + "&sessid=" + sessid + ""); } function keyup(arg1) { if (arg1 == 13) submit_msg(); } var intUpdate = setTimeout("ajax_read()", waittime); var intUpdate = setTimeout("user_read()", 0);

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  • Overloading operator>> for case insensitive string

    - by TheSOFan
    Given the definition of ci_string from cpp.reference.com, how would we go about implementing operator? My attempts at it involved std::read, but it doesn't seem to work (that is, gcount() properly counts the number of characters entered, but there is no output) #include <iostream> #include <cctype> #include <string> // ci_string definition goes here std::istream& operator>>(std::istream& in, ci_string& str) { return in.read(&*str.begin(), 4); } int main() { ci_string test_str; std::cin >> test_str; std::cout << test_str; return 0; }

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  • How to set initial checked values of rich tree leaf node.

    - by Ajay99
    Hi, How to set the initial the leaf node values. -----------------------Stations.xml AAAAAAAAAAAA BBBBBBBBBBBB CCCCCCCCCC DDDDDDDDDDDD EEEEEEEEEEEEEE Hall Oates - Kiss On My List David Bowie - Let's Dance Lyn Collins - Think (About It) Kim Carnes - Bette Davis Eyes KC the Sunshine Band - Give It Up //inital check values --------------------Libray.java---------------- public class Library { private TreeNode treeData; private List menus=null; public Library()throws Exception { menus=new ArrayList(); //it's initial selection of the check box vardata.attributes.selection("---key1---); vardata.attributes.selection("---key2---); vardata.attributes.selection("---keyn---); yoursuggestedcode.attribute.selection("key"); //I need your suggestion code. FacesContext context = FacesContext.getCurrentInstance(); treeData = XmlTreeDataBuilder.build(new InputSource(getClass().getResourceAsStream("/Stations.xml"))); } public TreeNode getTreeData() { return treeData; } public void setTreeData(TreeNode treeData) { this.treeData = treeData; } public List getMenus() { return menus; } public void setMenus(List menus) { this.menus = menus; }

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  • PHP: What is an efficient way to parse a text file containing very long lines?

    - by Shaun
    I'm working on a parser in php which is designed to extract MySQL records out of a text file. A particular line might begin with a string corresponding to which table the records (rows) need to be inserted into, followed by the records themselves. The records are delimited by a backslash and the fields (columns) are separated by commas. For the sake of simplicity, let's assume that we have a table representing people in our database, with fields being First Name, Last Name, and Occupation. Thus, one line of the file might be as follows [People] = "\Han,Solo,Smuggler\Luke,Skywalker,Jedi..." Where the ellipses (...) could be additional people. One straightforward approach might be to use fgets() to extract a line from the file, and use preg_match() to extract the table name, records, and fields from that line. However, let's suppose that we have an awful lot of Star Wars characters to track. So many, in fact, that this line ends up being 200,000+ characters/bytes long. In such a case, taking the above approach to extract the database information seems a bit inefficient. You have to first read hundreds of thousands of characters into memory, then read back over those same characters to find regex matches. Is there a way, similar to the Java String next(String pattern) method of the Scanner class constructed using a file, that allows you to match patterns in-line while scanning through the file? The idea is that you don't have to scan through the same text twice (to read it from the file into a string, and then to match patterns) or store the text redundantly in memory (in both the file line string and the matched patterns). Would this even yield a significant increase in performance? It's hard to tell exactly what PHP or Java are doing behind the scenes.

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  • Windows Structured Exception Handling: simple test program will not compile.

    - by Jon
    #include <windows.h> int main() { int* i = (int*)malloc(sizeof(int)); *i = 5; __try { free(i); free(i); } __except { return -1; } return 0; } I am trying to learn more about windows SEH. My first test program is giving me some real trouble. I have looked at the msdn documentation and I am still not really sure what I have wrong. I am getting the following errors when I try to compile this program: error C2059: syntax error : '{' error C2143: syntax error : missing ';' before '{' both on line 15. Thanks.

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  • Alert on gridview edit based on permission

    - by Vicky
    I have a gridview with edit option at the start of the row. Also I maintain a seperate table called Permission where I maintain user permissions. I have three different types of permissions like Admin, Leads, Programmers. These all three will have access to the gridview. Except admin if anyone tries to edit the gridview on clicking the edit option, I need to give an alert like This row has important validation and make sure you make proper changes. When I edit, the action with happen on table called Application. The table has a column called Comments. Also the alert should happen only when they try to edit rows where the Comments column have these values in them. ManLog datas Funding Approved Exported Applications My try so far. public bool IsApplicationUser(string userName) { return CheckUser(userName); } public static bool CheckUser(string userName) { string CS = ConfigurationManager.ConnectionStrings["ConnectionString"].ToString(); DataTable dt = new DataTable(); using (SqlConnection connection = new SqlConnection(CS)) { SqlCommand command = new SqlCommand(); command.Connection = connection; string strquery = "select * from Permissions where AppCode='Nest' and UserID = '" + userName + "'"; SqlCommand cmd = new SqlCommand(strquery, connection); SqlDataAdapter da = new SqlDataAdapter(cmd); da.Fill(dt); } if (dt.Rows.Count >= 1) return true; else return true; } protected void Details_RowCommand(object sender, GridViewCommandEventArgs e) { string currentUser = HttpContext.Current.Request.LogonUserIdentity.Name; string str = ConfigurationManager.ConnectionStrings["ConnectionString"].ToString(); string[] words = currentUser.Split('\\'); currentUser = words[1]; bool appuser = IsApplicationUser(currentUser); if (appuser) { DataSet ds = new DataSet(); using (SqlConnection connection = new SqlConnection(str)) { SqlCommand command = new SqlCommand(); command.Connection = connection; string strquery = "select Role_Cd from User_Role where AppCode='PM' and UserID = '" + currentUser + "'"; SqlCommand cmd = new SqlCommand(strquery, connection); SqlDataAdapter da = new SqlDataAdapter(cmd); da.Fill(ds); } if (e.CommandName.Equals("Edit") && ds.Tables[0].Rows[0]["Role_Cd"].ToString().Trim() != "ADMIN") { int index = Convert.ToInt32(e.CommandArgument); GridView gvCurrentGrid = (GridView)sender; GridViewRow row = gvCurrentGrid.Rows[index]; string strID = ((Label)row.FindControl("lblID")).Text; string strAppName = ((Label)row.FindControl("lblAppName")).Text; Response.Redirect("AddApplication.aspx?ID=" + strID + "&AppName=" + strAppName + "&Edit=True"); } } } Kindly let me know if I need to add something. Thanks for any suggestions.

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  • Object sent -autorelease too many times

    - by mongeta
    I have this code that simple returns Today's date as a string formatted: +(NSString*) getTodayString_YYYY_MM_DD { NSDate * today = [NSDate date]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"yyyy-MM-dd"]; return [[formatter stringFromDate:today] autorelease]; } With instruments I'm not getting a memory leak, but when I Analyze, XCode says: Object sent -autorelease too many times If I understand correctly, I have to release manually the formatter as I'm creating it using 'alloc', but I can't release here because I have to return the value, so I add the autorelease. How I can do it better to improve it ? thanks, r.

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  • Implicit vs explicit getters/setters in AS3, which to use and why?

    - by James
    Since the advent of AS3 I have been working like this: private var loggy:String; public function getLoggy ():String { return loggy; } public function setLoggy ( loggy:String ):void { // checking to make sure loggy's new value is kosher etc... this.loggy = loggy; } and have avoided working like this: private var _loggy:String; public function get loggy ():String { return loggy; } public function set loggy ( loggy:String ):void { // checking to make sure loggy's new value is kosher etc... this.loggy = loggy; } I have avoided using AS3's implicit getters/setters partly so that I can just start typing "get.." and content assist will give me a list of all my getters, and likewise for my setters. I also dislike underscores in my code which turned me off the implicit route. Another reason is that I prefer the feel of this: whateverObject.setLoggy( "loggy's awesome new value!" ); to this: whateverObject.loggy = "loggy's awesome new value!"; I feel that the former better reflects what is actually happening in the code. I am calling functions, not setting values directly. After installing Flash Builder and the great new plugin SourceMate ( which helps to get some of the useful features that FDT is famous into FB ) I realized that when I use SourceMate's "generate getters and setters" feature it automatically sets my code up using the implicit route: private var _loggy:String; public function get loggy ():String { return loggy; } public function set loggy ( loggy:String ):void { // do whatever is needed to check to make sure loggy is an acceptable value this.loggy = loggy; } I figure that these SourceMate people must know what they are doing or they wouldn't be writing workflow enhancement plugins for coding in AS3, so now I am questioning my ways. So my question to you is: Can anyone give me a good reason why I should give up my explicit g/s ways, start using the implicit technique, and embrace those stinky little _underscores for my private vars? Or back me up in my reasons for doing things the way that I do?

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  • Get enum by it's inner field

    - by zeroed
    Hi! Have enum with inner fields, kind of map. Now I need to get enum by it's inner field. Wrote this: package test; /** * Test enum to test enum =) */ public enum TestEnum { ONE(1), TWO(2), THREE(3); private int number; TestEnum(int number) { this.number = number; } public TestEnum findByKey(int i) { TestEnum[] testEnums = TestEnum.values(); for (TestEnum testEnum : testEnums) { if (testEnum.number == i) { return testEnum; } } return null; } } But it's not very efficient to look up through all enums each time I need to find appropriate instance. Is there any other way to do the same?

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  • Are returned locals automatically xvalues

    - by mark
    Following on from a comment I made on this: passing std::vector to constructor and move semantics Is the std::move necessary in the following code, to ensure that the returned value is a xvalue? std::vector<string> buildVector() { std::vector<string> local; // .... build a vector return std::move(local); } It is my understanding that this is required. I have often seen this used when returning a std::unique_ptr from a function, however GManNickG made the following comment: It is my understanding that in a return statement all local variables are automatically xvalues (expiring values) and will be moved, but I'm unsure if that only applies to the returned object itself. So OP should go ahead and put that in there until I'm more confident it shouldn't have to be. :) Can anyone clarify if the std::move is necessary? Is the behaviour compiler dependent?

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  • Why would the assignment operator ever do something different than its matching constructor?

    - by Neil G
    I was reading some boost code, and came across this: inline sparse_vector &assign_temporary(sparse_vector &v) { swap(v); return *this; } template<class AE> inline sparse_vector &operator=(const sparse_vector<AE> &ae) { self_type temporary(ae); return assign_temporary(temporary); } It seems to be mapping all of the constructors to assignment operators. Great. But why did C++ ever opt to make them do different things? All I can think of is scoped_ptr?

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  • errors with gae-sessions and nose

    - by Kekito
    I'm running into a few problems with adding gae-sessions to a relatively mature GAE app. I followed the readme carefully and also looked at the demo. First, just adding the gaesesions directory to my app causes the following error when running tests with nose and nose-gae: Exception ImportError: 'No module named threading' in <bound method local.__del__ of <_threading_local.local object at 0x103e10628>> ignored All the tests run fine so not a big problem but suggests that something isn't right. Next, if I add the following two lines of code: from gaesessions import get_current_session session = get_current_session() I get the following error: Traceback (most recent call last): File "/Users/.../unit_tests.py", line 1421, in testParseFBRequest data = tasks.parse_fb_request(sr) File "/Users/.../tasks.py", line 220, in parse_fb_request session = get_current_session() File "/Users/.../gaesessions/__init__.py", line 36, in get_current_session return _tls.current_session File "/Library/.../python2.7/_threading_local.py", line 193, in __getattribute__ return object.__getattribute__(self, name) AttributeError: 'local' object has no attribute 'current_session' Any suggestions on fixing the above would be greatly appreciated.

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