Search Results

Search found 1026 results on 42 pages for 'func'.

Page 22/42 | < Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >

• c# syntax and Linq, IQueryable

  - by hdiver

  Hello. This is a question about the SYNTAX of c# and NOT about how we call/use IQueryable Can someone please explain to me: We have this declaration (System.Linq): public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) and to call the Average double average = fruits.AsQueryable().Average(s => s.Length); I understand how to call the Average and all the similar static method of IQueryable but I don’t understand the syntax of the declaration. public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) What does the <TSource> mean in Average<TSource>( and also the this IQueryable<TSource> source. since only one parameter passes when we call it and the actual lamda expression (s => s.Length); Thanks in advance.

  Read the article

• Is this a good decorator pattern for javascript?

  - by Kucebe

  I need some simple objects that could become more complex later, with many different properties, so i thought to decorator pattern. I made this looking at Crockford's power constructor and object augmentation: //add property to object Object.prototype.addProperty = function(name, func){ for(propertyName in this){ if(propertyName == name){ throw new Error(propertyName + " is already defined"); } } this[name] = func; }; //constructor of base object var BaseConstructor = function(param){ var _privateVar = param; return{ getPrivateVar: function(){ return _privateVar; } }; }; //a simple decorator, adds one private attribute and one privileged method var simpleDecorator = function(obj, param){ var _privateVar = param; var privilegedMethod1 = function(){ return "privateVar of decorator is: " + _privateVar; }; obj.addProperty("privilegedMethod1", privilegedMethod1); return obj; } //a more complex decorator, adds public and private properties var complexDecorator = function(obj, param1, param2){ //private properties var _privateVar = param1; var _privateMethod = function(x){ for(var i=0; i<x; i++){ _privateVar += x; } return _privateVar; }; //public properties var publicVar = "I'm public"; obj.addProperty("publicVar", publicVar); var privilegedMethod2 = function(){ return _privateMethod(param2); }; obj.addProperty("privilegedMethod2", privilegedMethod2); var publicMethod = function(){ var temp = this.privilegedMethod2(); return "do something: " + temp + " - publicVar is: " + this.publicVar; }; obj.addProperty("publicMethod", publicMethod); return obj; } //new basic object var myObj = BaseConstructor("obj1"); //the basic object will be decorated var myObj = simpleDecorator(obj, "aParam"); //the basic object will be decorated with other properties var myObj = complexDecorator(obj, 2, 3); Is this a good way to have Decorator Pattern in javascript? Are there other better ways to do this?

  Read the article

• C++: parsing with simple regular expression or shoud I use sscanf?

  - by Helltone

  I need to parse a string like func1(arg1, arg2); func2(arg3, arg4);. It's not a very complex parsing problem, so I would prefer to avoid resorting to flex/bison or similar utilities. My first approch was to try to use POSIX C regcomp/regexec or Boost implementation of C++ std::regex. I wrote the following regular expression, which does not work (I'll explain why further on). "^" "[ ;\t\n]*" "(" // (1) identifier "[a-zA-Z_][a-zA-Z0-9_]*" ")" "[ \t\n]*" "(" // (2) non-marking "\[" "(" // (3) non-marking "[ \t]*" "(" // (4..n-1) argument "[a-zA-Z0-9_]+" ")" "[ \t\n]*" "," ")*" "[ \t\n]*" "(" // (n) last argument "[a-zA-Z0-9_]+" ")" "]" ")?" "[ \t\n]*" ";" Note that the group 1 captures the identifier and groups 4..n-1 are intended to capture arguments except the last, which is captured by group n. When I apply this regex to, say func(arg1, arg2, arg3) the result I get is an array {func, arg2, arg3}. This is wrong because arg1 is not in it! The problem is that in the standard regex libraries, submarkings only capture the last match. In other words, if you have for instance the regex "((a*|b*))*" applied on "babb", the results of the inner match will be bb and all previous captures will have been forgotten. Another thing that annoys me here is that in case of error there is no way to know which character was not recognized as these functions provide very little information about the state of the parser when the input is rejected. So I don't know if I'm missing something here... In this case should I use sscanf or similar instead? Note that I prefer to use C/C++ standard libraries (and maybe boost).

  Read the article

• Data encapsulation in Swift

  - by zpasternack

  I've read the entire Swift book, and watched all the WWDC videos (all of which I heartily recommend). One thing I'm worried about is data encapsulation. Consider the following (entirely contrived) example: class Stack<T> { var items : T[] = [] func push( newItem: T ) { items.insert( newItem, atIndex: 0 ) } func pop() -> T? { if items.count == 0 { return nil; } return items.removeAtIndex( 0 ); } } This class implements a stack, and implements it using an Array. Problem is, items (like all properties in Swift) is public, so nothing is preventing anyone from directly accessing (or even mutating) it separate from the public API. As a curmudgeonly old C++ guy, this makes me very grumpy. I see people bemoaning the lack of access modifiers, and while I agree they would directly address the issue (and I hear rumors that they might be implemented Soon (TM) ), I wonder what some strategies for data hiding would be in their absence. Have I missed something, or is this simply an omission in the language?

  Read the article

• Strange behavior with Javascript's __defineSetter__

  - by Shea Barton

  I have a large project in which I need to intercept assignments to things like element.src, element.href, element.style, etc. I figured out to do this with defineSetter, but it is behaving very strangely (using Chrome 8.0.552.231) An example: var attribs = ["href", "src", "background", "action", "onblur", "style", "onchange", "onclick", "ondblclick", "onerror", "onfocus", "onkeydown", "onkeypress", "onkeyup", "onmousedown", "onmousemove", "onmouseover", "onmouseup", "onresize", "onselect", "onunload"]; for(a = 0; a < attribs.length; a++) { var attrib_name = attribs[a]; var func = new Function("attrib_value", "this.setAttribute(\"" + attrib_name + "\", attrib_value.toUpperCase());"); HTMLElement.prototype.__defineSetter__(attrib_name, func); } What this code should do is whenever common element attribute in attribs is assigned, it uses setAttribute() to set a uppercased version of that attribute. For some very strange reason, the setter works for only ~1/3 of the assignments. For example with element.src = "test" the new src is "TEST", like it should be however with element.href = "test" the new href is "test", not uppercase then even when I try element.__lookupSetter__("href"), it returns the proper, uppercasing setter the strangest thing is different variables are intercepted properly between Chrome and Firefox help!!

  Read the article

• struct and rand()

  - by teoz

  I have a struct with an array of 100 int (b) and a variable of type int (a) I have a function that checks if the value of "a" is in the array and i have generated the array elements and the variable with random values. but it doesn't work can someone help me fix it? #include <stdio.h> #include <stdlib.h> #include <time.h> typedef struct { int a; int b[100]; } h; int func(h v){ int i; for (i=0;i<100;i++){ if(v.b[i]==v.a) return 1; else return 0; } } int main(int argc, char** argv) { h str; srand(time(0)); int i; for(i=0;0<100;i++){ str.b[i]=(rand() % 10) + 1; } str.a=(rand() % 10) + 1; str.a=1; printf("%d\n",func(str)); return 0; }

  Read the article

• mysql subquery strangely slow

  - by aviv

  I have a query to select from another sub-query select. While the two queries look almost the same the second query (in this sample) runs much slower: SELECT user.id ,user.first_name -- user.* FROM user WHERE user.id IN (SELECT ref_id FROM education WHERE ref_type='user' AND education.institute_id='58' AND education.institute_type='1' ); This query takes 1.2s Explain on this query results: id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY user index first_name 152 141192 Using where; Using index 2 DEPENDENT SUBQUERY education index_subquery ref_type,ref_id,institute_id,institute_type,ref_type_2 ref_id 4 func 1 Using where The second query: SELECT -- user.id -- user.first_name user.* FROM user WHERE user.id IN (SELECT ref_id FROM education WHERE ref_type='user' AND education.institute_id='58' AND education.institute_type='1' ); Takes 45sec to run, with explain: id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY user ALL 141192 Using where 2 DEPENDENT SUBQUERY education index_subquery ref_type,ref_id,institute_id,institute_type,ref_type_2 ref_id 4 func 1 Using where Why is it slower if i query only by index fields? Why both queries scans the full length of the user table? Any ideas how to improve? Thanks.

  Read the article

• Linq - How to collect Anonymous Type as Result for a Function

  - by GibboK

  I use c# 4 asp.net and EF 4. I'm precompiling a query, the result should be a collection of Anonymous Type. At the moment I use this code. public static readonly Func<CmsConnectionStringEntityDataModel, string, dynamic> queryContentsList = CompiledQuery.Compile<CmsConnectionStringEntityDataModel, string, dynamic> ( (ctx, TypeContent) => ctx.CmsContents.Where(c => c.TypeContent == TypeContent & c.IsPublished == true & c.IsDeleted == false) .Select(cnt => new { cnt.Title, cnt.TitleUrl, cnt.ContentId, cnt.TypeContent, cnt.Summary } ) .OrderByDescending(c => c.ContentId)); I suspect the RETURN for the FUNCTION Dynamic does not work properly and I get this error Sequence contains more than one element enter code here. I suppose I need to return for my function a Collection of Anonymous Types... Do you have any idea how to do it? What I'm doing wrong? Please post a sample of code thanks! Update: public class ConcTypeContents { public string Title { get; set; } public string TitleUrl { get; set; } public int ContentId { get; set; } public string TypeContent { get; set; } public string Summary { get; set; } } public static readonly Func<CmsConnectionStringEntityDataModel, string, ConcTypeContents> queryContentsList = CompiledQuery.Compile<CmsConnectionStringEntityDataModel, string, ConcTypeContents>( (ctx, TypeContent) => ctx.CmsContents.Where(c => c.TypeContent == TypeContent & c.IsPublished == true & c.IsDeleted == false) .Select(cnt => new ConcTypeContents { cnt.Title, cnt.TitleUrl, cnt.ContentId, cnt.TypeContent, cnt.Summary }).OrderByDescending(c => c.ContentId));

  Read the article

• linq delegate function checking from objects

  - by Philip

  I am trying to find the list of objects which can be replaced. Class Letter{ int ID; string Name; string AdvCode; int isDeleted; } Class Replacers{ int ID; string MainAdvCode; string ReplacesAdvCode; } example data: Replacers 0 455 400 1 955 400 2 955 455 such that if a Letter has and Advcode of 455 and another has a code of 400 the 400 gets marked for deletion. And then if another Letter has a 955 then the 455 gets marked for deletion and the 400 (which is already marked) is marked for deletion. The problem is with my current code the 400 and 455 is marking itself for deletion?!?!? Public class Main{ List<Letter> Letters; List<Replacers> replaces; //select the ones to replace the replacements aka the little guys //check if the replacements replacer exists if yes mark deleted var filterMethodReplacements = new Func<Letter, bool>(IsAdvInReplacements);//Working var filterMethodReplacers = new Func<Letter, bool>(IsAdvInReplacers);//NOT WORKING???? var resReplacements=letters.Where(filterMethodReplacements);//working foreach (Letter letter in resReplacements) { //select the Replacers aka the ones that contain the little guys var resReplacers = letters.Where(filterMethodReplacers); if (resReplacers != null) letter.isDeleted = 1; } } } private bool IsAdvInReplacements(Letter letter) { return (from a in Replacables where a.ReplaceAdvCode == letter.AdvCode select a).Any(); } private bool IsAdvInReplacers(Letter letter) { //?????????????????????????????? return (from a in Replacables where a.MainAdvCode == letter.AdvCode select a).Any(); } }

  Read the article

• Why can't you return a List from a Compiled Query?

  - by Andrew

  I was speeding up my app by using compiled queries for queries which were getting hit over and over. I tried to implement it like this: Function Select(ByVal fk_id As Integer) As List(SomeEntity) Using db As New DataContext() db.ObjectTrackingEnabled = False Return CompiledSelect(db, fk_id) End Using End Function Shared CompiledSelect As Func(Of DataContext, Integer, List(Of SomeEntity)) = _ CompiledQuery.Compile(Function(db As DataContext, fk_id As Integer) _ (From u In db.SomeEntities _ Where u.SomeLinkedEntity.ID = fk_id _ Select u).ToList()) This did not work and I got this error message: Type : System.ArgumentNullException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 Message : Value cannot be null. Parameter name: value However, when I changed my compiled query to return IQueryable instead of List like so: Function Select(ByVal fk_id As Integer) As List(SomeEntity) Using db As New DataContext() db.ObjectTrackingEnabled = False Return CompiledSelect(db, fk_id).ToList() End Using End Function Shared CompiledSelect As Func(Of DataContext, Integer, IQueryable(Of SomeEntity)) = _ CompiledQuery.Compile(Function(db As DataContext, fk_id As Integer) _ From u In db.SomeEntities _ Where u.SomeLinkedEntity.ID = fk_id _ Select u) It worked fine. Can anyone shed any light as to why this is? BTW, compiled queries rock! They sped up my app by a factor of 2.

  Read the article

• Can't unwrap Optional.None tableviewcell

  - by Mathew Padley

  I've a table view that has a custom table view cell in it. My problem is that when i try and assign a value to a variable in the custom table view cell I get the stated error. Now, I think its because the said variable is not initialised, but its got me completely stumped. This is the custom table cell: import Foundation import UIKit class LocationGeographyTableViewCell: UITableViewCell { //@IBOutlet var Map : MKMapView; @IBOutlet var AddressLine1 : UILabel; @IBOutlet var AddressLine2 : UILabel; @IBOutlet var County : UILabel; @IBOutlet var Postcode : UILabel; @IBOutlet var Telephone : UILabel; var location = VisitedLocation(); func Build(location:VisitedLocation) -> Void { self.location = location; AddressLine1.text = "test"; } } My cell for row at index path is: override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! { var addressCell = tableView.dequeueReusableCellWithIdentifier("ContactDetail") as? LocationGeographyTableViewCell; if !addressCell { addressCell = LocationGeographyTableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "ContactDetail"); } addressCell!.Build(Location); return addressCell; } As I say I'm completely baffled, the Build function calls the correct function in the tableviewcell. Any help will be gratefully appreciated. Ta

  Read the article

• Best way to organize a Go interface

  - by Metropolis

  Hey Everyone, Its been a long time since I have programmed in C++, and if I remember correctly the best way to organize classes was to create your class in the .h file, and then your implementation in your .cpp file. Well I am trying to learn Go now and I was reading over the Go for C++ Programmers article when I came upon interfaces. The article explains that interfaces in Go essentially take the place of classes, and shows how to set them up pretty well. What I am trying to figure out though is how should I organize an interface into files? For instance, should the interface be in one file while the implementation is in another? myInterface.go type myInterface interface { get() int set(i int) } myImplementation.go type myType struct { i int } func (p *myType) set(i int) { p.i = i } func (p *myType) get() int { return p.i } My code here may be wrong since I do not completely know what I am doing yet (and if I am wrong please correct me), but would this be the best way to set this up? Im having a very hard time trying to wrap my head around how to organize code in Go so any help is appreciated! Metropolis

  Read the article

• FireFox: strange behavior on submiting a form

  - by ilnur777

  Can anyone help with this strange form submiting in FireFox? So this form should be submitted after pushing "go to submit" button. There is an onclick event on the button that should submit form through JavaScript. In the form there is another button "test" without any onclick event. Following the script, the form should be submitted only after pushing the "go to submit" button, but it submits even pushing at "test" button. In the Internet Explorer it works well! But this stupid FireFox browser behaves different. Here is example of HTML page: <script> function func(){ document.form1.submit(); } </script> <form name="form1" method="post" action="somewhere.php"> <button>test</button> <input type="button" value="go to submit" onclick="func();"> </form> I have several buttons with <button onclick="...">option 1</button> options. I want to fix strange submiting a form in FireFox. Help please!

  Read the article

• Create lambda action from function expression

  - by Martin Robins

  It is relatively easy to create a lambda function that will return the value of a property from an object, even including deep properties... Func<Category, string> getCategoryName = new Func<Category, string>(c => c.Name); and this can be called as follows... string categoryName = getCategoryName(this.category); But, given only the resulting function above (or the expression originally used to create the function), can anybody provide an easy way to create the opposing action... Action<Category, string> setCategoryName = new Action<Category, string>((c, s) => c.Name = s); ...that will enable the same property value to be set as follows? setCategoryName(this.category, ""); Note that I am looking for a way to create the action programatically from the function or expression - I hope that I have shown that I already know how to create it manually. I am open to answers that work in both .net 3.5 and 4.0. Thanks.

  Read the article

• Does Function pointer make the program slow?

  - by drigoSkalWalker

  Hi guys. I read about function pointers in C And everyone said that will make my program run slow. Is it true? I made a program to check it. And I got the same results on both cases. (mesure the time.) So, is it bad to use fuction pointer? Thanks in advance. To response for some guys. I said 'run slow' for the time that I have compared on a loop. like this. int end = 1000; int i = 0; while (i < end) { fp = func; fp (); } When you execute this, i got the same time if I execute this. while (i < end) { func (); } So I think that function pointer have no difference of time and it don't make a program run slow as many people said.

  Read the article

• Linq - reuse expression on child property

  - by user175528

  Not sure if what I am trying is possible or not, but I'd like to reuse a linq expression on an objects parent property. With the given classes: class Parent { int Id { get; set; } IList<Child> Children { get; set; } string Name { get; set; } } class Child{ int Id { get; set; } Parent Dad { get; set; } string Name { get; set; } } If i then have a helper Expression<Func<Parent,bool> ParentQuery() { Expression<Func<Parent,bool> q = p => p.Name=="foo"; } I then want to use this when querying data out for a child, along the lines of: using(var context=new Entities.Context) { var data=context.Child.Where(c => c.Name=="bar" && c.Dad.Where(ParentQuery)); } I know I can do that on child collections: using(var context=new Entities.Context) { var data=context.Parent.Where(p => p.Name=="foo" && p.Childen.Where(childQuery)); } but cant see any way to do this on a property that isnt a collection. This is just a simplified example, actually the ParentQuery will be more complex and I want to avoid having this repeated in multiple places as rather than just having 2 layers I'll have closer to 5 or 6, but all of them will need to reference the parent query to ensure security.

  Read the article

• Is there a better way to throttle a high throughput job?

  - by ChaosPandion

  I created a simple class that shows what I am trying to do without any noise. Feel free to bash away at my code. That's why I posted it here. public class Throttled : IDisposable { private readonly Action work; private readonly Func<bool> stop; private readonly ManualResetEvent continueProcessing; private readonly Timer throttleTimer; private readonly int throttlePeriod; private readonly int throttleLimit; private int totalProcessed; public Throttled(Action work, Func<bool> stop, int throttlePeriod, int throttleLimit) { this.work = work; this.stop = stop; this.throttlePeriod = throttlePeriod; this.throttleLimit = throttleLimit; continueProcessing = new ManualResetEvent(true); throttleTimer = new Timer(ThrottleUpdate, null, throttlePeriod, throttlePeriod); } public void Dispose() { throttleTimer.Dispose(); ((IDisposable)continueProcessing).Dispose(); } public void Execute() { while (!stop()) { if (Interlocked.Increment(ref totalProcessed) > throttleLimit) { lock (continueProcessing) { continueProcessing.Reset(); } if (!continueProcessing.WaitOne(throttlePeriod)) { throw new TimeoutException(); } } work(); } } private void ThrottleUpdate(object state) { Interlocked.Exchange(ref totalProcessed, 0); lock (continueProcessing) { continueProcessing.Set(); } } }

  Read the article

• GridView ObjectDataSource LINQ Paging and Sorting using multiple table query.

  - by user367426

  I am trying to create a pageing and sorting object data source that before execution returns all results, then sorts on these results before filtering and then using the take and skip methods with the aim of retrieving just a subset of results from the database (saving on database traffic). this is based on the following article: http://www.singingeels.com/Blogs/Nullable/2008/03/26/Dynamic_LINQ_OrderBy_using_String_Names.aspx Now I have managed to get this working even creating lambda expressions to reflect the sort expression returned from the grid even finding out the data type to sort for DateTime and Decimal. public static string GetReturnType<TInput>(string value) { var param = Expression.Parameter(typeof(TInput), "o"); Expression a = Expression.Property(param, "DisplayPriceType"); Expression b = Expression.Property(a, "Name"); Expression converted = Expression.Convert(Expression.Property(param, value), typeof(object)); Expression<Func<TInput, object>> mySortExpression = Expression.Lambda<Func<TInput, object>>(converted, param); UnaryExpression member = (UnaryExpression)mySortExpression.Body; return member.Operand.Type.FullName; } Now the problem I have is that many of the Queries return joined tables and I would like to sort on fields from the other tables. So when executing a query you can create a function that will assign the properties from other tables to properties created in the partial class. public static Account InitAccount(Account account) { account.CurrencyName = account.Currency.Name; account.PriceTypeName = account.DisplayPriceType.Name; return account; } So my question is, is there a way to assign the value from the joined table to the property of the current table partial class? i have tried using. from a in dc.Accounts where a.CompanyID == companyID && a.Archived == null select new { PriceTypeName = a.DisplayPriceType.Name}) but this seems to mess up my SortExpression. Any help on this would be much appreciated, I do understand that this is complex stuff.

  Read the article

• How to setup and teardown temporary django db for unit testing?

  - by blokeley

  I would like to have a python module containing some unit tests that I can pass to hg bisect --command. The unit tests are testing some functionality of a django app, but I don't think I can use hg bisect --command manage.py test mytestapp because mytestapp would have to be enabled in settings.py, and the edits to settings.py would be clobbered when hg bisect updates the working directory. Therefore, I would like to know if something like the following is the best way to go: import functools, os, sys, unittest sys.path.append(path_to_myproject) os.environ['DJANGO_SETTINGS_MODULE'] = 'myapp.settings' def with_test_db(func): """Decorator to setup and teardown test db.""" @functools.wraps def wrapper(*args, **kwargs): try: # Set up temporary django db func(*args, **kwargs) finally: # Tear down temporary django db class TestCase(unittest.TestCase): @with_test_db def test(self): # Do some tests using the temporary django db self.fail('Mark this revision as bad.') if '__main__' == __name__: unittest.main() I should be most grateful if you could advise either: If there is a simpler way, perhaps subclassing django.test.TestCase but not editing settings.py or, if not; What the lines above that say "Set up temporary django db" and "Tear down temporary django db" should be?

  Read the article

• Need help profiling .NET caching extension method.

  - by rockinthesixstring

  I've got the following extension Public Module CacheExtensions Sub New() End Sub Private sync As New Object() Public Const DefaultCacheExpiration As Integer = 1200 ''# 20 minutes <Extension()> Public Function GetOrStore(Of T)(ByVal cache As Cache, ByVal key As String, ByVal generator As Func(Of T)) As T Return cache.GetOrStore(key, If(generator IsNot Nothing, generator(), Nothing), DefaultCacheExpiration) End Function <Extension()> Public Function GetOrStore(Of T)(ByVal cache As Cache, ByVal key As String, ByVal generator As Func(Of T), ByVal expireInSeconds As Double) As T Return cache.GetOrStore(key, If(generator IsNot Nothing, generator(), Nothing), expireInSeconds) End Function <Extension()> Public Function GetOrStore(Of T)(ByVal cache As Cache, ByVal key As String, ByVal obj As T) As T Return cache.GetOrStore(key, obj, DefaultCacheExpiration) End Function <Extension()> Public Function GetOrStore(Of T)(ByVal cache As Cache, ByVal key As String, ByVal obj As T, ByVal expireInSeconds As Double) As T Dim result = cache(key) If result Is Nothing Then SyncLock sync If result Is Nothing Then result = If(obj IsNot Nothing, obj, Nothing) cache.Insert(key, result, Nothing, DateTime.Now.AddSeconds(expireInSeconds), cache.NoSlidingExpiration) End If End SyncLock End If Return DirectCast(result, T) End Function End Module From here, I'm using the extension is a TagService to get a list of tags Public Function GetTagNames() As List(Of String) Implements Domain.ITagService.GetTags ''# We're not using a dynamic Cache key because the list of TagNames ''# will persist across all users in all regions. Return HttpRuntime.Cache.GetOrStore(Of List(Of String))("TagNamesOnly", Function() _TagRepository.Read().Select(Function(t) t.Name).OrderBy(Function(t) t).ToList()) End Function All of this is pretty much straight forward except when I put a breakpoint on _TagRepository.Read(). The problem is that it is getting called on every request, when I thought that it is only to be called when Result Is Nothing Am I missing something here?

  Read the article

• Determine if a Range contains a value

  - by Brad Dwyer

  I'm trying to figure out a way to determine if a value falls within a Range in Swift. Basically what I'm trying to do is adapt one of the examples switch statement examples to do something like this: let point = (1, -1) switch point { case let (x, y) where (0..5).contains(x): println("(\(x), \(y)) has an x val between 0 and 5.") default: println("This point has an x val outside 0 and 5.") } As far as I can tell, there isn't any built in way to do what my imaginary .contains method above does. So I tried to extend the Range class. I ended up running into issues with generics though. I can't extend Range<Int> so I had to try to extend Range itself. The closest I got was this but it doesn't work since >= and <= aren't defined for ForwardIndex extension Range { func contains(val:ForwardIndex) -> Bool { return val >= self.startIndex && val <= self.endIndex } } How would I go about adding a .contains method to Range? Or is there a better way to determine whether a value falls within a range? Edit2: This seems to work to extend Range extension Range { func contains(val:T) -> Bool { for x in self { if(x == val) { return true } } return false } } var a = 0..5 a.contains(3) // true a.contains(6) // false a.contains(-5) // false I am very interested in the ~= operator mentioned below though; looking into that now.

  Read the article

• HELP Retrieving the url parameter from a JSON store from a EXTJS ComboBox

  - by Newbie

  I am having a problem retrieving the parameters from the url section of a json store for a combobox in EXTJS from my code behind page in c#. The following is the code in the store: var ColorStore = new Ext.data.JsonStore( { autoLoad: true, url: '/proxies/ReturnJSON.aspx?view=rm_colour_view', root: 'Rows', fields: ['company', 'raw_mat_col_code', 'raw_mat_col_desc'] }); And the following code is in my code behind page: protected void Page_Load(object sender, EventArgs e) { string jSonString = ""; connectionClass.connClass func = new connectionClass.connClass(); DataTable dt = func.getDataTable("sELECT * from rm_colour_view"); //Response.Write(Request.QueryString["view"]); string w = Request.Params.Get("url"); string z = Request.Params.Get("view"); string x = Request.Params.Get("view="); string c = Request.Params.Get("?view"); string s = Request.QueryString.Get("view"); string d = Request.Params["?view="]; string f = Request.Form["ColorStore"]; jSonString = Serialize(dt); Response.Write(jSonString); } The string w has gives the following output: /proxies/ReturnJSON.aspx but all the others strings return null... How can rm_colour_view from the datastore then be retrived??? Any help would be appreciated! Thanks

  Read the article

• In this example where is the C++ assignment operator used rather than the copy constructor ?

  - by Bill Forster

  As part of an ongoing process of trying to upgrade my C++ skills, I am trying to break some old habits. My old school C programmer inclination is to write this; void func( Widget &ref ) { Widget w; // default constructor int i; for( i=0; i<10; i++ ) { w = ref; // assignment operator // do stuff that modifies w } } This works well. But I think the following is closer to best practice; void func( Widget &ref ) { for( int i=0; i<10; i++ ) { Widget w = ref; // ?? // do stuff that modifies w } } With my Widget class at least, this works fine. But I don't fully understand why. I have two theories; 1) The copy constructor runs 10 times. 2) The copy constructor runs once then the assignment operator runs 9 times. Both of these trouble me a little. 2) in particular seems artificial and wrong. Is there a third possibility that I am missing ?

  Read the article

• Trouble with go tour crawler exercise

  - by David Mason

  I'm going through the go tour and I feel like I have a pretty good understanding of the language except for concurrency. On slide 71 there is an exercise that asks the reader to parallelize a web crawler (and to make it not cover repeats but I haven't gotten there yet.) Here is what I have so far: func Crawl(url string, depth int, fetcher Fetcher, ch chan string) { if depth <= 0 { return } body, urls, err := fetcher.Fetch(url) if err != nil { ch <- fmt.Sprintln(err) return } ch <- fmt.Sprintf("found: %s %q\n", url, body) for _, u := range urls { go Crawl(u, depth-1, fetcher, ch) } } func main() { ch := make(chan string, 100) go Crawl("http://golang.org/", 4, fetcher, ch) for i := range ch { fmt.Println(i) } } The issue I have is where to put the close(ch) call. If I put a defer close(ch) somewhere in the Crawl method, then I end up writing to a closed channel in one of the spawned goroutines, since the method will finish execution before the spawned goroutines do. If I omit the call to close(ch), as is shown in my example code, the program deadlocks after all the goroutines finish executing but the main thread is still waiting on the channel in the for loop since the channel was never closed.

  Read the article

• C# Linq Select Problem in Method Chain.

  - by Gnought

  Note that the _src inherit IQueryable<U> and V inherit new(); I wrote the following statement, there is no syntax error. IQueryable<V> a = from s in _src where (s.Right - 1 == s.Left) select new V(); But if i re-wrote it as follows, the Visual Studio editor complains an error in the "Select" IQueryable<V> d = _src.Where(s => s.Right - 1 == s.Left).Select(s=> new V()); The Error is: The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly. Candidates are: System.Collections.Generic.IEnumerable<V> Select<U,V>(this System.Collections.Generic.IEnumerable<U>, System.Func<U,V>) (in class Enumerable) System.Linq.IQueryable<V> Select<U,V>(this System.Linq.IQueryable<U>, System.Linq.Expressions.Expression<System.Func<U,V>>) (in class Queryable) Could anyone explain this phenomenon, and what the solution is to fix the error?

  Read the article

< Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >