Search Results

Search found 7666 results on 307 pages for 'pointer to member'.

Page 148/307 | < Previous Page | 144 145 146 147 148 149 150 151 152 153 154 155  | Next Page >

  • F# compilation error: Unexpected type application

    - by Jim Burger
    In F#, given the following class: type Foo() = member this.Bar<'t> (arg0:string) = ignore() Why does the following compile: let f = new Foo() f.Bar<Int32> "string" While the following won't compile: let f = new Foo() "string" |> f.Bar<Int32> //The compiler returns the error: "Unexpected type application"

    Read the article

  • Does binding temporary to a reference require a copy constructor in C++?

    - by vitaut
    Consider the following code: class A { A(const A&); public: A() {} }; int main() { const A &a = A(); } This code compiles fine with GCC, but fails to compile with Visual C++ with the following error: test.cc(8) : error C2248: 'A::A' : cannot access private member declared in class 'A' test.cc(2) : see declaration of 'A::A' test.cc(1) : see declaration of 'A' So is it necessary to have a copy constructor accessible when binding a temporary to a reference?

    Read the article

  • STL map - insert or update

    - by CodeJunkie
    I have a map of objects and I want to update the object mapped to a key, or create a new object and insert into the map. The update is done by a different function that takes a pointer to the object (void update(MyClass *obj)) What is the best way to "insert or update" an element in a map?

    Read the article

  • Convert NSString to string

    - by coure06
    NSDate *now = [NSDate date]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"yyyy"]; NSString *stringFromDate = [formatter stringFromDate:now]; CGContextShowTextAtPoint(context, 50, 50, stringFromDate, 5); I am not getting the exact date? also getting warning while compiling warning: passing argument 4 of 'CGContextShowTextAtPoint' from incompatible pointer type

    Read the article

  • What is the point of function pointers?

    - by gramm
    Hi, I have trouble seing the utility of the function pointers. I guess it may be useful in some cases (they exist, after all), but I can't think of a case where it's better or unavoidable to use a function pointer. Could you give some example of good use of function pointers (in C or C++)? Many thanks :)

    Read the article

  • backbonejs remove anomaly concept

    - by user1537158
    I was building a small app for adding and deleting li from ul using Backbonejs.One of the SO members cymen helped me code it, using that i tailored the code a little.currently if i add one element and delete , it works , but the second time i add an element (to ul) and go to delete it , i get Uncaught TypeError: Cannot call method 'remove' of undefined Pasting my code here , HTML : <input type="text" id="name"> <button id="add">Add</button> <ul id="mylist"></ul> JS: $(function(){ var myCollection = Backbone.Collection.extend(); var myView = Backbone.View.extend({ el:$('body'), tagName:'li', initialize : function(e){ this.collection.bind("add",this.render,this); this.collection.bind("remove",this.render,this); }, events:{ 'click #add' : 'addfoo' }, addfoo : function(){ var myname= $('#name').val(); $('#name').val(''); this.collection.add({name:myname}); }, render : function(){ $('#mylist').empty(); this.collection.each(function(model){ console.log("myView"); var remove = new myRemoveView({model:model}); remove.render(); }); } }); var myRemoveView = Backbone.View.extend({ el:$('body'), events:{ 'click .button':'removeFoo' }, removeFoo : function(){ console.log("here"); this.model.collection.remove(this.model); }, render : function(){ console.log("second view"); $('#mylist').append('<li>'+this.model.get('name') + "<button class='button'>"+"delete"+"</button></li>"); return; } }); var view = new myView({collection: new myCollection()}); }); Two things i did not understand : i) in the removeFoo function , we write this.model.collection.remove(this.model) shouldnt this have been this.collection.model.remove , something of that sort ? ii) i add a li to ul , then i delete it , when i add another li (appending to ul works perfect) but this time when i go to delete it throws me the above error : Uncaught TypeError :cannot call method 'remove' of undefined can you please help me figure out these 2 doubts in my code , btw SO member cymen's code works like a charm only my tailored code (above) is giving me errors. SO member cymen's code : JS Fiddle for his code Thank you

    Read the article

  • gcc -Wshadow is too strict?

    - by idimba
    In the following example: class A { int len(); void setLen(int len) { len_ = len; } // warning at this line int len_; }; gcc with -Wshadow issue a warning: main.cpp:4: warning: declaration of `len' shadows a member of `this' function len and integer len are of different type. Why the warning?

    Read the article

  • Inlining an array of non-default constructible objects in a C++ class

    - by porgarmingduod
    C++ doesn't allow a class containing an array of items that are not default constructible: class Gordian { public: int member; Gordian(int must_have_variable) : member(must_have_variable) {} }; class Knot { Gordian* pointer_array[8]; // Sure, this works. Gordian inlined_array[8]; // Won't compile. Can't be initialized. }; As even beginner C++ users know, the language guarantees that all members are initialized when constructing a class. And it doesn't trust the user to initialize everything in the constructor - one has to provide valid arguments to the constructors of all members before the body of the constructor even starts. Generally, that's a great idea as far as I'm concerned, but I've come across a situation where it would be a lot easier if I could actually have an array of non-default constructible objects. The obvious solution: Have an array of pointers to the objects. This is not optimal in my case, as I am using shared memory. It would force me to do extra allocation from an already contended resource (that is, the shared memory). The entire reason I want to have the array inlined in the object is to reduce the number of allocations. This is a situation where I would be willing to use a hack, even an ugly one, provided it works. One possible hack I am thinking about would be: class Knot { public: struct dummy { char padding[sizeof(Gordian)]; }; dummy inlined_array[8]; Gordian* get(int index) { return reinterpret_cast<Gordian*>(&inlined_array[index]); } Knot() { for (int x = 0; x != 8; x++) { new (get(x)) Gordian(x*x); } } }; Sure, it compiles, but I'm not exactly an experienced C++ programmer. That is, I couldn't possibly trust my hacks less. So, the questions: 1) Does the hack I came up with seem workable? What are the issues? (I'm mainly concerned with C++0x on newer versions of GCC). 2) Is there a better way to inline an array of non-default constructible objects in a class?

    Read the article

  • How should I lay-out my PHP login class?

    - by ThinkingInBits
    So, there is going to be one login form; however 1 of 3 types of members will be signing in member_type_a, member_type_b, member_type_c all of whom have some of the same properties, and some whom may have specific methods and/or properties to them. I want the class to be saved to a session variable for use with member area pages. Any suggestions on applicable design patterns?

    Read the article

  • Can get Sum() working in Northwind example

    - by Vince
    Hi, The following code is generating a runtime error and I have no idea why. from o in Orders group o by o.Employee into employeeOrders select new { employeeOrders.Key.EmployeeID, employeeOrders.Key.FirstName, Orders = from eord in employeeOrders orderby eord.OrderID select new { eord.OrderID, eord.OrderDate, OrderTotal=eord.OrderDetails.Sum (od => od.UnitPrice) } } The error is Member access 'System.Decimal UnitPrice' of 'LINQPad.User.OrderDetails' not legal on type 'LINQPad.User.Orders Thanks in advance

    Read the article

  • Return reference from class to this.

    - by Thomas
    Hi, I have the following member of class foo. foo &foo::bar() { return this; } But I am getting compiler errors. What stupid thing am I doing wrong? Compiler error (gcc): error: invalid initialization of non-const reference of type 'foo&' from a temporary of type 'foo* const'

    Read the article

  • Determining the word width in C

    - by das_weezul
    Hi! I'm learning C right now and so I'm fiddling about with pointers. Is there a way to determine the word width of the CPU in C because I'm writing a small program which prints it's own stack (Because I'm curious how it is structured), so that information would come in handy. Right now I'm using an int pointer, as an integer is 4 Bytes wide and I'm using a 32-bit Intel Atom CPU. Thanks in advance, C gurus ;o)

    Read the article

  • Passing data to overridden base method in C#

    - by UpTheCreek
    Bit of a dumb question, but I'm wondering what the accepted way of passing data from back to an overridden base method is in c#. e.g. I guess I could do: class A { int x; public virtual void DoStuff() { Console.WriteLine(x); } } class B : A { public override void DoStuff() { x = 1; base.DoStuff(); } } But is there a better method that for example doesn't require the use of a member variable?

    Read the article

  • Linux signals with extra information parameter

    - by Tester
    I was to have some extra information in the callback to sa_sigaction handler, it does not seems possible. So I was wondering if you could suggest me alternatives. Basic requirements: Function A raises an signal/event with a pointer to a struct Handler function tackles the event. The handler function would only be called on an event and a loop to wait for the event, as in select() , is undesirable. TIA

    Read the article

  • Auto comment all public members in a file

    - by ooo
    I have turned on warnings as errors and now i need to XML comment all of my public methods. just to get my program compiling, i just want to put placeholders for now. Is there anyway to automatically add XML comments to all of the public members in a class or a file. I see ghost doc which gives you good autogenerated XML comments but it still looks like it only does one member at a time.

    Read the article

  • Is this technically thread safe despite being mutable?

    - by Finbarr
    Yes, the private member variable bar should be final right? But actually, in this instance, it is an atomic operation to simply read the value of an int. So is this technically thread safe? class foo { private int bar; public foo(int bar) { this.bar = bar; } public int getBar() { return bar; } } // assume infinite number of threads repeatedly calling getBar on the same instance of foo.

    Read the article

  • LInux C++: how do profile time wasted due to cache misses?

    - by anon
    I know that I can use gprof to benchmark my code. However, I have this problem -- I have a smart pointer that has an extra level of indirection (think of it as a proxy object). As a result, I have this extra layer that effects pretty much all functions, and screws with caching. Is there a way to measure the time my CPU wastes due to cache misses? Thanks!

    Read the article

  • Generate set/get methods for a c++ class

    - by Narek
    Is there any tool that generates set and get methods for a class. Just I create classes very frequently and would like to have a tool which for each class-member wil generate following functions: Member_Type getMemberName() const; void setMemberName(const Member_Type & val);

    Read the article

  • What do people find difficult about C pointers?

    - by Paul
    From the number of questions posted here, it's clear that people have some pretty fundemental issues when getting their heads around pointers and pointer arithmetic. I'm curious to know why. They've never really caused me major problems (although I first learned about them back in the Neolithic). In order to write better answers to these questions, I'd like to know what people find difficult. So, if you're struggling with pointers, or you recently were but suddenly "got it", what were the aspects of pointers that caused you problems?

    Read the article

< Previous Page | 144 145 146 147 148 149 150 151 152 153 154 155  | Next Page >