C++ :: Extended Initializer Lists Flag On Class Constructor
Apr 8, 2013
I just got this warning from codeblocks:
Code: extended initializer lists only available with -std=c++11 or -std=gnu++11 that I belive is due to having initialized a class array in the constructor somewhat like this:
Code: class xpto {
public;
xpto():num{25,25}{}
int num[2];
};
Since the code I'm developing is not meant to be compiled only by me and I want to ensure there are no incompatibilities with other machines I would like to kow whats the best way to initialize the array that is not c++11 dependent.
Is there no way to do it directly on the constructor "pre-instructions" (don't know the correct designation for the initialization section)? or do I have to put the instructions on the constructor body.
Constructor of the Base Class Person::Person(char* n="", char* nat="U.S.A", int s=1) { name = n; nationality = nat; sex = s; }
Constructor of the Derived Class (inherited from the base class)
Student(char* n, int s=0, char* i=""): Person(n, s)
Why the initialized list of the base class constructor doesn't match the initialized list of the derived class constructor? I know this book is a little bit old, I'm not sure if this wrong in VC++ 2010?
Let's say I have a Car object , and it contains inner Engine object.
Code: struct Car{ Engine mEngine; };
In order to initialize the engine object NOT by the default constructor (if it has any) , we use initialization semantics:
Code: Car::Car: mEngin(arg1,arg2,...) { other stuff here }
Now it gets tricky: Let's say a Car objects has 10 inner objects, each object has about 5 variables in it . Car is a base class for , e.g. , Toyota class. you don't want the Car class to have a constructor with 50 arguments. Can the inner objects of Car be initialized from the base class , e.g. Toyota?
Code: class Toyota: Car(...), mEngine(...), mGear(..) { ... };
The other options are: 1) like said , create a Car constructor which gets 50 arguments, then initialize Car as whole from Toyota - the code becomes less readable and less intuitive 2) Car constructor which get built-objects as arguments and initialize the inner objects with copy constructor . the code gets more readable but then you create many excess objects .
The idea, was to show that when you compile with the /GF flag set, string pooling is enabled, and the const char*'s which point to string literals would point to the same, read-only memory location. However, the addresses are still different.
Obviously, I'm compiling with /GF set. I'm using VC++2008 IDE if it makes a difference.
I have downloaded an extended tool set for WPF as directed in the tutorial here: [URL]However, when I try to drag anything from the toolset(say a decimalupdown) to the WPF code, I get the errors
Error1DecimalUpDown is not supported in a Windows Presentation Foundation (WPF) project.D:ProgrammingNumberTracking2NumberTracking2Mainwindow.xaml129NumberTracking2
[Code] .....
I'm guessing that there may be some additional things that I have to do to get this to work
Looking for extended unsigned integer class, that has custom lenght?
The reason i am asking is because i need an extremely large integer number, in fact one that has no theoretical limit(or at least an extremely large one).
# include <iostream> # include <cstring> #include <iomanip> #include <cmath> using namespace std; class Course // Creating the class Course
[Code] ....
Errors: Warning1warning C4996: 'strncpy': This function or variable may be unsafe. Consider using strncpy_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
[Code] .....
I have to create an Array of type Course and then fill its member dats using various member functions. Those errors are caused by some Constructor defect, which I dont really know what it is.
It looks useful to implement strategy pattern because it makes a fully separate code block. So I can add a function to the map simply by compiling a source file. It's very simple. I don't need to edit another file.
But when I use it for my existing project, It makes some linking and runtime errors.(vs 2012). I can't recognize exactly why because it is a huge project. Anyway, I have a question that - Is this a safe use of class constructor?
I know that there is no fixed order of running, but in this case I think it doesn't matter. because they are independent. But it is not a common pattern, so I can't decide to use it.
The problem I have is with the Size constructor and the abstract class LevelObject which size is a member of.
The compiler error I get is:
C:Program Files (x86)ProgrammingProjectsUniversityprg_interactivesnakey_takeysrc..inc..incPlayer.hpp|17|warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11 [enabled by default]| C:Program Files (x86)ProgrammingProjectsUniversityprg_interactivesnakey_takeysrc..inc..inc..incPlayer.hpp|17|warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11 [enabled by default]|
[Code] .....
However I do invoke the copy constructor when I pass a variable of type size to the constructor in this line:
size_ = Size(s);
But the problem is that its complaining that the abstract class LevelObject doesn't invoke the constructor, which it shouldn't.
When the below is done, does it call the constroctor only, and if yes, constructors do not have return types so how does it work? is there anything behind the scene?
wxAddHandler(new wxPNG_HANDLER); and sf::RenderWindow(sf::VideoMode(...),...);
Can I determine if a templated class has a particular constructor, in my case using a string within function to which T is used?
Code:
template<class T> void MakeObject(std::vector<T>& dataVector) { std::string str "con string,Joe,24"; // catch if T has string constructor T someObject(str); // T someObject should have constructor from string dataVector.push_back(someObject); }
I am unable to understand how a move constructor works in this example of code. If someone could break down the process of what is taking place and explain to me on why to use a move constructor.
Code: class MyString { MyString(MyString&& MoveSource) { if( MoveSource.Buffer != NULL ) { Buffer = MoveSource.Buffer; // take ownership i.e. 'move' MoveSource.Buffer = NULL; // set the move source to NULL i.e. free it } } };
Example from "SamsTeachYourself: C++ in One Hour a Day"
