If I wanted to call a member function inside another member function, how would I do that, if it's possible?
For example, if I have Find(int key) defined already and wanted to call it while i was overloading operator+.
I get the following error in XCode whenever I try to access the member I created 'randomGen' in a separate class in a different header file. I have made sure to include the header file and have tried to access it through an object.
This is the code I enter when trying to access the method from randomiser.h in main.cpp. It is also an overloaded function with doubles and integers:
RandomG randomiser;
randomiser.randomGen(); // 'Call to member function 'randomGen' is ambiguous'
This is the code inside randomiser.h:
#include <string>
#include <iostream>
using std::string;
using std::cout;
using std::endl;
class RandomG {
[Code] ....
This is the error inside xcode: [URL] ....
I have tried seperating the code for the functions in another class (main.cpp) and then running and it seems to works, so I'm not sure why I can't put everything in the .h file and then access it?
I would like it in a seperate file so it doesn't clutter my main. I am writing a game with SDL so that might be confusing and I would like the window to have a random title and other random properties, so it would be easier to use a function.
#include <iostream>
class Hello {
public:
void Test() {
[Code].....
As i know a non-constant member function cant be called inside a constant member function but how the above code has been compiled successfully and giving the expected result .
Say you had:
class Foo{
public:
//...
void funky();
[Code] .....
Would each instance of Foo create a new counter variable, or would it remain the same for all of them, i.e. baz.funky() would always use the same counter variable? What if the class was a template?
I'm writing a small c++ program which will be able to do a few things with a matrix. I have a class called Matrix and a member function in it called getSor() which returns an integer value about the number of lines in the matrix. When I call this getSor() function the program says: error: request for member ‘getSor’ in ‘matrix’, which is of non-class type ‘Matrix*’
- 'matrix' is an existing Matrix object here
- I called the function like this: "cout << matrix.getSor() << endl;"
In my MFC, CMyPorpertyPageDlg is derived from CPropertyPage. How to access its member function from a nonmember function in the same CPP file?.
void Non_Member_Get_PorpertyPage()
{
CMyPorpertyPageDlg* pPageDlg = ....
}
I am modifying a set of static variables inside of the class's member function. The static variables are private. An example of what I'm doing is as below,
utilities.h
-----------
class utilities {
private:
static int num_nodes;
public:
void parse_details(char* );
[Code] ....
I get a compilation error in the function void utilities::parse_details(char* filename)
which says: undefined reference to `utilities::num_nodes'
compiler: g++
How can a member function in my derived class call the same function from its base class?
View 1 Replies View RelatedI've written an Array class to create 1d,2d and 3d array and it works fine for every test : example of the constructor of the array class for 2d case:
Array::Array( int xSize, int ySize ) {
xSize_ = xSize;
ySize_ = ySize;
zSize_ = 1;
vec.resize(xSize*ySize);
}
It works fine , but when i need to use this constructor inside of other constructor, i get the "no matching function error" ,
part of my code:
class StaggeredGrid {
public:
StaggeredGrid ( int xSize1, int ySize1, real dx, real dy ) : p_ (2,2) {}
[Code] .....
I can't get this code to compile (using VS2010 and gcc4.6.1):
Code:
#include <string>
#include <vector>
#include <algorithm>
#include <boost/bind.hpp>
class X {
public:
void foo( const std::vector<std::string>& v ){
[Code] ....
VS2010 presents an error message like "member function already defined or declared" and gcc something like "... function can not be overloaded" (very cryptic error message).
If I change the vector to foo to std::vector<int> and let bar() take an int, it works perfectly fine. And if I use boost
Code:
std::for_each( v.begin(), v.end(), boost::bind( std::mem_fun(&X::bar), this, _1 ) );
The above code compiles as well.
While it is perfectly fine for me to use boost I would nevertheless like to understand what's happening here.
I mount a function (parameter - numeric vector; returns a string). However, this same function is used in several classes. To avoid that I keep duplicating the same code within these classes there is a way to do that as the code below?
std::string func( const vector<int> vec ) {
//processamento
return result;
} class A {
[Code] ....
whether i can define a member function inside a class or not in C++. Is the following code is legal?
#include<iostream> using namespace std;
class adder {
private:
int a;
int b;
int c;
int answer;
public:
[code]....
#include<iostream>
using namespace std;
class Student{
public:
int age;
int rollNo,marks;
string name;
void AddEntry();
[Code] .....
error: non-member function 'void Display(Student*, int)' cannot have cv-qualifier|
why and how can I solve it?
I have an assignment in my OOP c++ class and I had to create a class called date and one of the member functions is a compare function that compares two dates that are taken in. It is suppose to be something like this:
Date d1(12,25,2003);// Dec 25, 2003
Date d2(5,18,2002);// May 18, 2002
d1.Compare(d2);// returns 1 (since d2 comes first)
d2.Compare(d1);// returns -1 (calling object is d2, comes first)
Then if d1 and d2 are equal then it returns 0.
This is what he gave us to start with the function:
int Date::Compare(const Date& d) {
}
I want to take address of a member function in c++. How to do this.
View 2 Replies View RelatedI am trying to use "remove_if" with a predicate function inside a class. The code intends to remove the grid cells which an agent cannot move into (from among all possible cells).
Code:
void classname::function1()
{
vector<MoorePoint> neighbors;
....
[Code]....
That code would work if it was not in a class and the predicate was not a member function. However, now I receive long error messages which I guess refer to incompatibility of remove_if template with the predicate parameter (one error includes : error C2064: term does not evaluate to a function taking 1 arguments).
I am working with a limited compiler (information you may need to know, I don't really know) and I made this function
Code:
void Swap(int &a , int &b); {
Destination temp;
temp = list[a];
list[a] = list[b];
list[b] = temp;
}
In the private part of a class and it is giving me the error "Member function prototypes not supported". How do I fix this and what is a member function prototype exactly?
why can't << operator be overloaded as a member function is it because that is the way c++ is written and you just can't or is there another reason because I'm confused.
View 2 Replies View RelatedI want to have a template function that is a member of a class. Is this possible? This code snippet is how I would think the syntax would go, although it doesn't compile. How would I achieve the same effect?
Code:
class myclass {
public:
int member ;
} ;
template <typename T> void myclass::func( T& arg )
[Code] .....
I need to keep a static variable in a member function of a class that I have many objects of. I've had some trouble with it, and when I read up I found that such variables are static across all instances. Is there any way around this?
View 3 Replies View Relatedi am trying to describe the unusual situation where you declare a class member function with this format:
bool class::function_name(void) const
Specifically where the 'const' follows the parameter list. It is my understanding this is a very useful way of ensuring that whatever code you put in the function definition cannot change any data members of its class.
However I have recently read that this form of declaration should not be used as it leads to less optimized and slower code. Is this correct?
In the below code I'm having trouble calculating the algebraic equation on the line marked with &&&. I attempt to calculate it both within the member function Energy(x) and within find_kin_en(x), but in the latter I find the result equal to zero, which is wrong and disagrees with the correct value calculated in Energy(x). I think the problem might be having multiple nested member functions, i.e. operator() calls Energy(x) which calls find_kin_en().
#include "/u7/tolsma/Numerical_Recipes/nr_c304/code/nr3.h" // these are numerical recipes libraries, not important for the problem below I believe.
#include "/u7/tolsma/Numerical_Recipes/nr_c304/code/mins.h"
#include "/u7/tolsma/Numerical_Recipes/nr_c304/code/mins_ndim.h"
[Code]....
What am I doing wrong with static members and methods here?
compiler errors:
1>test.obj : error LNK2005: "private: static int Test::count" (?count@Test@@0HA) already defined in main.obj
1>c:usersjamesdocumentsvisual studio 2013Projectsstatic_testReleasestatic_test.exe : fatal error LNK1169: one or more multiply defined symbols found
test.h
#ifndef TEST_H_
#define TEST_H_
class Test {
[code]....
I have a class called Point that has functions for getting and setting x, y, and z coords., distance, and midpoint. I need to write a function that prints the class and must use ostream & displayPoint( ostream & ); as the prototype. I did some googling and came up with
std::ostream& Point::displayPoint(std::ostream& out)
{
out << "(" << out.getx() << ", " << out.gety() << ", " << out.getz();
return out;
}
in order to print (x, y, z).
My IDE (Xcode) says "No member named 'getx' in std::__1::basic_ostream<char>"
I don't understand much about ostream reference
So, one can do stuff like this using #defines:
#include <iostream>
#include <array>
#define x arr[0]
#define y arr[1]
#define z arr[2]
class Point {
[code]....
... that is, to be able to reference the same data by "member variables" as by referencing a stl container. But defines are the devil's work - adding in a "#define x arr[0]" is a dangerous statement. I'd really like some nice clean C++ method (C++11 or C++14 are just fine) to do this without defines, but so far I'm drawing a blank. If arr wasn't an STL container, if we just wanted a pointer-based array, I could do it this way:
class Point
{
...
float x __attribute__ ((aligned (sizeof(float))));
float y __attribute__ ((aligned (sizeof(float))));
float z __attribute__ ((aligned (sizeof(float))));
float*const arr = &x;
};
... but you obviously can't do that if arr is an STL container.
The best I've come up with is to make x, y, and z function pointers, but then you can't call them like p.x, you have to call them like *p.x(), it's not very clean and I'd expect some added overhead. One could go even uglier and make x, y, and z be instances of some custom class with overridden operators that reference arr[], but that seems like it'd be just getting ridiculous in terms of overhead (both coding and performance)
template <class T>
void Arreglo<T> :: Registro (ifstream& Entrada) {
Entrada >> Cantidad;
Dealer = new T [Cantidad];
for (int i = 0; i < Cantidad; i++) {
[Code] .....
It says the following error when I comile it:
error: expected type-specifier before 'Detail'
(*(Dealer + i)).Modelo = new Detail[(*(Dealer + i)).AmountModels];
error: expected ';' before 'Detail'