Is there a difference between having static and dynamic cast in this scenario? The output is the same.
Code:
Base* pb = new Derived();
if(Derived* pd2 = static_cast<Derived*>(pb)) // true {
pd2->get_price(); // calls Base::get_price()
pd2->get_rate(); // calls Derived::get_rate()
[Code] ....
what is main difference between the static array and a dynamic array....also i am confused with dynamic array and dynamic allocated array?
View 3 Replies View RelatedIs it possible to handle situations where static cast fails. I have a sample code written belo:
typedef struct test {
int a;
int b;
} tester;
void setevent(void *in) {
tester *recv = static_cast<tester*>(in);
[Code] ....
In above code when setevent is called with the tester object, there is no issue, but if we pass random value it leads to seg fault. This is because static_cast is not type_safe, but can it be handled in any other way?
Here is the code,
Code:
class B {
};
class D1:public B {
};
class D2:public D1 {
};
int main() {
B& b = dynamic_cast<B&>(*(new D2));
return 0;
}
D2 is actually grandchild of B, so D2 object reference can still be converted to B reference without any exception. Is it legal?
I have the next program: if I comment the assignation mNum=num; or mCh=ch the segmentation fault don't exist.
#include <vector>
class Base{
public:
[Code]....
Code: Obj<TCHAR>* obj = dynamic_cast<Obj<TCHAR>* >(I->objects[0]);
Which is resulting in this error
Code: A dynamic cast is present, but the correct RTTI option is not specified.
Here is the code,
Code:
class A {
};
A& CreateObject() {
static A a;
return a;
} static A aa;
int main() {
return 0;
}
So is there any difference between a defined in CreateObject and aa?
I want to know
prog1.c
#include<stdio.c>
static int c=6;
int main() {
/*code*/
}
prog2.c
#include<stdio.h>
int main(){
static int c=10;
}
what would be the difference between these two program in the fuctioning of static keyword ?
there is a performance difference (e.g access time, speed, ...) between allocating static memory vs dynamic memory?
For example, if am reading data from a file, and storing them inside a huge buffer, what would be the differences between storing these data inside a static buffer vs a dynamic one?
consider the code bellow
#include<iostream>
#include<ctime>
#include<boost/progress.hpp>
using namespace std;
class parent {
public:
virtual void dynamic_display(){
[Code] ....
I am getting the following as output
Calculating....Static Function is called1times
The number of processor clicks is0time is0
Calculating....Dynamic function is called1times
The number of processor clicks is0time is0
Static Function is called2times
Dynamic function is called2times
Static Function is called3times
Dynamic function is called3times
I am actually trying to calculate the time to execute a statically binding method and a dynamically binded one.consider only the first four lines in my output. Why am i not getting the actual result.
How I can implement it.
Tickable.h
#include <list>
#ifdef TICKABLE_EXPORTS //Automatically defined by MSVS
#define DLL __declspec(dllexport)
#else
#define DLL __declspec(dllimport)
#pragma comment(lib, "Tickable.lib")
#endif
class DLL Tickable{
[Code] ....
error LNK2001:
unresolved external symbol "private: static class std::list<class Tickable*,SKIPPED BITS> Tickable::subs" HUGE_SYMBOL_LIST
PATHTickable.obj
I know with such a tiny and insignificant class the dll export seems pointless but this class is actually intended to be a .lib ONLY. But it is derived from by .dll style classes, and through inheritance this error is the exact same as what appears in the derived class, I just imagine that the cut down version would be easier to work with.
Is it possible to hold either a static variable in a dll which is of a dynamic type, OR would it be possible to reference an external variable which is static throughout the instances and this variable can be chucked away in a namespace of mine somewhere?
I suppose my only other option (if this is possible) would be to define a maximum instance number and create a standard array of pointers but this could both waste so much memory when not in use and cause problems if I need more memory.
difference between const and static const, more effectively. I know the basic concept of const and static but I need clear explanation of declaring "const" and "static const"
Ex:
const int a;
static const int a;
i need a function that will work for both dynamic and static implementations of a function to get the transverse of a matrix. so far, i have this
Code:
matrix transpose(matrix m)
{
int row, col;
row = m.com_dim;
col= m.row_dim;
}
[code]....
this works well with my static implementation, but when i try it in dynamic it gives me errors. the function has to be the same for both dynamic and static implementation
But it can the other way around
Code:
static_Array= dynamic_Array;
dynamic_Array = static_Array;
The second statement works and i'm able to print out both arrays with equal values but with the first
[code] static_Array = dynamic_Array;I get incompatible types in assignment of 'int*' to 'int [7]' is the error I get [/code]
From my book:
"A static function might have this prototype:
static void Afunction(int n);
A static function can be called in relation to a particular object by a statement such as the following:
aBox.Afunction(10);
The function has no access to the non-static members of aBox. The same function could also be called without reference to an object. In this case, the statement would be:
CBox::Afunction(10);
where CBox is the class name. Using the class name and the scope resolution operator tells the compiler to which class Afunction() belongs."
Why exactly cant Afunction access non-static members?
What are the workarounds for accessing the non-static member variables of some class(Say A) inside static member functions of another class(Say B)? I am coding in c++. Class A is derived with public properties of class B. Any pointers?
View 7 Replies View RelatedHave following code:
class Program
{
static void Main(string[] args)
{
[Code]....
My question according to what i just wrote:
1. Is that mean that Do() is only available for use by Dog itself because Dog is 'oryginal' Dog, and if i create new dogs - instances of oryginal Dog (dog1, dog2 ...) they cant access because Do is only available fo 'oryginal' one? Is that correct thinking?
2. If i would want to have something common (e.g value) for all dogs is that good way to create static field/method for Dog instead of non-static once then all instances of Dog would access Dog static member to get/change it? Just stupid example: static method GetAmountOfLegs() which return 4 Then all instances can take/call that value from Dog. Is that correct thinking?
I'm writing a program in which I have to use a matrix to represent a file in code. because it's a file, the size of the matrix is undefined, and therefore the matrix has to be dynamic. I found out that my compiler doesn't like dynamic multidimensional arrays, so I was thinking of this matrix as a dynamic (monodimensional) array of other dynamic (monodimensional) arrays. My program (and thus this example) uses unsigned chars.
unsigned char variable=something;
unsigned char**matrix=new unsigned char*[lenghtOfMainArray];
for(int rowNumber=0;rowNumber<lenghtOfArray;rowNumber++)
{
[Code].....
i'm implementing a playerclass for a game.. in the game there are multiple player types, weapons ect.. i just wanted to turn my players weapons into a dynamically allocated c_str. once i added my: Destructor, Copy Constructor and Overloaded Assignment Operator. My initial values became corrupted and i cannot fix them.
Player2.cpp
#include <string.h>
#include <iostream>
#include <cstdlib>
#include <iostream>
#include "player2.h"
#include "dice.h"
#include "gamespace.h"
[code]....
Is it possible to get the string representation of an int. So I mean if i have: 5, I want to get '5'.
I was searching in the internet and I found this solution:
Code:
int number = 5;
char c = number + '0'; which works fine for small numbers, but if I do:
Code: int i;
char c;
for(i =0; i < 10000; i++) {
c = i + '0';
printf("%c
", c);
}
At some point some strange sings like %&/)/)$%&) are appearing, But i really need this huge numbers as well .. Is there any other way to do this??
How to cast an int to a string I came across this code:
#include <iostream>
#include <string>
int main(){
double f = 23.43;
std::string f_str = std::to_string(f);
std::cout << f_str << '
';
}
Unfortunately, using Dev C++ Version 5.4.2, I'm getting an error:
[Error] 'to_string is not a member of 'std'
In my refference book I have got a example with a part saying to access the a[4][0] element of the array (named a) with pointer this can be written:
*((int*)a+4)
I wonder if the cast is really required. The book says it is required so that the pointer arithmetic can be done properly. However I am not sure about it. When I work with pointers defined by myself I don't use casts similar to this one. Is there a difference between a self defined pointer and array name?
I have this program.
Code:
int test_variable;
int main() {
test_variable = (int)0x12;
}
Now my doubt is what is the advantage of type casting 0x12 to int. suppose if the test_variable data type is "char" then should i type cast to "char"?
Code:
namespace ConsoleApplication1 {
class ImplicitlyConvertibleFromFoo {
public ImplicitlyConvertibleFromFoo(Foo foo) {
this.foo = foo;
}
Foo foo;
[code]....
Any way to easily convert arrays of user-defined types?
I am writing a program with FLTK and in event handling part wanted to send the address of the handler function to callback function. Type cast just does not work.
Code: btnOpenDB->callback(&FLUI::WndMain::DBOpenBtnClick_scb, reinterpret_cast<void*>(&WndMain::DBOpenBtnClick_cb));
I want to cast "a pointer to a class member function which accepts one argument" to a void pointer. After all it is just an address. So it is logically possible to cast it. Isn't it? Actually an static_cast should be enough!
The warning: :63:7: warning: passing argument 1 of fputc makes integer from pointer without a cast [enabled by default]
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/stat.h>
[Code]....
