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@ak9999
Created January 2, 2022 02:15
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Demo on using `const`.
#include <iostream>
static int outside_variable{0};
class Demo {
int val;
public:
static const int inside{1};
Demo(int v = 0) {
val = v;
}
void f1() {
std::cout << "f1()\n";
std::cout << "static int outside_variable: " << outside_variable << '\n';
}
void f2() const {
std::cout << "f2()\n";
int i = 0;
std::cout << "Current i: " << i << '\t';
++i;
std::cout << "Current i: " << i << '\t';
// ++outside_variable; // doesn't work
// Does work with const_cast
std::cout << "Current outside_variable: " << outside_variable << '\n';
++outside_variable;
// int &modifiable = const_cast <int &> (outside_variable);
// modifiable = 20;
std::cout << "Current outside_variable: " << outside_variable << '\n';
}
void f3() {
std::cout << "f3()\n";
std::cout << "static int inside: " << inside << '\n';
int& writable = const_cast<int&>(inside);
writable = 20;
std::cout << "static int inside: " << inside << '\n';
}
};
int main() {
const Demo d;
Demo c;
c.f1();
d.f2();
c.f1();
c.f3();
return 0;
}
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