C++ Syntax that You May Have Forgotten

Remembering a bunch of C++ syntax can make you "loopy." The following samples show the syntax of some of the more easily forgotten C++ situations: a for loop, a while loop, and a switch statement; a class and the code for a member function; a base class and a derived class; a function, function pointer type, and pointer to the function; and a class template and then a class based on the template.

Here’s a for loop:

int i;
for (i=0; i<10; i++) {
    cout << i << endl;
}

Here’s a while loop that counts from 10 down to 1:

int i = 10;
while (i > 0) {
    cout << i << endl;
    i—;
}

And here’s a switch statement:

switch (x) {
case 1:
    cout << “1” << endl;
case 2:
    cout << “2” << endl;
default:
    cout << “Something else” << endl;
}

Here’s a class and the code for a member function:

class MyClass {
private:
    int x;
public:
    void MyFunction(int y);
};
void MyClass::MyFunction(int y) {
    x = y;
}

Here’s a base class and a derived class:

class MyBase {
private:
   // derived classes can
   // not access this
   int a;   
protected:
   // derived classes can 
   // access this
   int b;   
};
class Derived : public MyBase {
public:
    void test() {
        b = 10;
    }
};

Here’s a function, a function pointer type, and a pointer to the function:

int function(char x) {
    return (int)x;
}
typedef int (* funcptr)(char);
funcptr MyPtr = function;

And here’s a class template and then a class based on the template:

template <typename T>
class MyTemplate {
public:
    T a;
};
MyTemplate<int> X;