class myClass {
    public:
        myClass();
        myClass(const myClass &);
        myClass(const int, const int,
                const string &, const char *);
        myClass & operator=(const myClass &);
    private:
        ...
}

• They are always simply the class name and arguments to the constructor.
• The class name takes the place of, is, the function name.
• A method which has the same name as the class

• There are many types, though specifically, there are really only three types.
• Default
• Copy
• Other (special purpose)

        myClass();

• Identification
• No arguments.
• Usage
• Is called whenever you declare this type of variable without specifying another constructor.
myClass m;

        myClass(const myClass &);

• Identification
• Its one argument (type) is the class.

• Usage
• Is called whenever
• You declare a variable of this type using the assignment operator (=)

 

 

myClass j;

myClass m = j;     //    <--------
• You use the constructor notation with another variable of this class type.
 
myClass j;
myClass m(j);     //    <--------

        myClass(const int, const int,
            const string &, const char *);

• Identification
• It has any number of arguments
• no specific type

•  Usage
• Is called only when it is called directly...
 
myClass m(3, 4, "Directly", "because");

or

myClass m;
...
m = myClass(3, 4, "Directly", "later");

        myClass & operator=(const myClass &);

• Identification
• It uses operator overloading, otherwise looks quite similar to the copy constructor.

• Usage
• Just as you would use the normal = operator.

myClass m, j(5,4,"Example", "assignment");
m = j;

    myClass(const myClass &);
        myClass(const int, const int,
            const string &, const char *);
    myClass & operator=(const myClass &);
 

Why use const?

The parameter is not changing, and further SHOULD NOT change.

    myClass(const myClass &);
        myClass(const int, const int,
            const string &, const char *);
    myClass & operator=(const myClass &);
 

Why use reference parameters (myClass &, string &)?

The parameter is an object

Objects can be quite large

Passing by value COPIES the object when the function is called

large objects take a long time to copy