The Copy Constructor

The copy constructor constructs an object which will be a copy of an existing object.
Prototype
```
    Type::Type(const Type&);
```
The copy constructor is used in the following situations.
- To create an object and initialize it to the value of an existing object.
- To create a local copy of a parameter that is passed by value to a function.
- To create a copy of the return value passed back from a function.
Do not confuse the notation of the copy constructor
```
    Rational r = s;
```
with the notation of the assignment operator
```
    r = s;
```
The Automatic Copy Constructor
- Allocates memory for the data members.
- Invokes each data member's copy constructor to copy values from the existing object.
Example - CopyConstructorTest.cpp, vector.h (original), vector.h(copy) , vector.cpp

This page was last modified on Feb 2, 2001

URL: http://people.hsc.edu/faculty-staff/robbk/Coms262/Lectures/CopyConstructor.html