What is a modifier in C++?
A modifier, also called a modifying function is a member function that changes the
value of at least one data member. In other words, an operation that modifies the
state of an object. Modifiers are also known as ‘mutators’.
Example: The function mod is a modifier in the following code snippet:
class test
{
int x, y;
public:
test()
{
x = 0; y = 0;
}
void mod()
{
x = 10;
y = 15;
}
};
What is an accessor in C++?
An accessor is a class operation that does not modify the state of an object in
C++. The accessor functions need to be declared as const operations
Differentiate between a template class and class template in C++?
Template class: A generic definition or a parametrized class not instantiated until
the client provides the needed information. It’s jargon for plain templates.
Class template: A class template specifies how individual classes can be constructed
much like the way a class specifies how individual objects can be constructed. It’s
jargon for plain classes.
Define namespace in C++?
It is a feature in C++ to minimize name collisions in the global name space. This
namespace keyword assigns a distinct name to a library that allows other libraries
to use the same identifier names without creating any name collisions. Furthermore,
the compiler uses the namespace signature for differentiating the definitions.
What is the use of ‘using’ declaration in C++?
A using declaration in C++ makes it possible to use a name from a namespace without
the scope operator.
What is an Iterator class in C++?
A class that is used to traverse through the objects maintained by a container class.
There are five categories of iterators: input iterators, output iterators, forward
iterators, bidirectional iterators, random access. An iterator is an entity that
gives access to the contents of a container object without violating encapsulation
constraints. Access to the contents is granted on a one-at-a-time basis in order.
The order can be storage order (as in lists and queues) or some arbitrary order
(as in array indices) or according to some ordering relation (as in an ordered binary
tree). The iterator is a construct, which provides an interface that, when called,
yields either the next element in the container, or some value denoting the fact
that there are no more elements to examine. Iterators hide the details of access
to and update of the elements of a container class.
The simplest and safest iterators are those that permit read-only access to the
contents of a container class.
What is an incomplete type in C++?
Incomplete types refers to pointers in which there is non availability of the implementation
of the referenced location or it points to some location whose value is not available
for modification.
int* i = NULL // i points to NULL
*i = 0; // Result in exception.
Incomplete types are otherwise called uninitialized pointers.