Introduction -: The ANSI C++ standard add several new features to the original c++ specification. Some are added to provide better control in certain situation other are added for providing convenience to c++ programmers.
The important features are here as like
1 . New data type
- Bool
- wchar_t
2. New Operators
- const_cast
- static_cast
- dynamic_cast
- reinterpret_cast
- typeid
3. class implementation
- explicit constructor
- Mutable member
4. Namespace scope
5. Operator keyword
6.New keywords
7. New headers
New Data type-: The ANSI c++ added two new data type to enhance the range of data types available in c++. They are BOOL and wchar_t.
The Bool data type– the data type bool has been added to hold boolean value true or false. The value true and false have been added as keyword to the c++ language. the bool type variable can be declared as follows as like
bool b1; b1=true; bool b2= false; the default numeric value of true is 1 and false is 0 cout <<"b1= "<< b1; cout <<"b2= "<<b2; the output display the following b1=1 b2=0;
The wchar_r data type –: The character data type wchar_t has been defined in ANSI c++ to hold 16 bit wide character. 16 bit character are used to represent the character set of language that have more than 255 character.
ANSI c++ also introduce a new character literal known as wide_character literal which use two bytes of memory. It’s start the letter L as like..
L'xy' //wide character
New Operators-: We have used several operator in several program of c++ language.We know that the cast are used to convert the value from one type to another. This is necessary in situation where automatic conversion are not possible.
The static_cast operator -: This operator is used for any standard conversion data type . It can also be used to cast base class pointer into a derived class pointer. For like
static_cast <type>(object)
The const_cast operator-: It is used to explicitly override const or volatile in a cast . it takes as like
const_cast<type>(object)
The reinterpret_cast operator-: this is used to change one type into a fundamentally different type for example
reinterpret_cast<type>(object)
The dynamic cast operator-: It is used to type of an object at run-time. Its main application is to perform cast on polymorphic object. as like
dynamic_cast <type>(object)
The typeid operator -: this operator is use to obtain the types of unknown object such as their class name at runtime. for example
char *objectType =typeid(object).name();
Class implementation -: C++ add two unusual keywords Explicit and Mutable for use with class member.
Explicit keyword-: It is use for declare class construction to be “explicit ” constructors.
Mutable keyword-: A class object or a member function may be declared as const thus making their member data not modifiable.
Namespace scope –: C++ added added a new keyword namespace to define a scope that could hold global identifiers. Example of in c++ are class , function and templates are declared with the namespace namespace std.
Defining a namespace-: we can define a namespace in our program. the syntax for defining a namespace is similar to the syntax as like
namespace namespace_name
{
//declaration
}
Operator keywords -: C++ has several operator keyword. these are the
&& and !! OR ! NOT != NOT_EQ & BITAND | BITOR ^ XOR ~ COMPL &= AND_E1 |= OR_EQ ^= XOR_EQ
New Keyword- : c++ has support new several keyword.there are 64 keyword in c++ . as like auto,enum,new,this etc.
New Headers-: c++ has defined a new way to specify header files. They don’t use .h extension to filenames. as like
#include<iostream> #iclude<fstream>
More related topic is available here