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Full Discussion: Reference to a const
Top Forums Programming Reference to a const Post 82668 by RishiPahuja on Monday 5th of September 2005 06:20:00 AM
Old 09-05-2005
MySQL

Quote:
Originally Posted by arun.viswanath
Can any one explain how the statement '2' in the following statements is a legal one.

int & ref = 3; // Illegal statement - Compiler error.
const int& ref=3 ; // Compile and executes properly.


Thanks in Advance,
Arun

Arun,

value of '3' is a constant hence it can only be assigned to a const reference. below example will help you to understand better.

likewise say if you have:
int a=3;
int &b = a; //this is perfectly legal
const int &c = a; //this is legal

while if you had
const int a=3;
int &b = a; //illegal because : cannot convert from 'const int' to 'int &'
const int &c = a; //this is legal


rishi
 

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zipios::SimpleSmartPointer(3)				     Library Functions Manual				     zipios::SimpleSmartPointer(3)

NAME
zipios::SimpleSmartPointer - SimpleSmartPointer is a simple reference counting smart pointer template. SYNOPSIS
#include <simplesmartptr.h> Public Member Functions Type * operator-> () const Type & operator* () const SimpleSmartPointer (Type *p=0) template<class T2 > SimpleSmartPointer (const SimpleSmartPointer< T2 > &src) SimpleSmartPointer (const SimpleSmartPointer &src) template<class T2 > SimpleSmartPointer & operator= (const SimpleSmartPointer< T2 > &src) SimpleSmartPointer & operator= (const SimpleSmartPointer &src) SimpleSmartPointer & operator= (Type *src) bool operator== (const Type *p) const bool operator!= (const Type *p) const bool operator== (const SimpleSmartPointer &sp) const bool operator!= (const SimpleSmartPointer &sp) const bool operator! () const operator void * () const Type * get () const unsigned int getReferenceCount () const Returns the reference count - For debugging purposes. Detailed Description template<class Type>class zipios::SimpleSmartPointer< Type > SimpleSmartPointer is a simple reference counting smart pointer template. The type pointed to must keep a reference count that is accessible through the two methods void ref() const and unsigned int unref() const. The type must also handle the reference count properly. The easiest way to do that is to use the ReferenceCount template class. Definition at line 15 of file simplesmartptr.h. Member Function Documentation template<class Type> unsigned int zipios::SimpleSmartPointer< Type >::getReferenceCount () const [inline] Returns the reference count - For debugging purposes. Definition at line 67 of file simplesmartptr.h. Author Generated automatically by Doxygen for Zipios++ from the source code. Zipios++ Mon Oct 10 2011 zipios::SimpleSmartPointer(3)
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