Lvalue reference declarator: &
Holds the address of an object but behaves syntactically like an object.
Syntax
lvalue-reference-type-id
:
type-specifier-seq
&
attribute-specifier-seq
opt ptr-abstract-declarator
opt
Remarks
You can think of an lvalue reference as another name for an object. An lvalue reference declaration consists of an optional list of specifiers followed by a reference declarator. A reference must be initialized and cannot be changed.
Any object whose address can be converted to a given pointer type can also be converted to the similar reference type. For example, any object whose address can be converted to type char *
can also be converted to type char &
.
Don't confuse reference declarations with use of the address-of operator. When the &
identifier is preceded by a type, such as int
or char
, identifier is declared as a reference to the type. When &
identifier is not preceded by a type, the usage is that of the address-of operator.
Example
The following example demonstrates the reference declarator by declaring a Person
object and a reference to that object. Because rFriend
is a reference to myFriend
, updating either variable changes the same object.
// reference_declarator.cpp
// compile with: /EHsc
// Demonstrates the reference declarator.
#include <iostream>
using namespace std;
struct Person
{
char* Name;
short Age;
};
int main()
{
// Declare a Person object.
Person myFriend;
// Declare a reference to the Person object.
Person& rFriend = myFriend;
// Set the fields of the Person object.
// Updating either variable changes the same object.
myFriend.Name = "Bill";
rFriend.Age = 40;
// Print the fields of the Person object to the console.
cout << rFriend.Name << " is " << myFriend.Age << endl;
}
Bill is 40
See also
References
Reference-type function arguments
Reference-type function returns
References to pointers