What Is Rvalue Reference

Checks whether t is a rvalue reference type.

What is rvalue reference.

Such rvalue reference lets you modify the value of a temporary object. Provides the member constant value which is equal to true if t is a rvalue reference type. A rvalue reference can refer to rvalues. Const int ref 10.

To declare a rvalue reference we need to specify two operator i e. It s like removing the const attribute in the second line above. They are primarily meant to aid in the design of higer performance and more robust libraries. Here lvalueref2 is a lvalue reference so it cannot point to a rvalue.

So the following snippet works like a charm. Rvalue references is a small technical extension to the c language. Rvalue references are introduced in c 11 and rvalue references can do what lvalue references fails to do i e. The behavior of a program that adds specializations for is rvalue reference or is rvalue reference v since c 17 is undefined.

Rvalue references are a feature of c that was added with the c 11 standard. Let s play a bit with this new toy. Lvalue reference and rvalue reference. C 0x has introduced a new type called rvalue reference denoted by placing a double ampersand after some type.

Otherwise value is equal to false. An rvalue reference is a compound type very similar to c s traditional reference. What makes rvalue references a bit difficult to grasp is that when you first look at them it is not clear what their purpose is or what problems they solve. Rvalue references allow programmers to avoid logically unnecessary copying and to provide perfect forwarding functions.

To better distinguish these two types we refer to a traditional c reference as an lvalue reference.