Here are a few title options that capture the essence of your explanation and adhere to the question format: Option 1 (More direct): Why are Const References Allowed to Bind to Rvalues in C ? Optio

Const References and Rvalue References

This question revolves around the concept of const references and their ability to extend the lifetime of temporary objects in C . Specifically, it investigates why passing rvalues (temporary objects) by const reference is permitted, while normal references do not allow for this.

In the provided example:

<code class="cpp">void display(const int& a)
{
    cout << a ;
}</code>

This function can be called with a literal like display(5); without any issues. However, if the const keyword is removed, it will fail. This behavior arises because a const reference prolongs the lifespan of ephemeral values until the end of the containing scope, effectively extending their existence beyond their normal immediate scope. Moreover, this extension is achieved without the additional overhead of copy construction that would occur with a regular local variable.

In essence, a const reference provides a means of referencing rvalues while preserving their temporary nature, offering a highly performant and convenient mechanism for working with these objects.

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