Complete Modern C++ - Mandatory Copy Elision - II

The video tutorial explains the concept of copy elision in C++ and its importance in avoiding unnecessary copying of temporary objects. It compares the behavior of copy elision in C++14 and C++17, highlighting that in C++17, copy elision is mandatory under certain conditions. The tutorial demonstrates how this feature can be beneficial, especially for objects that are expensive to copy, and discusses its application in factory functions. The video concludes by summarizing the key points about mandatory copy elision in C++17.

What is the main advantage of using C++17 over C++14 in terms of copy elision?

• C++17 allows optional copy elision.

• C++17 makes copy elision mandatory under certain conditions.

• C++17 requires explicit copy constructors.

• C++17 eliminates the need for any constructors.

In which scenario is mandatory copy elision applied in C++17?

• When an object is initialized by an L value.

• When a function accepts an R value as an argument.

• When a function returns a temporary by value.

• When a function returns an L value.

Why is mandatory copy elision beneficial for expensive-to-copy objects?

• It ensures objects are always copied.

• It allows for more complex factory functions.

• It guarantees no constructors are needed.

• It reduces the need for output parameters.

What happens when you switch from C++17 to C++14 regarding copy elision?

• Copy elision is always applied.

• Copy elision is not allowed.

• Copy elision becomes optional.

• Copy elision becomes mandatory.

Which of the following is NOT a condition for mandatory copy elision in C++17?

• A function returns an L value.

• A function accepts an L value with an R value argument.

• An object is initialized by an R value.

• A function returns a temporary by value.