Returning multiple values from a function is something very common, yet there is no first-class solution in C++ to enable it directly. Developers have to choose between returning multiple values through reference parameters to a function, defining a structure to contain the multiple values or returning a std::pair or std::tuple. The first two use named variables that have the advantage that they clearly indicate the meaning of the return value, but have the disadvantage that they have to be explicitly defined. std::pair has its members called first and second, and std::tuple has unnamed members that can only be retrieved with a function call, but can be copied to named variables using std::tie(). None of these solutions is ideal.

C++17 extends the semantic use of std::tie() into a first-class core language feature that enables unpacking the values of a tuple to named variables. This feature is called structured bindings.