std::initializer_list<T>::initializer_list (3) - Linux Man Pages
initializer_list() noexcept; (since C++11)
constexpr initializer_list() noexcept; (since C++14)
Constructs an empty initializer list.
// Run this code
Despite a lack of constructors, it is possible to create non-empty initializer lists. Instances of std::initializer_list are implicitly constructed when:
* a braced-init-list is used in list-initialization, including function-call list initialization and assignment expressions (not to be confused with constructor_initializer_lists)
* a braced-init-list is bound to auto, including in a ranged_for_loop