how to understand arrow in C++11 when use function declaration [duplicate]

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• arrow operator (->) in function heading 2 answers

how to understand below c++11 code?

template <typename EF>
auto make_scope_exit(EF&& exit_function) -> scope_exit<EF> {
return scope_exit<typename std::remove_reference<EF>::type>
(std::forward<EF>(exit_function));
}