stdmaketuple3

Stdmaketuple3 is a function found in some C++ standard library implementations, though it is not officially part of the C++ standard. Its primary purpose is to create a `std::tuple` object containing exactly three elements. The function typically takes three arguments, each representing an element of the tuple, and returns a `std::tuple` constructed from these arguments.

The existence and behavior of `std::maketuple3` are implementation-defined. This means that different C++ compilers or standard library versions might provide it, or they might not. If it is provided, it usually offers a more concise syntax for creating three-element tuples compared to explicitly calling the `std::tuple` constructor. For example, instead of writing `std::tuple<T1, T2, T3>(val1, val2, val3)`, one might be able to write `std::maketuple3(val1, val2, val3)`.

Because it is not a standard feature, relying on `std::maketuple3` can lead to code that is not portable across different C++ environments. The standard C++ way to achieve the same result is by using `std::make_tuple` with three arguments, or by directly constructing a `std::tuple` object. Developers are generally advised to use standard, portable features like `std::make_tuple` for creating tuples to ensure wider compatibility.