C++14 - Tuple addressing via type

Today I would like to introduce one of new features which will arrive to C++ with new language standard (C++14) which is going to be release in 2014. In order to compile example from this article you need to have compiler supporting C++14 standard. The newest version of GCC supports it.

I would like to introduce you features called Tuple addressing via type which allows us to get tuple element value using type name instead of tuple parameter number. Of course it is possible only for type names which are not ambiguous. Let's take a look on below example for better understanding:
In point I we are declaring our tuple type containng of 2 int elements and on string element.

In point II we are using std::get function to get values of our tuple typed variable using tuple parameters numbers. This feature is well known from C++11 standard.

Point III shows new (introduced in C++14 standard) way of getting values of tuple elements. We are getting string type element using type name instead of putting parameter number. This can be more comfortable. Of course it is not possible to get int paramters values that way, because we have more than one int parameters in our tuple so tryting to get int element via type name is ambiguous. It is snown in commented code of point IV. If you uncomment this code and will try to compile example, you will receive compilation error.

Code of this example can find on our GitHub account here: https://github.com/xmementoit/CppAdventureExamples/tree/master/cpp14/tupleAddressingViaType

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