Why does initialization of array of pairs still need double braces in C++14?

Question

With the C++14 standard, the initialization of an std::array can go with single braces (see http://en.cppreference.com/w/cpp/container/array):

This, however

Answer 1

I'm going to guess here.
The initializer list for std::array should be a list of T (or trivially constructable to T). So you could do

std::array,3> b { std::pair{1,11}, std::pair{2,22}, std::pair{3,33} };

but that is tediously verbose. In order to get the conversion to std::pair you want, you need to provide an initializer list, so

std::array,3> b {
    { // element 1
      { // initialize from:
        { 1,11 } // std::initializer_list
       }
     },
  ...
};

I can't defend this further, but note that std::vector::vector( std::initializer_list, const Allocator& alloc=Allocator()) is defined but std::array::array( std::initializer_list ) is not. Neither is std::pair::pair( std::initializer_list ) defined.