contiguous ranges

[Vlad Levenfeld via Digitalmars-d]

Since C++17, there's a new iterator category: the contiguous 
iterator. Check it out: http://en.cppreference.com/w/cpp/iterator

So, by extension, I think a ContiguousRange would be any 
RandomAccessRange which has a member called ptr which supports a 
dereferencing operator * that yields an ElementType!R. This 
notion is useful for functions which might otherwise perform an 
element-by-element transfer to an OutputRange via put, instead 
perform an optimized batch transfer directly to a ContiguousRange 
via ptr. (Not that Contiguous implies Output; this example 
assumes the ContigiousRange has enough length to accomodate the 
transfer or otherwise has mutable length, e.g. builtin arrays.)

I've been using the idea implicitly in my code with static if (is 
(typeof(*R.init.ptr) == ElementType!R)), but seeing that table 
made me realize it could be formally abstracted out to a range 
concept.