tree 5e8fa8c0e79efbfe9c6a8271674f9599239ead70
parent 23bf894590be0af06c6cbd9ec391aaa86ec25683
author Jason Rhinelander <jason@imaginary.ca> 1499194661 -0400
committer Jason Rhinelander <jason@imaginary.ca> 1499272034 -0400

Combine std::tuple/std::pair logic

The std::pair caster can be written as a special case of the std::tuple
caster; this combines them via a base `tuple_caster` class (which is
essentially identical to the previous std::tuple caster).

This also removes the special empty tuple base case: returning an empty
tuple is relatively rare, and the base case still works perfectly well
even when the tuple types is an empty list.