Experimental sparse-array node 32-arity trie derived from Rich Hickey's work on Clojure tries. This is a much faster C++11 implementation with a larger repertoire of operations, including a O(m log n) SHL/SHR (where m is the number of spaces shifted) operation (arrays are O(n) SHL/SHR), and it is purely immutable. A library of immutable structures is planned, and it will be designed for a lock-free functional programming API with implicit concurrency. It may be reduced to C for portability.