I would start with lisp flavored erlang, and add clojure's immutable yet fast-copy data structures. They are based on work by Phil Bagwell, https://en.wikiped

I would start with lisp flavored erlang, and add clojure's immutable yet fast-copy data structures. They are based on work by Phil Bagwell, https://en.wikipedia.org/wiki/Hash_array_mapped_trie https://en.wikipedia.org/wiki/Hash_array_mapped_trie http://infoscience.epfl.ch/record/64398/files/idealhashtrees.pdf http://infoscience.epfl.ch/record/64398/files/idealhashtrees... You might do better to create a Lisp Flavored Haskell (if one hasn't been started already). I'm sure haskeller's would be offended by the idea, but it already uses HAMT.