- Rename elem to contains
- Rename subset to is_subset, and make is_subset applicable in infix notation
- Add the at_key method
- operator[] is now bound to at_key instead of find
- Rename bind to chain
- Rename mcompose to monadic_compose
- Rewrite a large part of the documentation
- Document the limit on the arity of functions used with monadic_compose
Fixes 48
Fixes 9