newClass(N,m) -- makes a copy of m with N as the new class
newClass(N,M,m) -- makes a copy of m with N as class and M as parent
If m is a list, then BasicList should be an ancestor of N. If m is a hash table, then HashTable should be an ancestor of N.
If m is mutable, and instances of class N are also mutable, then copying is not required, and is not done.
See also: