Contains functions to automatically create instances from data type definitions.
Generates all possible instances of a, while using no more than n levels of recursion. Each subtype requires another level of recursion. For example:
Branch (Branch Leaf 17) (Leaf 3)
would require 4 levels of recursion. One for the first branch, one for second branch, one for the left Leaf, and one for the Int (the seventeen). The right part of the first branch (Left 3) would be done in two recursions.
Creates an instance of a Haskell type. For this to work the compiler must be able to deduce the type from the callee's context.
createInstance excepts it uses a phantom type to elicit the
correct type to return.