FunctorT

The operations here are very similar to those in Recursive and Corecursive. The usual names (cata, ana, etc.) are prefixed with trans and behave generally the same, except 1. the A of the [un]fold is restricted to T[G], but 2. the [co]algebra shape is like F[A] => G[A] rather than F[A] => A.

In exchange, the [un]folds are available to more types (EG, folds available to Free and unfolds available to Cofree).

There are two additional operations – transCataT and transAnaT. The distinction between these and transCata/transAna is that this allows the algebra to return the context (the outer T) to be used, whereas transCata always uses the original context of the argument to f.

This is noticable when T is Cofree. In this function, the result may have any head the algebra desires, whereas in transCata, it can only have the head of the argument to f.

Docs for operations, since they seem to break scaladoc if put in the right place:

* map – very roughly like Uniplate’s descend * transCataT – akin to Uniplate’s transform * transAnaT – akin to Uniplate’s topDownTransform * transCata – akin to Fixplate’s restructure