Last week I've started working toward the new sequent interface. After a bit of brainstorming I've soon realized that to implement the new frontend I've to change the way I handle generic data types in the TWB.
At the moment generic data types (for example how formulae are represented) are barried inside the TWB library, making very painful for the user to add a new datatype or a new container (for example a queue of tuples). Decoupling my generic types from the TWB library is conceptually easy, but technically complicated because of the ocaml type system.
This week I've re-learned about polimorphic variants and read a number of paper from Jacques Garrigue