This module offers a high-level and functional interface to the Format module of the OCaml standard library. It is a pretty-printing facility, i.e. it takes as input some code represented as a tree and formats this code into the most visually satisfying result, breaking and indenting lines of code where appropriate.

Input data must be first modelled and converted into a tree using 3 kinds of nodes:

• atoms
• lists
• labelled nodes

Atoms represent any text that is guaranteed to be printed as-is. Lists can model any sequence of items such as arrays of data or lists of definitions that are labelled with something like "int main", "let x =" or "x:".