Module Common.Foldable

This module follows the Jane Street organisation and naming conventions for 'standard interfaces' i.e. commonly used signatures; briefly:

• Basic defines the _minimal_ set of type and function signatures that a user must provide
• S defines the _complete_ set of type and functions signatures that will be exposed by any module supporting the standard interface associated with S
• Make is a functor (i.e. a function from module to module) that takes the user supplied Basic module and returns a completed module with the signature defined by S

Where a standard interface is defined for difference arities of type constructors, the convention is to append the arity to the names of the signatures and functors e.g. Basic2, S2 and Make2