.. _type-class-extensions:

Class and instances declarations
================================

This section documents GHC's type-class extensions.
There's lots of background in the paper `Type classes: exploring the
design
space <https://research.microsoft.com/~simonpj/Papers/type-class-design-space/>`__
(Simon Peyton Jones, Mark Jones, Erik Meijer).

.. toctree::
    :maxdepth: 1

    multi_param_type_classes
    undecidable_super_classes
    constrained_class_methods
    default_signatures
    nullary_type_classes
    functional_dependencies
    instances