Universal Procedures
=====================

This section documents procedures that operate across all types rather than
being specific to a single data type. It is organised into three categories:
*predicate procedures*, which test objects for type membership or other
properties and return a boolean value; *comparison procedures*, which test
relationships between objects of any type using various notions of equality;
and *control features*, which provide facilities for applying procedures,
constructing them dynamically, and manipulating the flow of execution.
Together these procedures form the backbone of day-to-day Scheme programming,
and are used pervasively throughout code of all kinds.

.. toctree::
   :maxdepth: 1
   :caption: Contents:

   predicates
   comparisons
   control_features