Class Predicate

source code

object --+
         |
        Predicate

base class for selector classes providing implementation
for operators ``&``, ``|`` and  ``~``

This class is only here to give access to binary operators, the selector
logic itself should be implemented in the :meth:`__call__` method. Notice it
should usually accept any arbitrary arguments (the context), though that may
vary depending on your usage of the registry.

a selector is called to help choosing the correct object for a
particular context by returning a score (`int`) telling how well
the implementation given as first argument fit to the given context.

0 score means that the class doesn't apply.

search for the given selector, selector instance or tuple of
selectors in the selectors tree. Return None if not found.