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# Copyright 2015-2016, Google Inc.
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"""Interfaces related to streams of values or objects."""
import abc
import six
class Consumer(six.with_metaclass(abc.ABCMeta)):
"""Interface for consumers of finite streams of values or objects."""
@abc.abstractmethod
def consume(self, value):
"""Accepts a value.
Args:
value: Any value accepted by this Consumer.
"""
raise NotImplementedError()
@abc.abstractmethod
def terminate(self):
"""Indicates to this Consumer that no more values will be supplied."""
raise NotImplementedError()
@abc.abstractmethod
def consume_and_terminate(self, value):
"""Supplies a value and signals that no more values will be supplied.
Args:
value: Any value accepted by this Consumer.
"""
raise NotImplementedError()