This document describes the current stable version of Kombu (4.1). For development docs, go here.

Functional-style Utilities - kombu.utils.functional

Functional Utilities.

class kombu.utils.functional.LRUCache(limit=None)

LRU Cache implementation using a doubly linked list to track access.

Parameters:limit (int) – The maximum number of keys to keep in the cache. When a new key is inserted and the limit has been exceeded, the Least Recently Used key will be discarded from the cache.

incr(key, delta=1)

items()

iteritems()

iterkeys()

itervalues()

keys()

popitem(last=True)

update(*args, **kwargs)

values()

kombu.utils.functional.memoize(maxsize=None, keyfun=None, Cache=<class 'kombu.utils.functional.LRUCache'>)

Decorator to cache function return value.

class kombu.utils.functional.lazy(fun, *args, **kwargs)

Holds lazy evaluation.

Evaluated when called or if the evaluate() method is called. The function is re-evaluated on every call.

Overloaded operations that will evaluate the promise:

__str__(), __repr__(), __cmp__().

evaluate()

kombu.utils.functional.maybe_evaluate(value)

Evaluate value only if value is a lazy instance.

kombu.utils.functional.is_list(l, scalars=(<class 'collections.abc.Mapping'>, <class 'str'>), iters=(<class 'collections.abc.Iterable'>, ))

Return true if the object is iterable.

Note

Returns false if object is a mapping or string.

kombu.utils.functional.maybe_list(l, scalars=(<class 'collections.abc.Mapping'>, <class 'str'>))

Return list of one element if l is a scalar.

kombu.utils.functional.dictfilter(d=None, **kw)

Remove all keys from dict d whose value is None.