Ordered Set Recipe

class sortedcollections.OrderedSet(iterable=())

Like OrderedDict, OrderedSet maintains the insertion order of elements.

For example:

>>> ordered_set = OrderedSet('abcde')
>>> list(ordered_set) == list('abcde')
True
>>> ordered_set = OrderedSet('edcba')
>>> list(ordered_set) == list('edcba')
True

OrderedSet also implements the collections.Sequence interface.

__contains__(key)

key in ordered_set

__getitem__(index)

ordered_set[index] -> element; lookup element at index.

__init__(iterable=())

Initialize self. See help(type(self)) for accurate signature.

__iter__()

iter(ordered_set)

__len__()

len(ordered_set)

__repr__()

Text representation of set.

__reversed__()

reversed(ordered_set)

__str__()

Text representation of set.

__weakref__

list of weak references to the object (if defined)

add(value)

Add element, value, to set.

count(key)

key in ordered_set

discard(value)

Remove element, value, from set if it is a member.

index(value)

Return index of value.