262 lines
8.7 KiB
Python
262 lines
8.7 KiB
Python
# Downloaded from http://code.activestate.com/recipes/576693/
|
|
# Licensed under the MIT License
|
|
|
|
# Backport of OrderedDict() class that runs on Python 2.4, 2.5, 2.6, 2.7 and pypy.
|
|
# Passes Python2.7's test suite and incorporates all the latest updates.
|
|
|
|
try:
|
|
from thread import get_ident as _get_ident
|
|
except ImportError:
|
|
from dummy_thread import get_ident as _get_ident
|
|
|
|
try:
|
|
from _abcoll import KeysView, ValuesView, ItemsView
|
|
except ImportError:
|
|
pass
|
|
|
|
|
|
class OrderedDict(dict):
|
|
'Dictionary that remembers insertion order'
|
|
# An inherited dict maps keys to values.
|
|
# The inherited dict provides __getitem__, __len__, __contains__, and get.
|
|
# The remaining methods are order-aware.
|
|
# Big-O running times for all methods are the same as for regular dictionaries.
|
|
|
|
# The internal self.__map dictionary maps keys to links in a doubly linked list.
|
|
# The circular doubly linked list starts and ends with a sentinel element.
|
|
# The sentinel element never gets deleted (this simplifies the algorithm).
|
|
# Each link is stored as a list of length three: [PREV, NEXT, KEY].
|
|
|
|
def __init__(self, *args, **kwds):
|
|
'''Initialize an ordered dictionary. Signature is the same as for
|
|
regular dictionaries, but keyword arguments are not recommended
|
|
because their insertion order is arbitrary.
|
|
|
|
'''
|
|
if len(args) > 1:
|
|
raise TypeError('expected at most 1 arguments, got %d' % len(args))
|
|
try:
|
|
self.__root
|
|
except AttributeError:
|
|
self.__root = root = [] # sentinel node
|
|
root[:] = [root, root, None]
|
|
self.__map = {}
|
|
self.__update(*args, **kwds)
|
|
|
|
def __setitem__(self, key, value, dict_setitem=dict.__setitem__):
|
|
'od.__setitem__(i, y) <==> od[i]=y'
|
|
# Setting a new item creates a new link which goes at the end of the linked
|
|
# list, and the inherited dictionary is updated with the new key/value pair.
|
|
if key not in self:
|
|
root = self.__root
|
|
last = root[0]
|
|
last[1] = root[0] = self.__map[key] = [last, root, key]
|
|
dict_setitem(self, key, value)
|
|
|
|
def __delitem__(self, key, dict_delitem=dict.__delitem__):
|
|
'od.__delitem__(y) <==> del od[y]'
|
|
# Deleting an existing item uses self.__map to find the link which is
|
|
# then removed by updating the links in the predecessor and successor nodes.
|
|
dict_delitem(self, key)
|
|
link_prev, link_next, key = self.__map.pop(key)
|
|
link_prev[1] = link_next
|
|
link_next[0] = link_prev
|
|
|
|
def __iter__(self):
|
|
'od.__iter__() <==> iter(od)'
|
|
root = self.__root
|
|
curr = root[1]
|
|
while curr is not root:
|
|
yield curr[2]
|
|
curr = curr[1]
|
|
|
|
def __reversed__(self):
|
|
'od.__reversed__() <==> reversed(od)'
|
|
root = self.__root
|
|
curr = root[0]
|
|
while curr is not root:
|
|
yield curr[2]
|
|
curr = curr[0]
|
|
|
|
def clear(self):
|
|
'od.clear() -> None. Remove all items from od.'
|
|
try:
|
|
for node in self.__map.itervalues():
|
|
del node[:]
|
|
root = self.__root
|
|
root[:] = [root, root, None]
|
|
self.__map.clear()
|
|
except AttributeError:
|
|
pass
|
|
dict.clear(self)
|
|
|
|
def popitem(self, last=True):
|
|
'''od.popitem() -> (k, v), return and remove a (key, value) pair.
|
|
Pairs are returned in LIFO order if last is true or FIFO order if false.
|
|
|
|
'''
|
|
if not self:
|
|
raise KeyError('dictionary is empty')
|
|
root = self.__root
|
|
if last:
|
|
link = root[0]
|
|
link_prev = link[0]
|
|
link_prev[1] = root
|
|
root[0] = link_prev
|
|
else:
|
|
link = root[1]
|
|
link_next = link[1]
|
|
root[1] = link_next
|
|
link_next[0] = root
|
|
key = link[2]
|
|
del self.__map[key]
|
|
value = dict.pop(self, key)
|
|
return key, value
|
|
|
|
# -- the following methods do not depend on the internal structure --
|
|
|
|
def keys(self):
|
|
'od.keys() -> list of keys in od'
|
|
return list(self)
|
|
|
|
def values(self):
|
|
'od.values() -> list of values in od'
|
|
return [self[key] for key in self]
|
|
|
|
def items(self):
|
|
'od.items() -> list of (key, value) pairs in od'
|
|
return [(key, self[key]) for key in self]
|
|
|
|
def iterkeys(self):
|
|
'od.iterkeys() -> an iterator over the keys in od'
|
|
return iter(self)
|
|
|
|
def itervalues(self):
|
|
'od.itervalues -> an iterator over the values in od'
|
|
for k in self:
|
|
yield self[k]
|
|
|
|
def iteritems(self):
|
|
'od.iteritems -> an iterator over the (key, value) items in od'
|
|
for k in self:
|
|
yield (k, self[k])
|
|
|
|
def update(*args, **kwds):
|
|
'''od.update(E, **F) -> None. Update od from dict/iterable E and F.
|
|
|
|
If E is a dict instance, does: for k in E: od[k] = E[k]
|
|
If E has a .keys() method, does: for k in E.keys(): od[k] = E[k]
|
|
Or if E is an iterable of items, does: for k, v in E: od[k] = v
|
|
In either case, this is followed by: for k, v in F.items(): od[k] = v
|
|
|
|
'''
|
|
if len(args) > 2:
|
|
raise TypeError('update() takes at most 2 positional '
|
|
'arguments (%d given)' % (len(args),))
|
|
elif not args:
|
|
raise TypeError('update() takes at least 1 argument (0 given)')
|
|
self = args[0]
|
|
# Make progressively weaker assumptions about "other"
|
|
other = ()
|
|
if len(args) == 2:
|
|
other = args[1]
|
|
if isinstance(other, dict):
|
|
for key in other:
|
|
self[key] = other[key]
|
|
elif hasattr(other, 'keys'):
|
|
for key in other.keys():
|
|
self[key] = other[key]
|
|
else:
|
|
for key, value in other:
|
|
self[key] = value
|
|
for key, value in kwds.items():
|
|
self[key] = value
|
|
|
|
__update = update # let subclasses override update without breaking __init__
|
|
|
|
__marker = object()
|
|
|
|
def pop(self, key, default=__marker):
|
|
'''od.pop(k[,d]) -> v, remove specified key and return the corresponding value.
|
|
If key is not found, d is returned if given, otherwise KeyError is raised.
|
|
|
|
'''
|
|
if key in self:
|
|
result = self[key]
|
|
del self[key]
|
|
return result
|
|
if default is self.__marker:
|
|
raise KeyError(key)
|
|
return default
|
|
|
|
def setdefault(self, key, default=None):
|
|
'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
|
|
if key in self:
|
|
return self[key]
|
|
self[key] = default
|
|
return default
|
|
|
|
def __repr__(self, _repr_running={}):
|
|
'od.__repr__() <==> repr(od)'
|
|
call_key = id(self), _get_ident()
|
|
if call_key in _repr_running:
|
|
return '...'
|
|
_repr_running[call_key] = 1
|
|
try:
|
|
if not self:
|
|
return '%s()' % (self.__class__.__name__,)
|
|
return '%s(%r)' % (self.__class__.__name__, self.items())
|
|
finally:
|
|
del _repr_running[call_key]
|
|
|
|
def __reduce__(self):
|
|
'Return state information for pickling'
|
|
items = [[k, self[k]] for k in self]
|
|
inst_dict = vars(self).copy()
|
|
for k in vars(OrderedDict()):
|
|
inst_dict.pop(k, None)
|
|
if inst_dict:
|
|
return (self.__class__, (items,), inst_dict)
|
|
return self.__class__, (items,)
|
|
|
|
def copy(self):
|
|
'od.copy() -> a shallow copy of od'
|
|
return self.__class__(self)
|
|
|
|
@classmethod
|
|
def fromkeys(cls, iterable, value=None):
|
|
'''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S
|
|
and values equal to v (which defaults to None).
|
|
|
|
'''
|
|
d = cls()
|
|
for key in iterable:
|
|
d[key] = value
|
|
return d
|
|
|
|
def __eq__(self, other):
|
|
'''od.__eq__(y) <==> od==y. Comparison to another OD is order-sensitive
|
|
while comparison to a regular mapping is order-insensitive.
|
|
|
|
'''
|
|
if isinstance(other, OrderedDict):
|
|
return len(self)==len(other) and self.items() == other.items()
|
|
return dict.__eq__(self, other)
|
|
|
|
def __ne__(self, other):
|
|
return not self == other
|
|
|
|
# -- the following methods are only used in Python 2.7 --
|
|
|
|
def viewkeys(self):
|
|
"od.viewkeys() -> a set-like object providing a view on od's keys"
|
|
return KeysView(self)
|
|
|
|
def viewvalues(self):
|
|
"od.viewvalues() -> an object providing a view on od's values"
|
|
return ValuesView(self)
|
|
|
|
def viewitems(self):
|
|
"od.viewitems() -> a set-like object providing a view on od's items"
|
|
return ItemsView(self)
|