# 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 = [None, None, None] # sentinel node
root[0] = root[1] = root
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[:]
self.__root[:] = [self.__root, self.__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)
Diff to Previous Revision
--- revision 6 2010-03-27 10:00:14
+++ revision 7 2011-04-23 00:56:15
@@ -1,100 +1,257 @@
-from UserDict import DictMixin
-
-class OrderedDict(dict, DictMixin):
+# 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.__end
+ self.__root
except AttributeError:
- self.clear()
- self.update(*args, **kwds)
+ self.__root = root = [None, None, None] # sentinel node
+ root[0] = root[1] = root
+ 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):
- self.__end = end = []
- end += [None, end, end] # sentinel node for doubly linked list
- self.__map = {} # key --> [key, prev, next]
+ 'od.clear() -> None. Remove all items from od.'
+ try:
+ for node in self.__map.itervalues():
+ del node[:]
+ self.__root[:] = [self.__root, self.__root, None]
+ self.__map.clear()
+ except AttributeError:
+ pass
dict.clear(self)
- def __setitem__(self, key, value):
- if key not in self:
- end = self.__end
- curr = end[1]
- curr[2] = end[1] = self.__map[key] = [key, curr, end]
- dict.__setitem__(self, key, value)
-
- def __delitem__(self, key):
- dict.__delitem__(self, key)
- key, prev, next = self.__map.pop(key)
- prev[2] = next
- next[1] = prev
-
- def __iter__(self):
- end = self.__end
- curr = end[2]
- while curr is not end:
- yield curr[0]
- curr = curr[2]
-
- def __reversed__(self):
- end = self.__end
- curr = end[1]
- while curr is not end:
- yield curr[0]
- curr = curr[1]
-
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:
- key = reversed(self).next()
+ link = root[0]
+ link_prev = link[0]
+ link_prev[1] = root
+ root[0] = link_prev
else:
- key = iter(self).next()
- value = self.pop(key)
+ 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]
- tmp = self.__map, self.__end
- del self.__map, self.__end
inst_dict = vars(self).copy()
- self.__map, self.__end = tmp
+ for k in vars(OrderedDict()):
+ inst_dict.pop(k, None)
if inst_dict:
return (self.__class__, (items,), inst_dict)
return self.__class__, (items,)
- def keys(self):
- return list(self)
-
- setdefault = DictMixin.setdefault
- update = DictMixin.update
- pop = DictMixin.pop
- values = DictMixin.values
- items = DictMixin.items
- iterkeys = DictMixin.iterkeys
- itervalues = DictMixin.itervalues
- iteritems = DictMixin.iteritems
-
- def __repr__(self):
- if not self:
- return '%s()' % (self.__class__.__name__,)
- return '%s(%r)' % (self.__class__.__name__, self.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)
