mirror of
https://github.com/python/cpython.git
synced 2025-10-31 13:41:24 +00:00
1098 lines
40 KiB
Python
1098 lines
40 KiB
Python
__all__ = ['deque', 'defaultdict', 'namedtuple', 'UserDict', 'UserList',
|
|
'UserString', 'Counter', 'OrderedDict']
|
|
|
|
# For backwards compatibility, continue to make the collections ABCs
|
|
# available through the collections module.
|
|
from collections.abc import *
|
|
import collections.abc
|
|
__all__ += collections.abc.__all__
|
|
|
|
from _collections import deque, defaultdict
|
|
from operator import itemgetter as _itemgetter
|
|
from keyword import iskeyword as _iskeyword
|
|
import sys as _sys
|
|
import heapq as _heapq
|
|
from weakref import proxy as _proxy
|
|
from itertools import repeat as _repeat, chain as _chain, starmap as _starmap
|
|
from reprlib import recursive_repr as _recursive_repr
|
|
|
|
################################################################################
|
|
### OrderedDict
|
|
################################################################################
|
|
|
|
class _Link(object):
|
|
__slots__ = 'prev', 'next', 'key', '__weakref__'
|
|
|
|
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 regular dictionaries.
|
|
|
|
# The internal self.__map dict 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).
|
|
# The sentinel is in self.__hardroot with a weakref proxy in self.__root.
|
|
# The prev/next links are weakref proxies (to prevent circular references).
|
|
# Individual links are kept alive by the hard reference in self.__map.
|
|
# Those hard references disappear when a key is deleted from an OrderedDict.
|
|
|
|
def __init__(self, *args, **kwds):
|
|
'''Initialize an ordered dictionary. The signature is the same as
|
|
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.__hardroot = _Link()
|
|
self.__root = root = _proxy(self.__hardroot)
|
|
root.prev = root.next = root
|
|
self.__map = {}
|
|
self.__update(*args, **kwds)
|
|
|
|
def __setitem__(self, key, value,
|
|
dict_setitem=dict.__setitem__, proxy=_proxy, Link=_Link):
|
|
'od.__setitem__(i, y) <==> od[i]=y'
|
|
# Setting a new item creates a new link at the end of the linked list,
|
|
# and the inherited dictionary is updated with the new key/value pair.
|
|
if key not in self:
|
|
self.__map[key] = link = Link()
|
|
root = self.__root
|
|
last = root.prev
|
|
link.prev, link.next, link.key = last, root, key
|
|
last.next = link
|
|
root.prev = proxy(link)
|
|
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 gets
|
|
# removed by updating the links in the predecessor and successor nodes.
|
|
dict_delitem(self, key)
|
|
link = self.__map.pop(key)
|
|
link_prev = link.prev
|
|
link_next = link.next
|
|
link_prev.next = link_next
|
|
link_next.prev = link_prev
|
|
|
|
def __iter__(self):
|
|
'od.__iter__() <==> iter(od)'
|
|
# Traverse the linked list in order.
|
|
root = self.__root
|
|
curr = root.next
|
|
while curr is not root:
|
|
yield curr.key
|
|
curr = curr.next
|
|
|
|
def __reversed__(self):
|
|
'od.__reversed__() <==> reversed(od)'
|
|
# Traverse the linked list in reverse order.
|
|
root = self.__root
|
|
curr = root.prev
|
|
while curr is not root:
|
|
yield curr.key
|
|
curr = curr.prev
|
|
|
|
def clear(self):
|
|
'od.clear() -> None. Remove all items from od.'
|
|
root = self.__root
|
|
root.prev = root.next = root
|
|
self.__map.clear()
|
|
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.prev
|
|
link_prev = link.prev
|
|
link_prev.next = root
|
|
root.prev = link_prev
|
|
else:
|
|
link = root.next
|
|
link_next = link.next
|
|
root.next = link_next
|
|
link_next.prev = root
|
|
key = link.key
|
|
del self.__map[key]
|
|
value = dict.pop(self, key)
|
|
return key, value
|
|
|
|
def move_to_end(self, key, last=True):
|
|
'''Move an existing element to the end (or beginning if last==False).
|
|
|
|
Raises KeyError if the element does not exist.
|
|
When last=True, acts like a fast version of self[key]=self.pop(key).
|
|
|
|
'''
|
|
link = self.__map[key]
|
|
link_prev = link.prev
|
|
link_next = link.next
|
|
link_prev.next = link_next
|
|
link_next.prev = link_prev
|
|
root = self.__root
|
|
if last:
|
|
last = root.prev
|
|
link.prev = last
|
|
link.next = root
|
|
last.next = root.prev = link
|
|
else:
|
|
first = root.next
|
|
link.prev = root
|
|
link.next = first
|
|
root.next = first.prev = link
|
|
|
|
def __sizeof__(self):
|
|
sizeof = _sys.getsizeof
|
|
n = len(self) + 1 # number of links including root
|
|
size = sizeof(self.__dict__) # instance dictionary
|
|
size += sizeof(self.__map) * 2 # internal dict and inherited dict
|
|
size += sizeof(self.__hardroot) * n # link objects
|
|
size += sizeof(self.__root) * n # proxy objects
|
|
return size
|
|
|
|
update = __update = MutableMapping.update
|
|
keys = MutableMapping.keys
|
|
values = MutableMapping.values
|
|
items = MutableMapping.items
|
|
__ne__ = MutableMapping.__ne__
|
|
|
|
__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
|
|
|
|
@_recursive_repr()
|
|
def __repr__(self):
|
|
'od.__repr__() <==> repr(od)'
|
|
if not self:
|
|
return '%s()' % (self.__class__.__name__,)
|
|
return '%s(%r)' % (self.__class__.__name__, list(self.items()))
|
|
|
|
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.
|
|
If not specified, the value defaults to None.
|
|
|
|
'''
|
|
self = cls()
|
|
for key in iterable:
|
|
self[key] = value
|
|
return self
|
|
|
|
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 \
|
|
all(p==q for p, q in zip(self.items(), other.items()))
|
|
return dict.__eq__(self, other)
|
|
|
|
|
|
################################################################################
|
|
### namedtuple
|
|
################################################################################
|
|
|
|
_class_template = '''\
|
|
from builtins import property as _property, tuple as _tuple
|
|
from operator import itemgetter as _itemgetter
|
|
from collections import OrderedDict
|
|
|
|
class {typename}(tuple):
|
|
'{typename}({arg_list})'
|
|
|
|
__slots__ = ()
|
|
|
|
_fields = {field_names!r}
|
|
|
|
def __new__(_cls, {arg_list}):
|
|
'Create new instance of {typename}({arg_list})'
|
|
return _tuple.__new__(_cls, ({arg_list}))
|
|
|
|
@classmethod
|
|
def _make(cls, iterable, new=tuple.__new__, len=len):
|
|
'Make a new {typename} object from a sequence or iterable'
|
|
result = new(cls, iterable)
|
|
if len(result) != {num_fields:d}:
|
|
raise TypeError('Expected {num_fields:d} arguments, got %d' % len(result))
|
|
return result
|
|
|
|
def __repr__(self):
|
|
'Return a nicely formatted representation string'
|
|
return self.__class__.__name__ + '({repr_fmt})' % self
|
|
|
|
def _asdict(self):
|
|
'Return a new OrderedDict which maps field names to their values'
|
|
return OrderedDict(zip(self._fields, self))
|
|
|
|
__dict__ = property(_asdict)
|
|
|
|
def _replace(_self, **kwds):
|
|
'Return a new {typename} object replacing specified fields with new values'
|
|
result = _self._make(map(kwds.pop, {field_names!r}, _self))
|
|
if kwds:
|
|
raise ValueError('Got unexpected field names: %r' % list(kwds))
|
|
return result
|
|
|
|
def __getnewargs__(self):
|
|
'Return self as a plain tuple. Used by copy and pickle.'
|
|
return tuple(self)
|
|
|
|
{field_defs}
|
|
'''
|
|
|
|
_repr_template = '{name}=%r'
|
|
|
|
_field_template = '''\
|
|
{name} = _property(_itemgetter({index:d}), doc='Alias for field number {index:d}')
|
|
'''
|
|
|
|
def namedtuple(typename, field_names, verbose=False, rename=False):
|
|
"""Returns a new subclass of tuple with named fields.
|
|
|
|
>>> Point = namedtuple('Point', ['x', 'y'])
|
|
>>> Point.__doc__ # docstring for the new class
|
|
'Point(x, y)'
|
|
>>> p = Point(11, y=22) # instantiate with positional args or keywords
|
|
>>> p[0] + p[1] # indexable like a plain tuple
|
|
33
|
|
>>> x, y = p # unpack like a regular tuple
|
|
>>> x, y
|
|
(11, 22)
|
|
>>> p.x + p.y # fields also accessable by name
|
|
33
|
|
>>> d = p._asdict() # convert to a dictionary
|
|
>>> d['x']
|
|
11
|
|
>>> Point(**d) # convert from a dictionary
|
|
Point(x=11, y=22)
|
|
>>> p._replace(x=100) # _replace() is like str.replace() but targets named fields
|
|
Point(x=100, y=22)
|
|
|
|
"""
|
|
|
|
# Parse and validate the field names. Validation serves two purposes,
|
|
# generating informative error messages and preventing template injection attacks.
|
|
if isinstance(field_names, str):
|
|
field_names = field_names.replace(',', ' ').split() # names separated by whitespace and/or commas
|
|
field_names = list(map(str, field_names))
|
|
if rename:
|
|
seen = set()
|
|
for index, name in enumerate(field_names):
|
|
if (not all(c.isalnum() or c=='_' for c in name)
|
|
or _iskeyword(name)
|
|
or not name
|
|
or name[0].isdigit()
|
|
or name.startswith('_')
|
|
or name in seen):
|
|
field_names[index] = '_%d' % index
|
|
seen.add(name)
|
|
for name in [typename] + field_names:
|
|
if not all(c.isalnum() or c=='_' for c in name):
|
|
raise ValueError('Type names and field names can only contain alphanumeric characters and underscores: %r' % name)
|
|
if _iskeyword(name):
|
|
raise ValueError('Type names and field names cannot be a keyword: %r' % name)
|
|
if name[0].isdigit():
|
|
raise ValueError('Type names and field names cannot start with a number: %r' % name)
|
|
seen = set()
|
|
for name in field_names:
|
|
if name.startswith('_') and not rename:
|
|
raise ValueError('Field names cannot start with an underscore: %r' % name)
|
|
if name in seen:
|
|
raise ValueError('Encountered duplicate field name: %r' % name)
|
|
seen.add(name)
|
|
|
|
# Fill-in the class template
|
|
class_definition = _class_template.format(
|
|
typename = typename,
|
|
field_names = tuple(field_names),
|
|
num_fields = len(field_names),
|
|
arg_list = repr(tuple(field_names)).replace("'", "")[1:-1],
|
|
repr_fmt = ', '.join(_repr_template.format(name=name) for name in field_names),
|
|
field_defs = '\n'.join(_field_template.format(index=index, name=name)
|
|
for index, name in enumerate(field_names))
|
|
)
|
|
|
|
# Execute the template string in a temporary namespace and
|
|
# support tracing utilities by setting a value for frame.f_globals['__name__']
|
|
namespace = dict(__name__='namedtuple_%s' % typename)
|
|
try:
|
|
exec(class_definition, namespace)
|
|
except SyntaxError as e:
|
|
raise SyntaxError(e.msg + ':\n\n' + class_definition)
|
|
result = namespace[typename]
|
|
result._source = class_definition
|
|
if verbose:
|
|
print(result._source)
|
|
|
|
# For pickling to work, the __module__ variable needs to be set to the frame
|
|
# where the named tuple is created. Bypass this step in enviroments where
|
|
# sys._getframe is not defined (Jython for example) or sys._getframe is not
|
|
# defined for arguments greater than 0 (IronPython).
|
|
try:
|
|
result.__module__ = _sys._getframe(1).f_globals.get('__name__', '__main__')
|
|
except (AttributeError, ValueError):
|
|
pass
|
|
|
|
return result
|
|
|
|
|
|
########################################################################
|
|
### Counter
|
|
########################################################################
|
|
|
|
def _count_elements(mapping, iterable):
|
|
'Tally elements from the iterable.'
|
|
mapping_get = mapping.get
|
|
for elem in iterable:
|
|
mapping[elem] = mapping_get(elem, 0) + 1
|
|
|
|
try: # Load C helper function if available
|
|
from _collections import _count_elements
|
|
except ImportError:
|
|
pass
|
|
|
|
class Counter(dict):
|
|
'''Dict subclass for counting hashable items. Sometimes called a bag
|
|
or multiset. Elements are stored as dictionary keys and their counts
|
|
are stored as dictionary values.
|
|
|
|
>>> c = Counter('abcdeabcdabcaba') # count elements from a string
|
|
|
|
>>> c.most_common(3) # three most common elements
|
|
[('a', 5), ('b', 4), ('c', 3)]
|
|
>>> sorted(c) # list all unique elements
|
|
['a', 'b', 'c', 'd', 'e']
|
|
>>> ''.join(sorted(c.elements())) # list elements with repetitions
|
|
'aaaaabbbbcccdde'
|
|
>>> sum(c.values()) # total of all counts
|
|
15
|
|
|
|
>>> c['a'] # count of letter 'a'
|
|
5
|
|
>>> for elem in 'shazam': # update counts from an iterable
|
|
... c[elem] += 1 # by adding 1 to each element's count
|
|
>>> c['a'] # now there are seven 'a'
|
|
7
|
|
>>> del c['b'] # remove all 'b'
|
|
>>> c['b'] # now there are zero 'b'
|
|
0
|
|
|
|
>>> d = Counter('simsalabim') # make another counter
|
|
>>> c.update(d) # add in the second counter
|
|
>>> c['a'] # now there are nine 'a'
|
|
9
|
|
|
|
>>> c.clear() # empty the counter
|
|
>>> c
|
|
Counter()
|
|
|
|
Note: If a count is set to zero or reduced to zero, it will remain
|
|
in the counter until the entry is deleted or the counter is cleared:
|
|
|
|
>>> c = Counter('aaabbc')
|
|
>>> c['b'] -= 2 # reduce the count of 'b' by two
|
|
>>> c.most_common() # 'b' is still in, but its count is zero
|
|
[('a', 3), ('c', 1), ('b', 0)]
|
|
|
|
'''
|
|
# References:
|
|
# http://en.wikipedia.org/wiki/Multiset
|
|
# http://www.gnu.org/software/smalltalk/manual-base/html_node/Bag.html
|
|
# http://www.demo2s.com/Tutorial/Cpp/0380__set-multiset/Catalog0380__set-multiset.htm
|
|
# http://code.activestate.com/recipes/259174/
|
|
# Knuth, TAOCP Vol. II section 4.6.3
|
|
|
|
def __init__(self, iterable=None, **kwds):
|
|
'''Create a new, empty Counter object. And if given, count elements
|
|
from an input iterable. Or, initialize the count from another mapping
|
|
of elements to their counts.
|
|
|
|
>>> c = Counter() # a new, empty counter
|
|
>>> c = Counter('gallahad') # a new counter from an iterable
|
|
>>> c = Counter({'a': 4, 'b': 2}) # a new counter from a mapping
|
|
>>> c = Counter(a=4, b=2) # a new counter from keyword args
|
|
|
|
'''
|
|
super().__init__()
|
|
self.update(iterable, **kwds)
|
|
|
|
def __missing__(self, key):
|
|
'The count of elements not in the Counter is zero.'
|
|
# Needed so that self[missing_item] does not raise KeyError
|
|
return 0
|
|
|
|
def most_common(self, n=None):
|
|
'''List the n most common elements and their counts from the most
|
|
common to the least. If n is None, then list all element counts.
|
|
|
|
>>> Counter('abcdeabcdabcaba').most_common(3)
|
|
[('a', 5), ('b', 4), ('c', 3)]
|
|
|
|
'''
|
|
# Emulate Bag.sortedByCount from Smalltalk
|
|
if n is None:
|
|
return sorted(self.items(), key=_itemgetter(1), reverse=True)
|
|
return _heapq.nlargest(n, self.items(), key=_itemgetter(1))
|
|
|
|
def elements(self):
|
|
'''Iterator over elements repeating each as many times as its count.
|
|
|
|
>>> c = Counter('ABCABC')
|
|
>>> sorted(c.elements())
|
|
['A', 'A', 'B', 'B', 'C', 'C']
|
|
|
|
# Knuth's example for prime factors of 1836: 2**2 * 3**3 * 17**1
|
|
>>> prime_factors = Counter({2: 2, 3: 3, 17: 1})
|
|
>>> product = 1
|
|
>>> for factor in prime_factors.elements(): # loop over factors
|
|
... product *= factor # and multiply them
|
|
>>> product
|
|
1836
|
|
|
|
Note, if an element's count has been set to zero or is a negative
|
|
number, elements() will ignore it.
|
|
|
|
'''
|
|
# Emulate Bag.do from Smalltalk and Multiset.begin from C++.
|
|
return _chain.from_iterable(_starmap(_repeat, self.items()))
|
|
|
|
# Override dict methods where necessary
|
|
|
|
@classmethod
|
|
def fromkeys(cls, iterable, v=None):
|
|
# There is no equivalent method for counters because setting v=1
|
|
# means that no element can have a count greater than one.
|
|
raise NotImplementedError(
|
|
'Counter.fromkeys() is undefined. Use Counter(iterable) instead.')
|
|
|
|
def update(self, iterable=None, **kwds):
|
|
'''Like dict.update() but add counts instead of replacing them.
|
|
|
|
Source can be an iterable, a dictionary, or another Counter instance.
|
|
|
|
>>> c = Counter('which')
|
|
>>> c.update('witch') # add elements from another iterable
|
|
>>> d = Counter('watch')
|
|
>>> c.update(d) # add elements from another counter
|
|
>>> c['h'] # four 'h' in which, witch, and watch
|
|
4
|
|
|
|
'''
|
|
# The regular dict.update() operation makes no sense here because the
|
|
# replace behavior results in the some of original untouched counts
|
|
# being mixed-in with all of the other counts for a mismash that
|
|
# doesn't have a straight-forward interpretation in most counting
|
|
# contexts. Instead, we implement straight-addition. Both the inputs
|
|
# and outputs are allowed to contain zero and negative counts.
|
|
|
|
if iterable is not None:
|
|
if isinstance(iterable, Mapping):
|
|
if self:
|
|
self_get = self.get
|
|
for elem, count in iterable.items():
|
|
self[elem] = count + self_get(elem, 0)
|
|
else:
|
|
super().update(iterable) # fast path when counter is empty
|
|
else:
|
|
_count_elements(self, iterable)
|
|
if kwds:
|
|
self.update(kwds)
|
|
|
|
def subtract(self, iterable=None, **kwds):
|
|
'''Like dict.update() but subtracts counts instead of replacing them.
|
|
Counts can be reduced below zero. Both the inputs and outputs are
|
|
allowed to contain zero and negative counts.
|
|
|
|
Source can be an iterable, a dictionary, or another Counter instance.
|
|
|
|
>>> c = Counter('which')
|
|
>>> c.subtract('witch') # subtract elements from another iterable
|
|
>>> c.subtract(Counter('watch')) # subtract elements from another counter
|
|
>>> c['h'] # 2 in which, minus 1 in witch, minus 1 in watch
|
|
0
|
|
>>> c['w'] # 1 in which, minus 1 in witch, minus 1 in watch
|
|
-1
|
|
|
|
'''
|
|
if iterable is not None:
|
|
self_get = self.get
|
|
if isinstance(iterable, Mapping):
|
|
for elem, count in iterable.items():
|
|
self[elem] = self_get(elem, 0) - count
|
|
else:
|
|
for elem in iterable:
|
|
self[elem] = self_get(elem, 0) - 1
|
|
if kwds:
|
|
self.subtract(kwds)
|
|
|
|
def copy(self):
|
|
'Return a shallow copy.'
|
|
return self.__class__(self)
|
|
|
|
def __reduce__(self):
|
|
return self.__class__, (dict(self),)
|
|
|
|
def __delitem__(self, elem):
|
|
'Like dict.__delitem__() but does not raise KeyError for missing values.'
|
|
if elem in self:
|
|
super().__delitem__(elem)
|
|
|
|
def __repr__(self):
|
|
if not self:
|
|
return '%s()' % self.__class__.__name__
|
|
items = ', '.join(map('%r: %r'.__mod__, self.most_common()))
|
|
return '%s({%s})' % (self.__class__.__name__, items)
|
|
|
|
# Multiset-style mathematical operations discussed in:
|
|
# Knuth TAOCP Volume II section 4.6.3 exercise 19
|
|
# and at http://en.wikipedia.org/wiki/Multiset
|
|
#
|
|
# Outputs guaranteed to only include positive counts.
|
|
#
|
|
# To strip negative and zero counts, add-in an empty counter:
|
|
# c += Counter()
|
|
|
|
def __add__(self, other):
|
|
'''Add counts from two counters.
|
|
|
|
>>> Counter('abbb') + Counter('bcc')
|
|
Counter({'b': 4, 'c': 2, 'a': 1})
|
|
|
|
'''
|
|
if not isinstance(other, Counter):
|
|
return NotImplemented
|
|
result = Counter()
|
|
for elem, count in self.items():
|
|
newcount = count + other[elem]
|
|
if newcount > 0:
|
|
result[elem] = newcount
|
|
for elem, count in other.items():
|
|
if elem not in self and count > 0:
|
|
result[elem] = count
|
|
return result
|
|
|
|
def __sub__(self, other):
|
|
''' Subtract count, but keep only results with positive counts.
|
|
|
|
>>> Counter('abbbc') - Counter('bccd')
|
|
Counter({'b': 2, 'a': 1})
|
|
|
|
'''
|
|
if not isinstance(other, Counter):
|
|
return NotImplemented
|
|
result = Counter()
|
|
for elem, count in self.items():
|
|
newcount = count - other[elem]
|
|
if newcount > 0:
|
|
result[elem] = newcount
|
|
for elem, count in other.items():
|
|
if elem not in self and count < 0:
|
|
result[elem] = 0 - count
|
|
return result
|
|
|
|
def __or__(self, other):
|
|
'''Union is the maximum of value in either of the input counters.
|
|
|
|
>>> Counter('abbb') | Counter('bcc')
|
|
Counter({'b': 3, 'c': 2, 'a': 1})
|
|
|
|
'''
|
|
if not isinstance(other, Counter):
|
|
return NotImplemented
|
|
result = Counter()
|
|
for elem, count in self.items():
|
|
other_count = other[elem]
|
|
newcount = other_count if count < other_count else count
|
|
if newcount > 0:
|
|
result[elem] = newcount
|
|
for elem, count in other.items():
|
|
if elem not in self and count > 0:
|
|
result[elem] = count
|
|
return result
|
|
|
|
def __and__(self, other):
|
|
''' Intersection is the minimum of corresponding counts.
|
|
|
|
>>> Counter('abbb') & Counter('bcc')
|
|
Counter({'b': 1})
|
|
|
|
'''
|
|
if not isinstance(other, Counter):
|
|
return NotImplemented
|
|
result = Counter()
|
|
for elem, count in self.items():
|
|
other_count = other[elem]
|
|
newcount = count if count < other_count else other_count
|
|
if newcount > 0:
|
|
result[elem] = newcount
|
|
return result
|
|
|
|
def __pos__(self):
|
|
'Adds an empty counter, effectively stripping negative and zero counts'
|
|
return self + Counter()
|
|
|
|
def __neg__(self):
|
|
'''Subtracts from an empty counter. Strips positive and zero counts,
|
|
and flips the sign on negative counts.
|
|
|
|
'''
|
|
return Counter() - self
|
|
|
|
|
|
########################################################################
|
|
### ChainMap (helper for configparser and string.Template)
|
|
########################################################################
|
|
|
|
class ChainMap(MutableMapping):
|
|
''' A ChainMap groups multiple dicts (or other mappings) together
|
|
to create a single, updateable view.
|
|
|
|
The underlying mappings are stored in a list. That list is public and can
|
|
accessed or updated using the *maps* attribute. There is no other state.
|
|
|
|
Lookups search the underlying mappings successively until a key is found.
|
|
In contrast, writes, updates, and deletions only operate on the first
|
|
mapping.
|
|
|
|
'''
|
|
|
|
def __init__(self, *maps):
|
|
'''Initialize a ChainMap by setting *maps* to the given mappings.
|
|
If no mappings are provided, a single empty dictionary is used.
|
|
|
|
'''
|
|
self.maps = list(maps) or [{}] # always at least one map
|
|
|
|
def __missing__(self, key):
|
|
raise KeyError(key)
|
|
|
|
def __getitem__(self, key):
|
|
for mapping in self.maps:
|
|
try:
|
|
return mapping[key] # can't use 'key in mapping' with defaultdict
|
|
except KeyError:
|
|
pass
|
|
return self.__missing__(key) # support subclasses that define __missing__
|
|
|
|
def get(self, key, default=None):
|
|
return self[key] if key in self else default
|
|
|
|
def __len__(self):
|
|
return len(set().union(*self.maps)) # reuses stored hash values if possible
|
|
|
|
def __iter__(self):
|
|
return iter(set().union(*self.maps))
|
|
|
|
def __contains__(self, key):
|
|
return any(key in m for m in self.maps)
|
|
|
|
def __bool__(self):
|
|
return any(self.maps)
|
|
|
|
@_recursive_repr()
|
|
def __repr__(self):
|
|
return '{0.__class__.__name__}({1})'.format(
|
|
self, ', '.join(map(repr, self.maps)))
|
|
|
|
@classmethod
|
|
def fromkeys(cls, iterable, *args):
|
|
'Create a ChainMap with a single dict created from the iterable.'
|
|
return cls(dict.fromkeys(iterable, *args))
|
|
|
|
def copy(self):
|
|
'New ChainMap or subclass with a new copy of maps[0] and refs to maps[1:]'
|
|
return self.__class__(self.maps[0].copy(), *self.maps[1:])
|
|
|
|
__copy__ = copy
|
|
|
|
def new_child(self): # like Django's Context.push()
|
|
'New ChainMap with a new dict followed by all previous maps.'
|
|
return self.__class__({}, *self.maps)
|
|
|
|
@property
|
|
def parents(self): # like Django's Context.pop()
|
|
'New ChainMap from maps[1:].'
|
|
return self.__class__(*self.maps[1:])
|
|
|
|
def __setitem__(self, key, value):
|
|
self.maps[0][key] = value
|
|
|
|
def __delitem__(self, key):
|
|
try:
|
|
del self.maps[0][key]
|
|
except KeyError:
|
|
raise KeyError('Key not found in the first mapping: {!r}'.format(key))
|
|
|
|
def popitem(self):
|
|
'Remove and return an item pair from maps[0]. Raise KeyError is maps[0] is empty.'
|
|
try:
|
|
return self.maps[0].popitem()
|
|
except KeyError:
|
|
raise KeyError('No keys found in the first mapping.')
|
|
|
|
def pop(self, key, *args):
|
|
'Remove *key* from maps[0] and return its value. Raise KeyError if *key* not in maps[0].'
|
|
try:
|
|
return self.maps[0].pop(key, *args)
|
|
except KeyError:
|
|
raise KeyError('Key not found in the first mapping: {!r}'.format(key))
|
|
|
|
def clear(self):
|
|
'Clear maps[0], leaving maps[1:] intact.'
|
|
self.maps[0].clear()
|
|
|
|
|
|
################################################################################
|
|
### UserDict
|
|
################################################################################
|
|
|
|
class UserDict(MutableMapping):
|
|
|
|
# Start by filling-out the abstract methods
|
|
def __init__(self, dict=None, **kwargs):
|
|
self.data = {}
|
|
if dict is not None:
|
|
self.update(dict)
|
|
if len(kwargs):
|
|
self.update(kwargs)
|
|
def __len__(self): return len(self.data)
|
|
def __getitem__(self, key):
|
|
if key in self.data:
|
|
return self.data[key]
|
|
if hasattr(self.__class__, "__missing__"):
|
|
return self.__class__.__missing__(self, key)
|
|
raise KeyError(key)
|
|
def __setitem__(self, key, item): self.data[key] = item
|
|
def __delitem__(self, key): del self.data[key]
|
|
def __iter__(self):
|
|
return iter(self.data)
|
|
|
|
# Modify __contains__ to work correctly when __missing__ is present
|
|
def __contains__(self, key):
|
|
return key in self.data
|
|
|
|
# Now, add the methods in dicts but not in MutableMapping
|
|
def __repr__(self): return repr(self.data)
|
|
def copy(self):
|
|
if self.__class__ is UserDict:
|
|
return UserDict(self.data.copy())
|
|
import copy
|
|
data = self.data
|
|
try:
|
|
self.data = {}
|
|
c = copy.copy(self)
|
|
finally:
|
|
self.data = data
|
|
c.update(self)
|
|
return c
|
|
@classmethod
|
|
def fromkeys(cls, iterable, value=None):
|
|
d = cls()
|
|
for key in iterable:
|
|
d[key] = value
|
|
return d
|
|
|
|
|
|
|
|
################################################################################
|
|
### UserList
|
|
################################################################################
|
|
|
|
class UserList(MutableSequence):
|
|
"""A more or less complete user-defined wrapper around list objects."""
|
|
def __init__(self, initlist=None):
|
|
self.data = []
|
|
if initlist is not None:
|
|
# XXX should this accept an arbitrary sequence?
|
|
if type(initlist) == type(self.data):
|
|
self.data[:] = initlist
|
|
elif isinstance(initlist, UserList):
|
|
self.data[:] = initlist.data[:]
|
|
else:
|
|
self.data = list(initlist)
|
|
def __repr__(self): return repr(self.data)
|
|
def __lt__(self, other): return self.data < self.__cast(other)
|
|
def __le__(self, other): return self.data <= self.__cast(other)
|
|
def __eq__(self, other): return self.data == self.__cast(other)
|
|
def __ne__(self, other): return self.data != self.__cast(other)
|
|
def __gt__(self, other): return self.data > self.__cast(other)
|
|
def __ge__(self, other): return self.data >= self.__cast(other)
|
|
def __cast(self, other):
|
|
return other.data if isinstance(other, UserList) else other
|
|
def __contains__(self, item): return item in self.data
|
|
def __len__(self): return len(self.data)
|
|
def __getitem__(self, i): return self.data[i]
|
|
def __setitem__(self, i, item): self.data[i] = item
|
|
def __delitem__(self, i): del self.data[i]
|
|
def __add__(self, other):
|
|
if isinstance(other, UserList):
|
|
return self.__class__(self.data + other.data)
|
|
elif isinstance(other, type(self.data)):
|
|
return self.__class__(self.data + other)
|
|
return self.__class__(self.data + list(other))
|
|
def __radd__(self, other):
|
|
if isinstance(other, UserList):
|
|
return self.__class__(other.data + self.data)
|
|
elif isinstance(other, type(self.data)):
|
|
return self.__class__(other + self.data)
|
|
return self.__class__(list(other) + self.data)
|
|
def __iadd__(self, other):
|
|
if isinstance(other, UserList):
|
|
self.data += other.data
|
|
elif isinstance(other, type(self.data)):
|
|
self.data += other
|
|
else:
|
|
self.data += list(other)
|
|
return self
|
|
def __mul__(self, n):
|
|
return self.__class__(self.data*n)
|
|
__rmul__ = __mul__
|
|
def __imul__(self, n):
|
|
self.data *= n
|
|
return self
|
|
def append(self, item): self.data.append(item)
|
|
def insert(self, i, item): self.data.insert(i, item)
|
|
def pop(self, i=-1): return self.data.pop(i)
|
|
def remove(self, item): self.data.remove(item)
|
|
def clear(self): self.data.clear()
|
|
def copy(self): return self.__class__(self)
|
|
def count(self, item): return self.data.count(item)
|
|
def index(self, item, *args): return self.data.index(item, *args)
|
|
def reverse(self): self.data.reverse()
|
|
def sort(self, *args, **kwds): self.data.sort(*args, **kwds)
|
|
def extend(self, other):
|
|
if isinstance(other, UserList):
|
|
self.data.extend(other.data)
|
|
else:
|
|
self.data.extend(other)
|
|
|
|
|
|
|
|
################################################################################
|
|
### UserString
|
|
################################################################################
|
|
|
|
class UserString(Sequence):
|
|
def __init__(self, seq):
|
|
if isinstance(seq, str):
|
|
self.data = seq
|
|
elif isinstance(seq, UserString):
|
|
self.data = seq.data[:]
|
|
else:
|
|
self.data = str(seq)
|
|
def __str__(self): return str(self.data)
|
|
def __repr__(self): return repr(self.data)
|
|
def __int__(self): return int(self.data)
|
|
def __float__(self): return float(self.data)
|
|
def __complex__(self): return complex(self.data)
|
|
def __hash__(self): return hash(self.data)
|
|
|
|
def __eq__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data == string.data
|
|
return self.data == string
|
|
def __ne__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data != string.data
|
|
return self.data != string
|
|
def __lt__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data < string.data
|
|
return self.data < string
|
|
def __le__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data <= string.data
|
|
return self.data <= string
|
|
def __gt__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data > string.data
|
|
return self.data > string
|
|
def __ge__(self, string):
|
|
if isinstance(string, UserString):
|
|
return self.data >= string.data
|
|
return self.data >= string
|
|
|
|
def __contains__(self, char):
|
|
if isinstance(char, UserString):
|
|
char = char.data
|
|
return char in self.data
|
|
|
|
def __len__(self): return len(self.data)
|
|
def __getitem__(self, index): return self.__class__(self.data[index])
|
|
def __add__(self, other):
|
|
if isinstance(other, UserString):
|
|
return self.__class__(self.data + other.data)
|
|
elif isinstance(other, str):
|
|
return self.__class__(self.data + other)
|
|
return self.__class__(self.data + str(other))
|
|
def __radd__(self, other):
|
|
if isinstance(other, str):
|
|
return self.__class__(other + self.data)
|
|
return self.__class__(str(other) + self.data)
|
|
def __mul__(self, n):
|
|
return self.__class__(self.data*n)
|
|
__rmul__ = __mul__
|
|
def __mod__(self, args):
|
|
return self.__class__(self.data % args)
|
|
|
|
# the following methods are defined in alphabetical order:
|
|
def capitalize(self): return self.__class__(self.data.capitalize())
|
|
def center(self, width, *args):
|
|
return self.__class__(self.data.center(width, *args))
|
|
def count(self, sub, start=0, end=_sys.maxsize):
|
|
if isinstance(sub, UserString):
|
|
sub = sub.data
|
|
return self.data.count(sub, start, end)
|
|
def encode(self, encoding=None, errors=None): # XXX improve this?
|
|
if encoding:
|
|
if errors:
|
|
return self.__class__(self.data.encode(encoding, errors))
|
|
return self.__class__(self.data.encode(encoding))
|
|
return self.__class__(self.data.encode())
|
|
def endswith(self, suffix, start=0, end=_sys.maxsize):
|
|
return self.data.endswith(suffix, start, end)
|
|
def expandtabs(self, tabsize=8):
|
|
return self.__class__(self.data.expandtabs(tabsize))
|
|
def find(self, sub, start=0, end=_sys.maxsize):
|
|
if isinstance(sub, UserString):
|
|
sub = sub.data
|
|
return self.data.find(sub, start, end)
|
|
def format(self, *args, **kwds):
|
|
return self.data.format(*args, **kwds)
|
|
def index(self, sub, start=0, end=_sys.maxsize):
|
|
return self.data.index(sub, start, end)
|
|
def isalpha(self): return self.data.isalpha()
|
|
def isalnum(self): return self.data.isalnum()
|
|
def isdecimal(self): return self.data.isdecimal()
|
|
def isdigit(self): return self.data.isdigit()
|
|
def isidentifier(self): return self.data.isidentifier()
|
|
def islower(self): return self.data.islower()
|
|
def isnumeric(self): return self.data.isnumeric()
|
|
def isspace(self): return self.data.isspace()
|
|
def istitle(self): return self.data.istitle()
|
|
def isupper(self): return self.data.isupper()
|
|
def join(self, seq): return self.data.join(seq)
|
|
def ljust(self, width, *args):
|
|
return self.__class__(self.data.ljust(width, *args))
|
|
def lower(self): return self.__class__(self.data.lower())
|
|
def lstrip(self, chars=None): return self.__class__(self.data.lstrip(chars))
|
|
def partition(self, sep):
|
|
return self.data.partition(sep)
|
|
def replace(self, old, new, maxsplit=-1):
|
|
if isinstance(old, UserString):
|
|
old = old.data
|
|
if isinstance(new, UserString):
|
|
new = new.data
|
|
return self.__class__(self.data.replace(old, new, maxsplit))
|
|
def rfind(self, sub, start=0, end=_sys.maxsize):
|
|
if isinstance(sub, UserString):
|
|
sub = sub.data
|
|
return self.data.rfind(sub, start, end)
|
|
def rindex(self, sub, start=0, end=_sys.maxsize):
|
|
return self.data.rindex(sub, start, end)
|
|
def rjust(self, width, *args):
|
|
return self.__class__(self.data.rjust(width, *args))
|
|
def rpartition(self, sep):
|
|
return self.data.rpartition(sep)
|
|
def rstrip(self, chars=None):
|
|
return self.__class__(self.data.rstrip(chars))
|
|
def split(self, sep=None, maxsplit=-1):
|
|
return self.data.split(sep, maxsplit)
|
|
def rsplit(self, sep=None, maxsplit=-1):
|
|
return self.data.rsplit(sep, maxsplit)
|
|
def splitlines(self, keepends=0): return self.data.splitlines(keepends)
|
|
def startswith(self, prefix, start=0, end=_sys.maxsize):
|
|
return self.data.startswith(prefix, start, end)
|
|
def strip(self, chars=None): return self.__class__(self.data.strip(chars))
|
|
def swapcase(self): return self.__class__(self.data.swapcase())
|
|
def title(self): return self.__class__(self.data.title())
|
|
def translate(self, *args):
|
|
return self.__class__(self.data.translate(*args))
|
|
def upper(self): return self.__class__(self.data.upper())
|
|
def zfill(self, width): return self.__class__(self.data.zfill(width))
|
|
|
|
|
|
|
|
################################################################################
|
|
### Simple tests
|
|
################################################################################
|
|
|
|
if __name__ == '__main__':
|
|
# verify that instances can be pickled
|
|
from pickle import loads, dumps
|
|
Point = namedtuple('Point', 'x, y', True)
|
|
p = Point(x=10, y=20)
|
|
assert p == loads(dumps(p))
|
|
|
|
# test and demonstrate ability to override methods
|
|
class Point(namedtuple('Point', 'x y')):
|
|
__slots__ = ()
|
|
@property
|
|
def hypot(self):
|
|
return (self.x ** 2 + self.y ** 2) ** 0.5
|
|
def __str__(self):
|
|
return 'Point: x=%6.3f y=%6.3f hypot=%6.3f' % (self.x, self.y, self.hypot)
|
|
|
|
for p in Point(3, 4), Point(14, 5/7.):
|
|
print (p)
|
|
|
|
class Point(namedtuple('Point', 'x y')):
|
|
'Point class with optimized _make() and _replace() without error-checking'
|
|
__slots__ = ()
|
|
_make = classmethod(tuple.__new__)
|
|
def _replace(self, _map=map, **kwds):
|
|
return self._make(_map(kwds.get, ('x', 'y'), self))
|
|
|
|
print(Point(11, 22)._replace(x=100))
|
|
|
|
Point3D = namedtuple('Point3D', Point._fields + ('z',))
|
|
print(Point3D.__doc__)
|
|
|
|
import doctest
|
|
TestResults = namedtuple('TestResults', 'failed attempted')
|
|
print(TestResults(*doctest.testmod()))
|