ordereddict.py 3.0 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110
  1. # Copyright (c) 2009 Raymond Hettinger
  2. #
  3. # SPDX-License-Identifier: MIT
  4. from UserDict import DictMixin
  5. class OrderedDict(dict, DictMixin):
  6. def __init__(self, *args, **kwds):
  7. if len(args) > 1:
  8. raise TypeError('expected at most 1 arguments, got %d' % len(args))
  9. try:
  10. self.__end
  11. except AttributeError:
  12. self.clear()
  13. self.update(*args, **kwds)
  14. def clear(self):
  15. self.__end = end = []
  16. end += [None, end, end] # sentinel node for doubly linked list
  17. self.__map = {} # key --> [key, prev, next]
  18. dict.clear(self)
  19. def __setitem__(self, key, value):
  20. if key not in self:
  21. end = self.__end
  22. curr = end[1]
  23. curr[2] = end[1] = self.__map[key] = [key, curr, end]
  24. dict.__setitem__(self, key, value)
  25. def __delitem__(self, key):
  26. dict.__delitem__(self, key)
  27. key, prev, next = self.__map.pop(key)
  28. prev[2] = next
  29. next[1] = prev
  30. def __iter__(self):
  31. end = self.__end
  32. curr = end[2]
  33. while curr is not end:
  34. yield curr[0]
  35. curr = curr[2]
  36. def __reversed__(self):
  37. end = self.__end
  38. curr = end[1]
  39. while curr is not end:
  40. yield curr[0]
  41. curr = curr[1]
  42. def popitem(self, last=True):
  43. if not self:
  44. raise KeyError('dictionary is empty')
  45. if last:
  46. key = reversed(self).next()
  47. else:
  48. key = iter(self).next()
  49. value = self.pop(key)
  50. return key, value
  51. def __reduce__(self):
  52. items = [[k, self[k]] for k in self]
  53. tmp = self.__map, self.__end
  54. del self.__map, self.__end
  55. inst_dict = vars(self).copy()
  56. self.__map, self.__end = tmp
  57. if inst_dict:
  58. return self.__class__, (items,), inst_dict
  59. return self.__class__, (items,)
  60. def keys(self):
  61. return list(self)
  62. setdefault = DictMixin.setdefault
  63. update = DictMixin.update
  64. pop = DictMixin.pop
  65. values = DictMixin.values
  66. items = DictMixin.items
  67. iterkeys = DictMixin.iterkeys
  68. itervalues = DictMixin.itervalues
  69. iteritems = DictMixin.iteritems
  70. def __repr__(self):
  71. if not self:
  72. return '%s()' % (self.__class__.__name__,)
  73. return '%s(%r)' % (self.__class__.__name__, self.items())
  74. def copy(self):
  75. return self.__class__(self)
  76. @classmethod
  77. def fromkeys(cls, iterable, value=None):
  78. d = cls()
  79. for key in iterable:
  80. d[key] = value
  81. return d
  82. def __eq__(self, other):
  83. if isinstance(other, OrderedDict):
  84. if len(self) != len(other):
  85. return False
  86. for p, q in zip(self.items(), other.items()):
  87. if p != q:
  88. return False
  89. return True
  90. return dict.__eq__(self, other)
  91. def __ne__(self, other):
  92. return not self == other