| 1 | # Copyright (c) 2009 Raymond Hettinger |
| 2 | # |
| 3 | # SPDX-License-Identifier: MIT |
| 4 | |
| 5 | from UserDict import DictMixin |
| 6 | |
| 7 | |
| 8 | class OrderedDict(dict, DictMixin): |
| 9 | |
| 10 | def __init__(self, *args, **kwds): |
| 11 | if len(args) > 1: |
| 12 | raise TypeError('expected at most 1 arguments, got %d' % len(args)) |
| 13 | try: |
| 14 | self.__end |
| 15 | except AttributeError: |
| 16 | self.clear() |
| 17 | self.update(*args, **kwds) |
| 18 | |
| 19 | def clear(self): |
| 20 | self.__end = end = [] |
| 21 | end += [None, end, end] # sentinel node for doubly linked list |
| 22 | self.__map = {} # key --> [key, prev, next] |
| 23 | dict.clear(self) |
| 24 | |
| 25 | def __setitem__(self, key, value): |
| 26 | if key not in self: |
| 27 | end = self.__end |
| 28 | curr = end[1] |
| 29 | curr[2] = end[1] = self.__map[key] = [key, curr, end] |
| 30 | dict.__setitem__(self, key, value) |
| 31 | |
| 32 | def __delitem__(self, key): |
| 33 | dict.__delitem__(self, key) |
| 34 | key, prev, next = self.__map.pop(key) |
| 35 | prev[2] = next |
| 36 | next[1] = prev |
| 37 | |
| 38 | def __iter__(self): |
| 39 | end = self.__end |
| 40 | curr = end[2] |
| 41 | while curr is not end: |
| 42 | yield curr[0] |
| 43 | curr = curr[2] |
| 44 | |
| 45 | def __reversed__(self): |
| 46 | end = self.__end |
| 47 | curr = end[1] |
| 48 | while curr is not end: |
| 49 | yield curr[0] |
| 50 | curr = curr[1] |
| 51 | |
| 52 | def popitem(self, last=True): |
| 53 | if not self: |
| 54 | raise KeyError('dictionary is empty') |
| 55 | if last: |
| 56 | key = reversed(self).next() |
| 57 | else: |
| 58 | key = iter(self).next() |
| 59 | value = self.pop(key) |
| 60 | return key, value |
| 61 | |
| 62 | def __reduce__(self): |
| 63 | items = [[k, self[k]] for k in self] |
| 64 | tmp = self.__map, self.__end |
| 65 | del self.__map, self.__end |
| 66 | inst_dict = vars(self).copy() |
| 67 | self.__map, self.__end = tmp |
| 68 | if inst_dict: |
| 69 | return self.__class__, (items,), inst_dict |
| 70 | return self.__class__, (items,) |
| 71 | |
| 72 | def keys(self): |
| 73 | return list(self) |
| 74 | |
| 75 | setdefault = DictMixin.setdefault |
| 76 | update = DictMixin.update |
| 77 | pop = DictMixin.pop |
| 78 | values = DictMixin.values |
| 79 | items = DictMixin.items |
| 80 | iterkeys = DictMixin.iterkeys |
| 81 | itervalues = DictMixin.itervalues |
| 82 | iteritems = DictMixin.iteritems |
| 83 | |
| 84 | def __repr__(self): |
| 85 | if not self: |
| 86 | return '%s()' % (self.__class__.__name__,) |
| 87 | return '%s(%r)' % (self.__class__.__name__, self.items()) |
| 88 | |
| 89 | def copy(self): |
| 90 | return self.__class__(self) |
| 91 | |
| 92 | @classmethod |
| 93 | def fromkeys(cls, iterable, value=None): |
| 94 | d = cls() |
| 95 | for key in iterable: |
| 96 | d[key] = value |
| 97 | return d |
| 98 | |
| 99 | def __eq__(self, other): |
| 100 | if isinstance(other, OrderedDict): |
| 101 | if len(self) != len(other): |
| 102 | return False |
| 103 | for p, q in zip(self.items(), other.items()): |
| 104 | if p != q: |
| 105 | return False |
| 106 | return True |
| 107 | return dict.__eq__(self, other) |
| 108 | |
| 109 | def __ne__(self, other): |
| 110 | return not self == other |