src/mjacob/collections/FrozenIndex.py

   1 # This Python file uses the following encoding: utf-8
   2 '''
   3 Created on Jun 2, 2011
   4
   5 @author: mjacob
   6 '''
   7 from itertools import chain
   8
   9 class FrozenIndex(object):
  10     """immutable collection of objects "indexed" by other objects"""
  11
  12     EMPTY = frozenset()
  13
  14     def __init__(self, items):
  15         d = {}
  16         for k,v in items:
  17             if k in d:
  18                 d[k].append(v)
  19             else:
  20                 d[k] = [v]
  21         for k in d:
  22             d[k] = frozenset(d[k])
  23         self.__dict = d
  24         self.__values = frozenset(list(self.values()))
  25         self.__hash = hash(tuple(items))
  26
  27     def __contains__(self, k):
  28         return k in self.__values
  29
  30     def __getitem__(self, k):
  31         if k in self.__dict:
  32             return self.__dict[k]
  33         else:
  34             return FrozenIndex.EMPTY
  35
  36     def __iter__(self):
  37         return iter(self.values())
  38
  39     def __len__(self):
  40         return len(list(self.values()))
  41
  42     def get(self, k):
  43         if k in self.__dict:
  44             return self.__dict.get(k)
  45         else:
  46             return FrozenIndex.EMPTY
  47
  48     def has_key(self, k):
  49         return k in self.__dict
  50
  51     def items(self):
  52         return tuple(((k,v) for k in self.__dict for v in self.__dict[k]))
  53
  54     def iteritems(self):
  55         return (((k,v) for k in self.__dict for v in self.__dict[k]))
  56
  57     def iterkeys(self):
  58         return iter(self.__dict.keys())
  59
  60     def itervalues(self):
  61         return chain(*list(self.__dict.values()))
  62
  63     def keys(self):
  64         return list(self.__dict.keys())
  65
  66     def values(self):
  67         return tuple(chain(*list(self.__dict.values())))
  68
  69     def hash(self):
  70         return self.__hash
  71
  72     def __eq__(self, othr):
  73         return self.__dict == othr.__dict
  74
  75     def __ge__(self, othr):
  76         return self.__dict >= othr.__dict
  77
  78     def __gt__(self, othr):
  79         return self.__dict > othr.__dict
  80
  81     def __le__(self, othr):
  82         return self.__dict <= othr.__dict
  83
  84     def __lt__(self, othr):
  85         return self.__dict < othr.__dict
  86
  87     def __ne__(self, othr):
  88         return self.__dict != othr.__dict
  89
  90     def __sizeof__(self):
  91         return self.__dict.__sizeof__()
  92
  93     def __repr__(self):
  94         return repr(self.__dict)
  95
  96     def __str__(self):
  97         return str(self.__dict)