Source Code for Module lxml.html._dictmixin

  1  """ 
  2  A backport of UserDict.DictMixin for pre-python-2.4 
  3  """ 
  4  __all__ = ['DictMixin'] 
  5   
  6  try: 
  7      from UserDict import DictMixin 
  8  except ImportError: 
  9 -    class DictMixin: 
 10          # Mixin defining all dictionary methods for classes that already have 
 11          # a minimum dictionary interface including getitem, setitem, delitem, 
 12          # and keys. Without knowledge of the subclass constructor, the mixin 
 13          # does not define __init__() or copy().  In addition to the four base 
 14          # methods, progressively more efficiency comes with defining 
 15          # __contains__(), __iter__(), and iteritems(). 
 16   
 17          # second level definitions support higher levels 
 18 -        def __iter__(self): 
 19              for k in self.keys(): 
 20                  yield k 
 21 -        def has_key(self, key): 
 22              try: 
 23                  value = self[key] 
 24              except KeyError: 
 25                  return False 
 26              return True 
 27 -        def __contains__(self, key): 
 28              return self.has_key(key) 
 29   
 30          # third level takes advantage of second level definitions 
 31 -        def iteritems(self): 
 32              for k in self: 
 33                  yield (k, self[k]) 
 34 -        def iterkeys(self): 
 35              return self.__iter__() 
 36   
 37          # fourth level uses definitions from lower levels 
 38 -        def itervalues(self): 
 39              for _, v in self.iteritems(): 
 40                  yield v 
 41 -        def values(self): 
 42              return [v for _, v in self.iteritems()] 
 43 -        def items(self): 
 44              return list(self.iteritems()) 
 45 -        def clear(self): 
 46              for key in self.keys(): 
 47                  del self[key] 
 48 -        def setdefault(self, key, default=None): 
 49              try: 
 50                  return self[key] 
 51              except KeyError: 
 52                  self[key] = default 
 53              return default 
 54 -        def pop(self, key, *args): 
 55              if len(args) > 1: 
 56                  raise TypeError, "pop expected at most 2 arguments, got "\ 
 57                                    + repr(1 + len(args)) 
 58              try: 
 59                  value = self[key] 
 60              except KeyError: 
 61                  if args: 
 62                      return args[0] 
 63                  raise 
 64              del self[key] 
 65              return value 
 66 -        def popitem(self): 
 67              try: 
 68                  k, v = self.iteritems().next() 
 69              except StopIteration: 
 70                  raise KeyError, 'container is empty' 
 71              del self[k] 
 72              return (k, v) 
 73 -        def update(self, other=None, **kwargs): 
 74              # Make progressively weaker assumptions about "other" 
 75              if other is None: 
 76                  pass 
 77              elif hasattr(other, 'iteritems'):  # iteritems saves memory and lookups 
 78                  for k, v in other.iteritems(): 
 79                      self[k] = v 
 80              elif hasattr(other, 'keys'): 
 81                  for k in other.keys(): 
 82                      self[k] = other[k] 
 83              else: 
 84                  for k, v in other: 
 85                      self[k] = v 
 86              if kwargs: 
 87                  self.update(kwargs) 
 88 -        def get(self, key, default=None): 
 89              try: 
 90                  return self[key] 
 91              except KeyError: 
 92                  return default 
 93 -        def __repr__(self): 
 94              return repr(dict(self.iteritems())) 
 95 -        def __cmp__(self, other): 
 96              if other is None: 
 97                  return 1 
 98              if isinstance(other, DictMixin): 
 99                  other = dict(other.iteritems()) 
100              return cmp(dict(self.iteritems()), other) 
101 -        def __len__(self): 
102              return len(self.keys()) 
103