Source code for UserDict

"""A more or less complete user-defined wrapper around dictionary objects."""

[docs]class UserDict:
[docs] def __init__(*args, **kwargs): if not args: raise TypeError("descriptor '__init__' of 'UserDict' object " "needs an argument") self = args[0] args = args[1:] if len(args) > 1: raise TypeError('expected at most 1 arguments, got %d' % len(args)) if args: dict = args[0] elif 'dict' in kwargs: dict = kwargs.pop('dict') import warnings warnings.warn("Passing 'dict' as keyword argument is " "deprecated", PendingDeprecationWarning, stacklevel=2) else: dict = None self.data = {} if dict is not None: self.update(dict) if len(kwargs): self.update(kwargs)
def __repr__(self): return repr(self.data) def __cmp__(self, dict): if isinstance(dict, UserDict): return cmp(self.data, dict.data) else: return cmp(self.data, dict) __hash__ = None # Avoid Py3k warning 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]
[docs] def clear(self): self.data.clear()
[docs] 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
[docs] def keys(self): return self.data.keys()
[docs] def items(self): return self.data.items()
[docs] def iteritems(self): return self.data.iteritems()
[docs] def iterkeys(self): return self.data.iterkeys()
[docs] def itervalues(self): return self.data.itervalues()
[docs] def values(self): return self.data.values()
[docs] def has_key(self, key): return key in self.data
[docs] def update(*args, **kwargs): if not args: raise TypeError("descriptor 'update' of 'UserDict' object " "needs an argument") self = args[0] args = args[1:] if len(args) > 1: raise TypeError('expected at most 1 arguments, got %d' % len(args)) if args: dict = args[0] elif 'dict' in kwargs: dict = kwargs.pop('dict') import warnings warnings.warn("Passing 'dict' as keyword argument is deprecated", PendingDeprecationWarning, stacklevel=2) else: dict = None if dict is None: pass elif isinstance(dict, UserDict): self.data.update(dict.data) elif isinstance(dict, type({})) or not hasattr(dict, 'items'): self.data.update(dict) else: for k, v in dict.items(): self[k] = v if len(kwargs): self.data.update(kwargs)
[docs] def get(self, key, failobj=None): if key not in self: return failobj return self[key]
[docs] def setdefault(self, key, failobj=None): if key not in self: self[key] = failobj return self[key]
[docs] def pop(self, key, *args): return self.data.pop(key, *args)
[docs] def popitem(self): return self.data.popitem()
def __contains__(self, key): return key in self.data @classmethod
[docs] def fromkeys(cls, iterable, value=None): d = cls() for key in iterable: d[key] = value return d
class IterableUserDict(UserDict): def __iter__(self): return iter(self.data) import _abcoll _abcoll.MutableMapping.register(IterableUserDict)
[docs]class DictMixin: # Mixin defining all dictionary methods for classes that already have # a minimum dictionary interface including getitem, setitem, delitem, # and keys. Without knowledge of the subclass constructor, the mixin # does not define __init__() or copy(). In addition to the four base # methods, progressively more efficiency comes with defining # __contains__(), __iter__(), and iteritems(). # second level definitions support higher levels def __iter__(self): for k in self.keys(): yield k
[docs] def has_key(self, key): try: self[key] except KeyError: return False return True
def __contains__(self, key): return self.has_key(key) # third level takes advantage of second level definitions
[docs] def iteritems(self): for k in self: yield (k, self[k])
[docs] def iterkeys(self): return self.__iter__()
# fourth level uses definitions from lower levels
[docs] def itervalues(self): for _, v in self.iteritems(): yield v
[docs] def values(self): return [v for _, v in self.iteritems()]
[docs] def items(self): return list(self.iteritems())
[docs] def clear(self): for key in self.keys(): del self[key]
[docs] def setdefault(self, key, default=None): try: return self[key] except KeyError: self[key] = default return default
[docs] def pop(self, key, *args): if len(args) > 1: raise TypeError, "pop expected at most 2 arguments, got "\ + repr(1 + len(args)) try: value = self[key] except KeyError: if args: return args[0] raise del self[key] return value
[docs] def popitem(self): try: k, v = self.iteritems().next() except StopIteration: raise KeyError, 'container is empty' del self[k] return (k, v)
[docs] def update(self, other=None, **kwargs): # Make progressively weaker assumptions about "other" if other is None: pass elif hasattr(other, 'iteritems'): # iteritems saves memory and lookups for k, v in other.iteritems(): self[k] = v elif hasattr(other, 'keys'): for k in other.keys(): self[k] = other[k] else: for k, v in other: self[k] = v if kwargs: self.update(kwargs)
[docs] def get(self, key, default=None): try: return self[key] except KeyError: return default
def __repr__(self): return repr(dict(self.iteritems())) def __cmp__(self, other): if other is None: return 1 if isinstance(other, DictMixin): other = dict(other.iteritems()) return cmp(dict(self.iteritems()), other) def __len__(self): return len(self.keys())