AlkantarClanX12
Current Path : /opt/alt/python33/lib64/python3.3/ |
Current File : //opt/alt/python33/lib64/python3.3/types.py |
""" Define names for built-in types that aren't directly accessible as a builtin. """ import sys # Iterators in Python aren't a matter of type but of protocol. A large # and changing number of builtin types implement *some* flavor of # iterator. Don't check the type! Use hasattr to check for both # "__iter__" and "__next__" attributes instead. def _f(): pass FunctionType = type(_f) LambdaType = type(lambda: None) # Same as FunctionType CodeType = type(_f.__code__) MappingProxyType = type(type.__dict__) SimpleNamespace = type(sys.implementation) def _g(): yield 1 GeneratorType = type(_g()) class _C: def _m(self): pass MethodType = type(_C()._m) BuiltinFunctionType = type(len) BuiltinMethodType = type([].append) # Same as BuiltinFunctionType ModuleType = type(sys) try: raise TypeError except TypeError: tb = sys.exc_info()[2] TracebackType = type(tb) FrameType = type(tb.tb_frame) tb = None; del tb # For Jython, the following two types are identical GetSetDescriptorType = type(FunctionType.__code__) MemberDescriptorType = type(FunctionType.__globals__) del sys, _f, _g, _C, # Not for export # Provide a PEP 3115 compliant mechanism for class creation def new_class(name, bases=(), kwds=None, exec_body=None): """Create a class object dynamically using the appropriate metaclass.""" meta, ns, kwds = prepare_class(name, bases, kwds) if exec_body is not None: exec_body(ns) return meta(name, bases, ns, **kwds) def prepare_class(name, bases=(), kwds=None): """Call the __prepare__ method of the appropriate metaclass. Returns (metaclass, namespace, kwds) as a 3-tuple *metaclass* is the appropriate metaclass *namespace* is the prepared class namespace *kwds* is an updated copy of the passed in kwds argument with any 'metaclass' entry removed. If no kwds argument is passed in, this will be an empty dict. """ if kwds is None: kwds = {} else: kwds = dict(kwds) # Don't alter the provided mapping if 'metaclass' in kwds: meta = kwds.pop('metaclass') else: if bases: meta = type(bases[0]) else: meta = type if isinstance(meta, type): # when meta is a type, we first determine the most-derived metaclass # instead of invoking the initial candidate directly meta = _calculate_meta(meta, bases) if hasattr(meta, '__prepare__'): ns = meta.__prepare__(name, bases, **kwds) else: ns = {} return meta, ns, kwds def _calculate_meta(meta, bases): """Calculate the most derived metaclass.""" winner = meta for base in bases: base_meta = type(base) if issubclass(winner, base_meta): continue if issubclass(base_meta, winner): winner = base_meta continue # else: raise TypeError("metaclass conflict: " "the metaclass of a derived class " "must be a (non-strict) subclass " "of the metaclasses of all its bases") return winner