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Diffstat (limited to 'lib/python2.7/copy_reg.py')
| -rw-r--r-- | lib/python2.7/copy_reg.py | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/lib/python2.7/copy_reg.py b/lib/python2.7/copy_reg.py deleted file mode 100644 index db17150..0000000 --- a/lib/python2.7/copy_reg.py +++ /dev/null @@ -1,201 +0,0 @@ -"""Helper to provide extensibility for pickle/cPickle. - -This is only useful to add pickle support for extension types defined in -C, not for instances of user-defined classes. -""" - -from types import ClassType as _ClassType - -__all__ = ["pickle", "constructor", - "add_extension", "remove_extension", "clear_extension_cache"] - -dispatch_table = {} - -def pickle(ob_type, pickle_function, constructor_ob=None): - if type(ob_type) is _ClassType: - raise TypeError("copy_reg is not intended for use with classes") - - if not hasattr(pickle_function, '__call__'): - raise TypeError("reduction functions must be callable") - dispatch_table[ob_type] = pickle_function - - # The constructor_ob function is a vestige of safe for unpickling. - # There is no reason for the caller to pass it anymore. - if constructor_ob is not None: - constructor(constructor_ob) - -def constructor(object): - if not hasattr(object, '__call__'): - raise TypeError("constructors must be callable") - -# Example: provide pickling support for complex numbers. - -try: - complex -except NameError: - pass -else: - - def pickle_complex(c): - return complex, (c.real, c.imag) - - pickle(complex, pickle_complex, complex) - -# Support for pickling new-style objects - -def _reconstructor(cls, base, state): - if base is object: - obj = object.__new__(cls) - else: - obj = base.__new__(cls, state) - if base.__init__ != object.__init__: - base.__init__(obj, state) - return obj - -_HEAPTYPE = 1<<9 - -# Python code for object.__reduce_ex__ for protocols 0 and 1 - -def _reduce_ex(self, proto): - assert proto < 2 - for base in self.__class__.__mro__: - if hasattr(base, '__flags__') and not base.__flags__ & _HEAPTYPE: - break - else: - base = object # not really reachable - if base is object: - state = None - else: - if base is self.__class__: - raise TypeError, "can't pickle %s objects" % base.__name__ - state = base(self) - args = (self.__class__, base, state) - try: - getstate = self.__getstate__ - except AttributeError: - if getattr(self, "__slots__", None): - raise TypeError("a class that defines __slots__ without " - "defining __getstate__ cannot be pickled") - try: - dict = self.__dict__ - except AttributeError: - dict = None - else: - dict = getstate() - if dict: - return _reconstructor, args, dict - else: - return _reconstructor, args - -# Helper for __reduce_ex__ protocol 2 - -def __newobj__(cls, *args): - return cls.__new__(cls, *args) - -def _slotnames(cls): - """Return a list of slot names for a given class. - - This needs to find slots defined by the class and its bases, so we - can't simply return the __slots__ attribute. We must walk down - the Method Resolution Order and concatenate the __slots__ of each - class found there. (This assumes classes don't modify their - __slots__ attribute to misrepresent their slots after the class is - defined.) - """ - - # Get the value from a cache in the class if possible - names = cls.__dict__.get("__slotnames__") - if names is not None: - return names - - # Not cached -- calculate the value - names = [] - if not hasattr(cls, "__slots__"): - # This class has no slots - pass - else: - # Slots found -- gather slot names from all base classes - for c in cls.__mro__: - if "__slots__" in c.__dict__: - slots = c.__dict__['__slots__'] - # if class has a single slot, it can be given as a string - if isinstance(slots, basestring): - slots = (slots,) - for name in slots: - # special descriptors - if name in ("__dict__", "__weakref__"): - continue - # mangled names - elif name.startswith('__') and not name.endswith('__'): - names.append('_%s%s' % (c.__name__, name)) - else: - names.append(name) - - # Cache the outcome in the class if at all possible - try: - cls.__slotnames__ = names - except: - pass # But don't die if we can't - - return names - -# A registry of extension codes. This is an ad-hoc compression -# mechanism. Whenever a global reference to <module>, <name> is about -# to be pickled, the (<module>, <name>) tuple is looked up here to see -# if it is a registered extension code for it. Extension codes are -# universal, so that the meaning of a pickle does not depend on -# context. (There are also some codes reserved for local use that -# don't have this restriction.) Codes are positive ints; 0 is -# reserved. - -_extension_registry = {} # key -> code -_inverted_registry = {} # code -> key -_extension_cache = {} # code -> object -# Don't ever rebind those names: cPickle grabs a reference to them when -# it's initialized, and won't see a rebinding. - -def add_extension(module, name, code): - """Register an extension code.""" - code = int(code) - if not 1 <= code <= 0x7fffffff: - raise ValueError, "code out of range" - key = (module, name) - if (_extension_registry.get(key) == code and - _inverted_registry.get(code) == key): - return # Redundant registrations are benign - if key in _extension_registry: - raise ValueError("key %s is already registered with code %s" % - (key, _extension_registry[key])) - if code in _inverted_registry: - raise ValueError("code %s is already in use for key %s" % - (code, _inverted_registry[code])) - _extension_registry[key] = code - _inverted_registry[code] = key - -def remove_extension(module, name, code): - """Unregister an extension code. For testing only.""" - key = (module, name) - if (_extension_registry.get(key) != code or - _inverted_registry.get(code) != key): - raise ValueError("key %s is not registered with code %s" % - (key, code)) - del _extension_registry[key] - del _inverted_registry[code] - if code in _extension_cache: - del _extension_cache[code] - -def clear_extension_cache(): - _extension_cache.clear() - -# Standard extension code assignments - -# Reserved ranges - -# First Last Count Purpose -# 1 127 127 Reserved for Python standard library -# 128 191 64 Reserved for Zope -# 192 239 48 Reserved for 3rd parties -# 240 255 16 Reserved for private use (will never be assigned) -# 256 Inf Inf Reserved for future assignment - -# Extension codes are assigned by the Python Software Foundation. |