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- # -*- coding: utf-8 -*-
- """The runtime functions and state used by compiled templates."""
- import sys
- from itertools import chain
- from types import MethodType
- from markupsafe import escape # noqa: F401
- from markupsafe import Markup
- from markupsafe import soft_unicode
- from ._compat import abc
- from ._compat import imap
- from ._compat import implements_iterator
- from ._compat import implements_to_string
- from ._compat import iteritems
- from ._compat import PY2
- from ._compat import string_types
- from ._compat import text_type
- from ._compat import with_metaclass
- from .exceptions import TemplateNotFound # noqa: F401
- from .exceptions import TemplateRuntimeError # noqa: F401
- from .exceptions import UndefinedError
- from .nodes import EvalContext
- from .utils import concat
- from .utils import evalcontextfunction
- from .utils import internalcode
- from .utils import missing
- from .utils import Namespace # noqa: F401
- from .utils import object_type_repr
- # these variables are exported to the template runtime
- exported = [
- "LoopContext",
- "TemplateReference",
- "Macro",
- "Markup",
- "TemplateRuntimeError",
- "missing",
- "concat",
- "escape",
- "markup_join",
- "unicode_join",
- "to_string",
- "identity",
- "TemplateNotFound",
- "Namespace",
- "Undefined",
- ]
- #: the name of the function that is used to convert something into
- #: a string. We can just use the text type here.
- to_string = text_type
- def identity(x):
- """Returns its argument. Useful for certain things in the
- environment.
- """
- return x
- def markup_join(seq):
- """Concatenation that escapes if necessary and converts to unicode."""
- buf = []
- iterator = imap(soft_unicode, seq)
- for arg in iterator:
- buf.append(arg)
- if hasattr(arg, "__html__"):
- return Markup(u"").join(chain(buf, iterator))
- return concat(buf)
- def unicode_join(seq):
- """Simple args to unicode conversion and concatenation."""
- return concat(imap(text_type, seq))
- def new_context(
- environment,
- template_name,
- blocks,
- vars=None,
- shared=None,
- globals=None,
- locals=None,
- ):
- """Internal helper for context creation."""
- if vars is None:
- vars = {}
- if shared:
- parent = vars
- else:
- parent = dict(globals or (), **vars)
- if locals:
- # if the parent is shared a copy should be created because
- # we don't want to modify the dict passed
- if shared:
- parent = dict(parent)
- for key, value in iteritems(locals):
- if value is not missing:
- parent[key] = value
- return environment.context_class(environment, parent, template_name, blocks)
- class TemplateReference(object):
- """The `self` in templates."""
- def __init__(self, context):
- self.__context = context
- def __getitem__(self, name):
- blocks = self.__context.blocks[name]
- return BlockReference(name, self.__context, blocks, 0)
- def __repr__(self):
- return "<%s %r>" % (self.__class__.__name__, self.__context.name)
- def _get_func(x):
- return getattr(x, "__func__", x)
- class ContextMeta(type):
- def __new__(mcs, name, bases, d):
- rv = type.__new__(mcs, name, bases, d)
- if bases == ():
- return rv
- resolve = _get_func(rv.resolve)
- default_resolve = _get_func(Context.resolve)
- resolve_or_missing = _get_func(rv.resolve_or_missing)
- default_resolve_or_missing = _get_func(Context.resolve_or_missing)
- # If we have a changed resolve but no changed default or missing
- # resolve we invert the call logic.
- if (
- resolve is not default_resolve
- and resolve_or_missing is default_resolve_or_missing
- ):
- rv._legacy_resolve_mode = True
- elif (
- resolve is default_resolve
- and resolve_or_missing is default_resolve_or_missing
- ):
- rv._fast_resolve_mode = True
- return rv
- def resolve_or_missing(context, key, missing=missing):
- if key in context.vars:
- return context.vars[key]
- if key in context.parent:
- return context.parent[key]
- return missing
- class Context(with_metaclass(ContextMeta)):
- """The template context holds the variables of a template. It stores the
- values passed to the template and also the names the template exports.
- Creating instances is neither supported nor useful as it's created
- automatically at various stages of the template evaluation and should not
- be created by hand.
- The context is immutable. Modifications on :attr:`parent` **must not**
- happen and modifications on :attr:`vars` are allowed from generated
- template code only. Template filters and global functions marked as
- :func:`contextfunction`\\s get the active context passed as first argument
- and are allowed to access the context read-only.
- The template context supports read only dict operations (`get`,
- `keys`, `values`, `items`, `iterkeys`, `itervalues`, `iteritems`,
- `__getitem__`, `__contains__`). Additionally there is a :meth:`resolve`
- method that doesn't fail with a `KeyError` but returns an
- :class:`Undefined` object for missing variables.
- """
- # XXX: we want to eventually make this be a deprecation warning and
- # remove it.
- _legacy_resolve_mode = False
- _fast_resolve_mode = False
- def __init__(self, environment, parent, name, blocks):
- self.parent = parent
- self.vars = {}
- self.environment = environment
- self.eval_ctx = EvalContext(self.environment, name)
- self.exported_vars = set()
- self.name = name
- # create the initial mapping of blocks. Whenever template inheritance
- # takes place the runtime will update this mapping with the new blocks
- # from the template.
- self.blocks = dict((k, [v]) for k, v in iteritems(blocks))
- # In case we detect the fast resolve mode we can set up an alias
- # here that bypasses the legacy code logic.
- if self._fast_resolve_mode:
- self.resolve_or_missing = MethodType(resolve_or_missing, self)
- def super(self, name, current):
- """Render a parent block."""
- try:
- blocks = self.blocks[name]
- index = blocks.index(current) + 1
- blocks[index]
- except LookupError:
- return self.environment.undefined(
- "there is no parent block called %r." % name, name="super"
- )
- return BlockReference(name, self, blocks, index)
- def get(self, key, default=None):
- """Returns an item from the template context, if it doesn't exist
- `default` is returned.
- """
- try:
- return self[key]
- except KeyError:
- return default
- def resolve(self, key):
- """Looks up a variable like `__getitem__` or `get` but returns an
- :class:`Undefined` object with the name of the name looked up.
- """
- if self._legacy_resolve_mode:
- rv = resolve_or_missing(self, key)
- else:
- rv = self.resolve_or_missing(key)
- if rv is missing:
- return self.environment.undefined(name=key)
- return rv
- def resolve_or_missing(self, key):
- """Resolves a variable like :meth:`resolve` but returns the
- special `missing` value if it cannot be found.
- """
- if self._legacy_resolve_mode:
- rv = self.resolve(key)
- if isinstance(rv, Undefined):
- rv = missing
- return rv
- return resolve_or_missing(self, key)
- def get_exported(self):
- """Get a new dict with the exported variables."""
- return dict((k, self.vars[k]) for k in self.exported_vars)
- def get_all(self):
- """Return the complete context as dict including the exported
- variables. For optimizations reasons this might not return an
- actual copy so be careful with using it.
- """
- if not self.vars:
- return self.parent
- if not self.parent:
- return self.vars
- return dict(self.parent, **self.vars)
- @internalcode
- def call(__self, __obj, *args, **kwargs): # noqa: B902
- """Call the callable with the arguments and keyword arguments
- provided but inject the active context or environment as first
- argument if the callable is a :func:`contextfunction` or
- :func:`environmentfunction`.
- """
- if __debug__:
- __traceback_hide__ = True # noqa
- # Allow callable classes to take a context
- if hasattr(__obj, "__call__"): # noqa: B004
- fn = __obj.__call__
- for fn_type in (
- "contextfunction",
- "evalcontextfunction",
- "environmentfunction",
- ):
- if hasattr(fn, fn_type):
- __obj = fn
- break
- if callable(__obj):
- if getattr(__obj, "contextfunction", False) is True:
- args = (__self,) + args
- elif getattr(__obj, "evalcontextfunction", False) is True:
- args = (__self.eval_ctx,) + args
- elif getattr(__obj, "environmentfunction", False) is True:
- args = (__self.environment,) + args
- try:
- return __obj(*args, **kwargs)
- except StopIteration:
- return __self.environment.undefined(
- "value was undefined because "
- "a callable raised a "
- "StopIteration exception"
- )
- def derived(self, locals=None):
- """Internal helper function to create a derived context. This is
- used in situations where the system needs a new context in the same
- template that is independent.
- """
- context = new_context(
- self.environment, self.name, {}, self.get_all(), True, None, locals
- )
- context.eval_ctx = self.eval_ctx
- context.blocks.update((k, list(v)) for k, v in iteritems(self.blocks))
- return context
- def _all(meth): # noqa: B902
- def proxy(self):
- return getattr(self.get_all(), meth)()
- proxy.__doc__ = getattr(dict, meth).__doc__
- proxy.__name__ = meth
- return proxy
- keys = _all("keys")
- values = _all("values")
- items = _all("items")
- # not available on python 3
- if PY2:
- iterkeys = _all("iterkeys")
- itervalues = _all("itervalues")
- iteritems = _all("iteritems")
- del _all
- def __contains__(self, name):
- return name in self.vars or name in self.parent
- def __getitem__(self, key):
- """Lookup a variable or raise `KeyError` if the variable is
- undefined.
- """
- item = self.resolve_or_missing(key)
- if item is missing:
- raise KeyError(key)
- return item
- def __repr__(self):
- return "<%s %s of %r>" % (
- self.__class__.__name__,
- repr(self.get_all()),
- self.name,
- )
- abc.Mapping.register(Context)
- class BlockReference(object):
- """One block on a template reference."""
- def __init__(self, name, context, stack, depth):
- self.name = name
- self._context = context
- self._stack = stack
- self._depth = depth
- @property
- def super(self):
- """Super the block."""
- if self._depth + 1 >= len(self._stack):
- return self._context.environment.undefined(
- "there is no parent block called %r." % self.name, name="super"
- )
- return BlockReference(self.name, self._context, self._stack, self._depth + 1)
- @internalcode
- def __call__(self):
- rv = concat(self._stack[self._depth](self._context))
- if self._context.eval_ctx.autoescape:
- rv = Markup(rv)
- return rv
- @implements_iterator
- class LoopContext:
- """A wrapper iterable for dynamic ``for`` loops, with information
- about the loop and iteration.
- """
- #: Current iteration of the loop, starting at 0.
- index0 = -1
- _length = None
- _after = missing
- _current = missing
- _before = missing
- _last_changed_value = missing
- def __init__(self, iterable, undefined, recurse=None, depth0=0):
- """
- :param iterable: Iterable to wrap.
- :param undefined: :class:`Undefined` class to use for next and
- previous items.
- :param recurse: The function to render the loop body when the
- loop is marked recursive.
- :param depth0: Incremented when looping recursively.
- """
- self._iterable = iterable
- self._iterator = self._to_iterator(iterable)
- self._undefined = undefined
- self._recurse = recurse
- #: How many levels deep a recursive loop currently is, starting at 0.
- self.depth0 = depth0
- @staticmethod
- def _to_iterator(iterable):
- return iter(iterable)
- @property
- def length(self):
- """Length of the iterable.
- If the iterable is a generator or otherwise does not have a
- size, it is eagerly evaluated to get a size.
- """
- if self._length is not None:
- return self._length
- try:
- self._length = len(self._iterable)
- except TypeError:
- iterable = list(self._iterator)
- self._iterator = self._to_iterator(iterable)
- self._length = len(iterable) + self.index + (self._after is not missing)
- return self._length
- def __len__(self):
- return self.length
- @property
- def depth(self):
- """How many levels deep a recursive loop currently is, starting at 1."""
- return self.depth0 + 1
- @property
- def index(self):
- """Current iteration of the loop, starting at 1."""
- return self.index0 + 1
- @property
- def revindex0(self):
- """Number of iterations from the end of the loop, ending at 0.
- Requires calculating :attr:`length`.
- """
- return self.length - self.index
- @property
- def revindex(self):
- """Number of iterations from the end of the loop, ending at 1.
- Requires calculating :attr:`length`.
- """
- return self.length - self.index0
- @property
- def first(self):
- """Whether this is the first iteration of the loop."""
- return self.index0 == 0
- def _peek_next(self):
- """Return the next element in the iterable, or :data:`missing`
- if the iterable is exhausted. Only peeks one item ahead, caching
- the result in :attr:`_last` for use in subsequent checks. The
- cache is reset when :meth:`__next__` is called.
- """
- if self._after is not missing:
- return self._after
- self._after = next(self._iterator, missing)
- return self._after
- @property
- def last(self):
- """Whether this is the last iteration of the loop.
- Causes the iterable to advance early. See
- :func:`itertools.groupby` for issues this can cause.
- The :func:`groupby` filter avoids that issue.
- """
- return self._peek_next() is missing
- @property
- def previtem(self):
- """The item in the previous iteration. Undefined during the
- first iteration.
- """
- if self.first:
- return self._undefined("there is no previous item")
- return self._before
- @property
- def nextitem(self):
- """The item in the next iteration. Undefined during the last
- iteration.
- Causes the iterable to advance early. See
- :func:`itertools.groupby` for issues this can cause.
- The :func:`groupby` filter avoids that issue.
- """
- rv = self._peek_next()
- if rv is missing:
- return self._undefined("there is no next item")
- return rv
- def cycle(self, *args):
- """Return a value from the given args, cycling through based on
- the current :attr:`index0`.
- :param args: One or more values to cycle through.
- """
- if not args:
- raise TypeError("no items for cycling given")
- return args[self.index0 % len(args)]
- def changed(self, *value):
- """Return ``True`` if previously called with a different value
- (including when called for the first time).
- :param value: One or more values to compare to the last call.
- """
- if self._last_changed_value != value:
- self._last_changed_value = value
- return True
- return False
- def __iter__(self):
- return self
- def __next__(self):
- if self._after is not missing:
- rv = self._after
- self._after = missing
- else:
- rv = next(self._iterator)
- self.index0 += 1
- self._before = self._current
- self._current = rv
- return rv, self
- @internalcode
- def __call__(self, iterable):
- """When iterating over nested data, render the body of the loop
- recursively with the given inner iterable data.
- The loop must have the ``recursive`` marker for this to work.
- """
- if self._recurse is None:
- raise TypeError(
- "The loop must have the 'recursive' marker to be called recursively."
- )
- return self._recurse(iterable, self._recurse, depth=self.depth)
- def __repr__(self):
- return "<%s %d/%d>" % (self.__class__.__name__, self.index, self.length)
- class Macro(object):
- """Wraps a macro function."""
- def __init__(
- self,
- environment,
- func,
- name,
- arguments,
- catch_kwargs,
- catch_varargs,
- caller,
- default_autoescape=None,
- ):
- self._environment = environment
- self._func = func
- self._argument_count = len(arguments)
- self.name = name
- self.arguments = arguments
- self.catch_kwargs = catch_kwargs
- self.catch_varargs = catch_varargs
- self.caller = caller
- self.explicit_caller = "caller" in arguments
- if default_autoescape is None:
- default_autoescape = environment.autoescape
- self._default_autoescape = default_autoescape
- @internalcode
- @evalcontextfunction
- def __call__(self, *args, **kwargs):
- # This requires a bit of explanation, In the past we used to
- # decide largely based on compile-time information if a macro is
- # safe or unsafe. While there was a volatile mode it was largely
- # unused for deciding on escaping. This turns out to be
- # problematic for macros because whether a macro is safe depends not
- # on the escape mode when it was defined, but rather when it was used.
- #
- # Because however we export macros from the module system and
- # there are historic callers that do not pass an eval context (and
- # will continue to not pass one), we need to perform an instance
- # check here.
- #
- # This is considered safe because an eval context is not a valid
- # argument to callables otherwise anyway. Worst case here is
- # that if no eval context is passed we fall back to the compile
- # time autoescape flag.
- if args and isinstance(args[0], EvalContext):
- autoescape = args[0].autoescape
- args = args[1:]
- else:
- autoescape = self._default_autoescape
- # try to consume the positional arguments
- arguments = list(args[: self._argument_count])
- off = len(arguments)
- # For information why this is necessary refer to the handling
- # of caller in the `macro_body` handler in the compiler.
- found_caller = False
- # if the number of arguments consumed is not the number of
- # arguments expected we start filling in keyword arguments
- # and defaults.
- if off != self._argument_count:
- for name in self.arguments[len(arguments) :]:
- try:
- value = kwargs.pop(name)
- except KeyError:
- value = missing
- if name == "caller":
- found_caller = True
- arguments.append(value)
- else:
- found_caller = self.explicit_caller
- # it's important that the order of these arguments does not change
- # if not also changed in the compiler's `function_scoping` method.
- # the order is caller, keyword arguments, positional arguments!
- if self.caller and not found_caller:
- caller = kwargs.pop("caller", None)
- if caller is None:
- caller = self._environment.undefined("No caller defined", name="caller")
- arguments.append(caller)
- if self.catch_kwargs:
- arguments.append(kwargs)
- elif kwargs:
- if "caller" in kwargs:
- raise TypeError(
- "macro %r was invoked with two values for "
- "the special caller argument. This is "
- "most likely a bug." % self.name
- )
- raise TypeError(
- "macro %r takes no keyword argument %r"
- % (self.name, next(iter(kwargs)))
- )
- if self.catch_varargs:
- arguments.append(args[self._argument_count :])
- elif len(args) > self._argument_count:
- raise TypeError(
- "macro %r takes not more than %d argument(s)"
- % (self.name, len(self.arguments))
- )
- return self._invoke(arguments, autoescape)
- def _invoke(self, arguments, autoescape):
- """This method is being swapped out by the async implementation."""
- rv = self._func(*arguments)
- if autoescape:
- rv = Markup(rv)
- return rv
- def __repr__(self):
- return "<%s %s>" % (
- self.__class__.__name__,
- self.name is None and "anonymous" or repr(self.name),
- )
- @implements_to_string
- class Undefined(object):
- """The default undefined type. This undefined type can be printed and
- iterated over, but every other access will raise an :exc:`UndefinedError`:
- >>> foo = Undefined(name='foo')
- >>> str(foo)
- ''
- >>> not foo
- True
- >>> foo + 42
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- """
- __slots__ = (
- "_undefined_hint",
- "_undefined_obj",
- "_undefined_name",
- "_undefined_exception",
- )
- def __init__(self, hint=None, obj=missing, name=None, exc=UndefinedError):
- self._undefined_hint = hint
- self._undefined_obj = obj
- self._undefined_name = name
- self._undefined_exception = exc
- @property
- def _undefined_message(self):
- """Build a message about the undefined value based on how it was
- accessed.
- """
- if self._undefined_hint:
- return self._undefined_hint
- if self._undefined_obj is missing:
- return "%r is undefined" % self._undefined_name
- if not isinstance(self._undefined_name, string_types):
- return "%s has no element %r" % (
- object_type_repr(self._undefined_obj),
- self._undefined_name,
- )
- return "%r has no attribute %r" % (
- object_type_repr(self._undefined_obj),
- self._undefined_name,
- )
- @internalcode
- def _fail_with_undefined_error(self, *args, **kwargs):
- """Raise an :exc:`UndefinedError` when operations are performed
- on the undefined value.
- """
- raise self._undefined_exception(self._undefined_message)
- @internalcode
- def __getattr__(self, name):
- if name[:2] == "__":
- raise AttributeError(name)
- return self._fail_with_undefined_error()
- __add__ = (
- __radd__
- ) = (
- __mul__
- ) = (
- __rmul__
- ) = (
- __div__
- ) = (
- __rdiv__
- ) = (
- __truediv__
- ) = (
- __rtruediv__
- ) = (
- __floordiv__
- ) = (
- __rfloordiv__
- ) = (
- __mod__
- ) = (
- __rmod__
- ) = (
- __pos__
- ) = (
- __neg__
- ) = (
- __call__
- ) = (
- __getitem__
- ) = (
- __lt__
- ) = (
- __le__
- ) = (
- __gt__
- ) = (
- __ge__
- ) = (
- __int__
- ) = (
- __float__
- ) = (
- __complex__
- ) = __pow__ = __rpow__ = __sub__ = __rsub__ = _fail_with_undefined_error
- def __eq__(self, other):
- return type(self) is type(other)
- def __ne__(self, other):
- return not self.__eq__(other)
- def __hash__(self):
- return id(type(self))
- def __str__(self):
- return u""
- def __len__(self):
- return 0
- def __iter__(self):
- if 0:
- yield None
- def __nonzero__(self):
- return False
- __bool__ = __nonzero__
- def __repr__(self):
- return "Undefined"
- def make_logging_undefined(logger=None, base=None):
- """Given a logger object this returns a new undefined class that will
- log certain failures. It will log iterations and printing. If no
- logger is given a default logger is created.
- Example::
- logger = logging.getLogger(__name__)
- LoggingUndefined = make_logging_undefined(
- logger=logger,
- base=Undefined
- )
- .. versionadded:: 2.8
- :param logger: the logger to use. If not provided, a default logger
- is created.
- :param base: the base class to add logging functionality to. This
- defaults to :class:`Undefined`.
- """
- if logger is None:
- import logging
- logger = logging.getLogger(__name__)
- logger.addHandler(logging.StreamHandler(sys.stderr))
- if base is None:
- base = Undefined
- def _log_message(undef):
- if undef._undefined_hint is None:
- if undef._undefined_obj is missing:
- hint = "%s is undefined" % undef._undefined_name
- elif not isinstance(undef._undefined_name, string_types):
- hint = "%s has no element %s" % (
- object_type_repr(undef._undefined_obj),
- undef._undefined_name,
- )
- else:
- hint = "%s has no attribute %s" % (
- object_type_repr(undef._undefined_obj),
- undef._undefined_name,
- )
- else:
- hint = undef._undefined_hint
- logger.warning("Template variable warning: %s", hint)
- class LoggingUndefined(base):
- def _fail_with_undefined_error(self, *args, **kwargs):
- try:
- return base._fail_with_undefined_error(self, *args, **kwargs)
- except self._undefined_exception as e:
- logger.error("Template variable error: %s", str(e))
- raise e
- def __str__(self):
- rv = base.__str__(self)
- _log_message(self)
- return rv
- def __iter__(self):
- rv = base.__iter__(self)
- _log_message(self)
- return rv
- if PY2:
- def __nonzero__(self):
- rv = base.__nonzero__(self)
- _log_message(self)
- return rv
- def __unicode__(self):
- rv = base.__unicode__(self)
- _log_message(self)
- return rv
- else:
- def __bool__(self):
- rv = base.__bool__(self)
- _log_message(self)
- return rv
- return LoggingUndefined
- # No @implements_to_string decorator here because __str__
- # is not overwritten from Undefined in this class.
- # This would cause a recursion error in Python 2.
- class ChainableUndefined(Undefined):
- """An undefined that is chainable, where both ``__getattr__`` and
- ``__getitem__`` return itself rather than raising an
- :exc:`UndefinedError`.
- >>> foo = ChainableUndefined(name='foo')
- >>> str(foo.bar['baz'])
- ''
- >>> foo.bar['baz'] + 42
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- .. versionadded:: 2.11.0
- """
- __slots__ = ()
- def __html__(self):
- return self.__str__()
- def __getattr__(self, _):
- return self
- __getitem__ = __getattr__
- @implements_to_string
- class DebugUndefined(Undefined):
- """An undefined that returns the debug info when printed.
- >>> foo = DebugUndefined(name='foo')
- >>> str(foo)
- '{{ foo }}'
- >>> not foo
- True
- >>> foo + 42
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- """
- __slots__ = ()
- def __str__(self):
- if self._undefined_hint is None:
- if self._undefined_obj is missing:
- return u"{{ %s }}" % self._undefined_name
- return "{{ no such element: %s[%r] }}" % (
- object_type_repr(self._undefined_obj),
- self._undefined_name,
- )
- return u"{{ undefined value printed: %s }}" % self._undefined_hint
- @implements_to_string
- class StrictUndefined(Undefined):
- """An undefined that barks on print and iteration as well as boolean
- tests and all kinds of comparisons. In other words: you can do nothing
- with it except checking if it's defined using the `defined` test.
- >>> foo = StrictUndefined(name='foo')
- >>> str(foo)
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- >>> not foo
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- >>> foo + 42
- Traceback (most recent call last):
- ...
- jinja2.exceptions.UndefinedError: 'foo' is undefined
- """
- __slots__ = ()
- __iter__ = (
- __str__
- ) = (
- __len__
- ) = (
- __nonzero__
- ) = __eq__ = __ne__ = __bool__ = __hash__ = Undefined._fail_with_undefined_error
- # remove remaining slots attributes, after the metaclass did the magic they
- # are unneeded and irritating as they contain wrong data for the subclasses.
- del (
- Undefined.__slots__,
- ChainableUndefined.__slots__,
- DebugUndefined.__slots__,
- StrictUndefined.__slots__,
- )
|