blob: cbe7115bf9a48465caf3c014b388755b6ecebfa9 [file] [log] [blame]
Armin Ronachere791c2a2008-04-07 18:39:54 +02001# -*- coding: utf-8 -*-
2"""
3 jinja2.runtime
4 ~~~~~~~~~~~~~~
5
6 Runtime helpers.
7
8 :copyright: Copyright 2008 by Armin Ronacher.
9 :license: GNU GPL.
10"""
Armin Ronacher1ae4fdf2008-04-28 20:49:51 +020011import sys
Armin Ronacher4f7d2d52008-04-22 10:40:26 +020012from types import FunctionType
Armin Ronacherd1342312008-04-28 12:20:12 +020013from itertools import chain, imap
Armin Ronacher7ceced52008-05-03 10:15:31 +020014from jinja2.utils import Markup, partial, soft_unicode, escape, missing, concat
Armin Ronacherd1342312008-04-28 12:20:12 +020015from jinja2.exceptions import UndefinedError, TemplateRuntimeError
Armin Ronachere791c2a2008-04-07 18:39:54 +020016
17
Armin Ronacher2feed1d2008-04-26 16:26:52 +020018# these variables are exported to the template runtime
Armin Ronacher19cf9c22008-05-01 12:49:53 +020019__all__ = ['LoopContext', 'Context', 'TemplateReference', 'Macro', 'Markup',
20 'TemplateRuntimeError', 'missing', 'concat', 'escape',
Armin Ronacherd1342312008-04-28 12:20:12 +020021 'markup_join', 'unicode_join']
Armin Ronacher0611e492008-04-25 23:44:14 +020022
23
Armin Ronacherd1342312008-04-28 12:20:12 +020024def markup_join(*args):
25 """Concatenation that escapes if necessary and converts to unicode."""
26 buf = []
27 iterator = imap(soft_unicode, args)
28 for arg in iterator:
29 buf.append(arg)
30 if hasattr(arg, '__html__'):
31 return Markup(u'').join(chain(buf, iterator))
32 return concat(buf)
33
34
35def unicode_join(*args):
36 """Simple args to unicode conversion and concatenation."""
37 return concat(imap(unicode, args))
38
39
Armin Ronacher19cf9c22008-05-01 12:49:53 +020040class Context(object):
Armin Ronacher7259c762008-04-30 13:03:59 +020041 """The template context holds the variables of a template. It stores the
42 values passed to the template and also the names the template exports.
43 Creating instances is neither supported nor useful as it's created
44 automatically at various stages of the template evaluation and should not
45 be created by hand.
Armin Ronacherc9705c22008-04-27 21:28:03 +020046
Armin Ronacher7259c762008-04-30 13:03:59 +020047 The context is immutable. Modifications on :attr:`parent` **must not**
48 happen and modifications on :attr:`vars` are allowed from generated
49 template code only. Template filters and global functions marked as
50 :func:`contextfunction`\s get the active context passed as first argument
51 and are allowed to access the context read-only.
52
53 The template context supports read only dict operations (`get`,
Armin Ronacherf35e2812008-05-06 16:04:10 +020054 `keys`, `values`, `items`, `iterkeys`, `itervalues`, `iteritems`,
55 `__getitem__`, `__contains__`). Additionally there is a :meth:`resolve`
56 method that doesn't fail with a `KeyError` but returns an
57 :class:`Undefined` object for missing variables.
Armin Ronacher9706fab2008-04-08 18:49:56 +020058 """
Armin Ronachere791c2a2008-04-07 18:39:54 +020059
Armin Ronacher203bfcb2008-04-24 21:54:44 +020060 def __init__(self, environment, parent, name, blocks):
61 self.parent = parent
Armin Ronacher2feed1d2008-04-26 16:26:52 +020062 self.vars = vars = {}
Armin Ronacherc63243e2008-04-14 22:53:58 +020063 self.environment = environment
Armin Ronacher203bfcb2008-04-24 21:54:44 +020064 self.exported_vars = set()
Armin Ronacher68f77672008-04-17 11:50:39 +020065 self.name = name
Armin Ronacher203bfcb2008-04-24 21:54:44 +020066
67 # bind functions to the context of environment if required
Armin Ronacher2feed1d2008-04-26 16:26:52 +020068 for name, obj in parent.iteritems():
Armin Ronacher203bfcb2008-04-24 21:54:44 +020069 if type(obj) is FunctionType:
70 if getattr(obj, 'contextfunction', 0):
Armin Ronacher2feed1d2008-04-26 16:26:52 +020071 vars[name] = partial(obj, self)
Armin Ronacher203bfcb2008-04-24 21:54:44 +020072 elif getattr(obj, 'environmentfunction', 0):
Armin Ronacher2feed1d2008-04-26 16:26:52 +020073 vars[name] = partial(obj, environment)
Armin Ronacher203bfcb2008-04-24 21:54:44 +020074
75 # create the initial mapping of blocks. Whenever template inheritance
76 # takes place the runtime will update this mapping with the new blocks
77 # from the template.
Armin Ronacher75cfb862008-04-11 13:47:22 +020078 self.blocks = dict((k, [v]) for k, v in blocks.iteritems())
Armin Ronacherf059ec12008-04-11 22:21:00 +020079
Armin Ronacher203bfcb2008-04-24 21:54:44 +020080 def super(self, name, current):
Armin Ronacher62f8a292008-04-13 23:18:05 +020081 """Render a parent block."""
Armin Ronacherc9705c22008-04-27 21:28:03 +020082 try:
83 blocks = self.blocks[name]
Armin Ronacher83fbc0f2008-05-15 12:22:28 +020084 block = blocks[blocks.index(current) + 1]
Armin Ronacherc9705c22008-04-27 21:28:03 +020085 except LookupError:
Armin Ronacher9a822052008-04-17 18:44:07 +020086 return self.environment.undefined('there is no parent block '
Armin Ronacher19cf9c22008-05-01 12:49:53 +020087 'called %r.' % name,
88 name='super')
Armin Ronacherd1342312008-04-28 12:20:12 +020089 wrap = self.environment.autoescape and Markup or (lambda x: x)
Armin Ronacher83fbc0f2008-05-15 12:22:28 +020090 render = lambda: wrap(concat(block(self)))
Armin Ronacherc9705c22008-04-27 21:28:03 +020091 render.__name__ = render.name = name
92 return render
Armin Ronachere791c2a2008-04-07 18:39:54 +020093
Armin Ronacher53042292008-04-26 18:30:19 +020094 def get(self, key, default=None):
Armin Ronacher7259c762008-04-30 13:03:59 +020095 """Returns an item from the template context, if it doesn't exist
96 `default` is returned.
97 """
Armin Ronacherf35e2812008-05-06 16:04:10 +020098 try:
99 return self[key]
100 except KeyError:
101 return default
102
103 def resolve(self, key):
104 """Looks up a variable like `__getitem__` or `get` but returns an
105 :class:`Undefined` object with the name of the name looked up.
106 """
Armin Ronacher53042292008-04-26 18:30:19 +0200107 if key in self.vars:
108 return self.vars[key]
109 if key in self.parent:
110 return self.parent[key]
Armin Ronacherf35e2812008-05-06 16:04:10 +0200111 return self.environment.undefined(name=key)
Armin Ronacherb5124e62008-04-25 00:36:14 +0200112
Armin Ronacher9706fab2008-04-08 18:49:56 +0200113 def get_exported(self):
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200114 """Get a new dict with the exported variables."""
Armin Ronacherc9705c22008-04-27 21:28:03 +0200115 return dict((k, self.vars[k]) for k in self.exported_vars)
Armin Ronacher9706fab2008-04-08 18:49:56 +0200116
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200117 def get_all(self):
Armin Ronacher7259c762008-04-30 13:03:59 +0200118 """Return a copy of the complete context as dict including the
119 global variables.
120 """
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200121 return dict(self.parent, **self.vars)
122
Armin Ronacherf35e2812008-05-06 16:04:10 +0200123 def _all(meth):
124 def proxy(self):
125 return getattr(self.get_all(), meth)()
126 proxy.__doc__ = getattr(dict, meth).__doc__
127 proxy.__name__ = meth
128 return proxy
129
130 keys = _all('keys')
131 values = _all('values')
132 items = _all('items')
133 iterkeys = _all('iterkeys')
134 itervalues = _all('itervalues')
135 iteritems = _all('iteritems')
136 del _all
137
Armin Ronacherb5124e62008-04-25 00:36:14 +0200138 def __contains__(self, name):
139 return name in self.vars or name in self.parent
140
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200141 def __getitem__(self, key):
Armin Ronacherf35e2812008-05-06 16:04:10 +0200142 """Lookup a variable or raise `KeyError`."""
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200143 if key in self.vars:
144 return self.vars[key]
Armin Ronacherf35e2812008-05-06 16:04:10 +0200145 return self.parent[key]
Armin Ronacher4f62a9f2008-04-08 18:09:13 +0200146
Armin Ronacherf059ec12008-04-11 22:21:00 +0200147 def __repr__(self):
148 return '<%s %s of %r>' % (
149 self.__class__.__name__,
Armin Ronacher963f97d2008-04-25 11:44:59 +0200150 repr(self.get_all()),
Armin Ronacher68f77672008-04-17 11:50:39 +0200151 self.name
Armin Ronacherf059ec12008-04-11 22:21:00 +0200152 )
153
154
Armin Ronacherc9705c22008-04-27 21:28:03 +0200155class TemplateReference(object):
156 """The `self` in templates."""
Armin Ronacher62f8a292008-04-13 23:18:05 +0200157
Armin Ronacherc9705c22008-04-27 21:28:03 +0200158 def __init__(self, context):
159 self.__context = context
Armin Ronacher62f8a292008-04-13 23:18:05 +0200160
Armin Ronacherc9705c22008-04-27 21:28:03 +0200161 def __getitem__(self, name):
162 func = self.__context.blocks[name][-1]
Armin Ronacherd1342312008-04-28 12:20:12 +0200163 wrap = self.__context.environment.autoescape and \
164 Markup or (lambda x: x)
165 render = lambda: wrap(concat(func(self.__context)))
Armin Ronacherc9705c22008-04-27 21:28:03 +0200166 render.__name__ = render.name = name
167 return render
Armin Ronacher62f8a292008-04-13 23:18:05 +0200168
169 def __repr__(self):
170 return '<%s %r>' % (
171 self.__class__.__name__,
Armin Ronacherc9705c22008-04-27 21:28:03 +0200172 self._context.name
Armin Ronacher62f8a292008-04-13 23:18:05 +0200173 )
174
175
Armin Ronacher32a910f2008-04-26 23:21:03 +0200176class LoopContext(object):
177 """A loop context for dynamic iteration."""
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200178
Armin Ronacher1e1e8902008-05-11 23:21:16 +0200179 def __init__(self, iterable, enforce_length=False, recurse=None):
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200180 self._iterable = iterable
Armin Ronacher32a910f2008-04-26 23:21:03 +0200181 self._next = iter(iterable).next
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200182 self._length = None
Armin Ronacher1e1e8902008-05-11 23:21:16 +0200183 self._recurse = recurse
Armin Ronacher32a910f2008-04-26 23:21:03 +0200184 self.index0 = -1
185 if enforce_length:
186 len(self)
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200187
Armin Ronacher2e9396b2008-04-16 14:21:57 +0200188 def cycle(self, *args):
189 """A replacement for the old ``{% cycle %}`` tag."""
190 if not args:
191 raise TypeError('no items for cycling given')
192 return args[self.index0 % len(args)]
193
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200194 first = property(lambda x: x.index0 == 0)
195 last = property(lambda x: x.revindex0 == 0)
196 index = property(lambda x: x.index0 + 1)
Armin Ronacher10f3ba22008-04-18 11:30:37 +0200197 revindex = property(lambda x: x.length - x.index0)
198 revindex0 = property(lambda x: x.length - x.index)
Armin Ronacher2e9396b2008-04-16 14:21:57 +0200199
200 def __len__(self):
201 return self.length
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200202
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200203 def __iter__(self):
Armin Ronacher3d8b7842008-04-13 13:16:50 +0200204 return self
205
Armin Ronacher66a93442008-05-11 23:42:19 +0200206 def loop(self, iterable):
Armin Ronacher1e1e8902008-05-11 23:21:16 +0200207 if self._recurse is None:
208 raise TypeError('Tried to call non recursive loop. Maybe you '
Armin Ronacher66a93442008-05-11 23:42:19 +0200209 "forgot the 'recursive' modifier.")
Armin Ronacher1e1e8902008-05-11 23:21:16 +0200210 return self._recurse(iterable, self._recurse)
211
Armin Ronacher66a93442008-05-11 23:42:19 +0200212 # a nifty trick to enhance the error message if someone tried to call
213 # the the loop without or with too many arguments.
214 __call__ = loop; del loop
215
Armin Ronacher3d8b7842008-04-13 13:16:50 +0200216 def next(self):
217 self.index0 += 1
218 return self._next(), self
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200219
Armin Ronacher2e9396b2008-04-16 14:21:57 +0200220 @property
221 def length(self):
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200222 if self._length is None:
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200223 try:
224 length = len(self._iterable)
225 except TypeError:
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200226 self._iterable = tuple(self._iterable)
Armin Ronacher3d8b7842008-04-13 13:16:50 +0200227 self._next = iter(self._iterable).next
228 length = len(tuple(self._iterable)) + self.index0 + 1
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200229 self._length = length
230 return self._length
231
Armin Ronacher2e9396b2008-04-16 14:21:57 +0200232 def __repr__(self):
Armin Ronacherc9705c22008-04-27 21:28:03 +0200233 return '<%s %r/%r>' % (
234 self.__class__.__name__,
235 self.index,
236 self.length
237 )
Armin Ronacher2e9396b2008-04-16 14:21:57 +0200238
Armin Ronacher180a1bd2008-04-09 12:14:24 +0200239
Armin Ronacher4f62a9f2008-04-08 18:09:13 +0200240class Macro(object):
Armin Ronacherd55ab532008-04-09 16:13:39 +0200241 """Wraps a macro."""
Armin Ronacher4f62a9f2008-04-08 18:09:13 +0200242
Armin Ronacher963f97d2008-04-25 11:44:59 +0200243 def __init__(self, environment, func, name, arguments, defaults,
244 catch_kwargs, catch_varargs, caller):
Armin Ronacherc63243e2008-04-14 22:53:58 +0200245 self._environment = environment
Armin Ronacher71082072008-04-12 14:19:36 +0200246 self._func = func
Armin Ronacherd84ec462008-04-29 13:43:16 +0200247 self._argument_count = len(arguments)
Armin Ronacher4f62a9f2008-04-08 18:09:13 +0200248 self.name = name
249 self.arguments = arguments
250 self.defaults = defaults
Armin Ronacher963f97d2008-04-25 11:44:59 +0200251 self.catch_kwargs = catch_kwargs
252 self.catch_varargs = catch_varargs
Armin Ronacher71082072008-04-12 14:19:36 +0200253 self.caller = caller
Armin Ronacher4f62a9f2008-04-08 18:09:13 +0200254
255 def __call__(self, *args, **kwargs):
Armin Ronacher2feed1d2008-04-26 16:26:52 +0200256 arguments = []
Armin Ronacher9706fab2008-04-08 18:49:56 +0200257 for idx, name in enumerate(self.arguments):
258 try:
259 value = args[idx]
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200260 except:
Armin Ronacher9706fab2008-04-08 18:49:56 +0200261 try:
262 value = kwargs.pop(name)
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200263 except:
Armin Ronacher9706fab2008-04-08 18:49:56 +0200264 try:
Armin Ronacherd84ec462008-04-29 13:43:16 +0200265 value = self.defaults[idx - self._argument_count]
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200266 except:
Armin Ronacher9a822052008-04-17 18:44:07 +0200267 value = self._environment.undefined(
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200268 'parameter %r was not provided' % name, name=name)
Armin Ronacher2feed1d2008-04-26 16:26:52 +0200269 arguments.append(value)
270
271 # it's important that the order of these arguments does not change
272 # if not also changed in the compiler's `function_scoping` method.
273 # the order is caller, keyword arguments, positional arguments!
Armin Ronacher71082072008-04-12 14:19:36 +0200274 if self.caller:
275 caller = kwargs.pop('caller', None)
276 if caller is None:
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200277 caller = self._environment.undefined('No caller defined',
278 name='caller')
Armin Ronacher2feed1d2008-04-26 16:26:52 +0200279 arguments.append(caller)
Armin Ronacher963f97d2008-04-25 11:44:59 +0200280 if self.catch_kwargs:
Armin Ronacher2feed1d2008-04-26 16:26:52 +0200281 arguments.append(kwargs)
Armin Ronacher963f97d2008-04-25 11:44:59 +0200282 elif kwargs:
283 raise TypeError('macro %r takes no keyword argument %r' %
284 (self.name, iter(kwargs).next()))
285 if self.catch_varargs:
Armin Ronacherd84ec462008-04-29 13:43:16 +0200286 arguments.append(args[self._argument_count:])
Armin Ronacher19cf9c22008-05-01 12:49:53 +0200287 elif len(args) > self._argument_count:
288 raise TypeError('macro %r takes not more than %d argument(s)' %
289 (self.name, len(self.arguments)))
Armin Ronacher2feed1d2008-04-26 16:26:52 +0200290 return self._func(*arguments)
Armin Ronacher71082072008-04-12 14:19:36 +0200291
292 def __repr__(self):
293 return '<%s %s>' % (
294 self.__class__.__name__,
295 self.name is None and 'anonymous' or repr(self.name)
296 )
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200297
298
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200299def fail_with_undefined_error(self, *args, **kwargs):
300 """Regular callback function for undefined objects that raises an
301 `UndefinedError` on call.
302 """
303 if self._undefined_hint is None:
304 if self._undefined_obj is None:
305 hint = '%r is undefined' % self._undefined_name
306 elif not isinstance(self._undefined_name, basestring):
307 hint = '%r object has no element %r' % (
308 self._undefined_obj.__class__.__name__,
309 self._undefined_name
310 )
311 else:
312 hint = '%r object has no attribute %r' % (
313 self._undefined_obj.__class__.__name__,
314 self._undefined_name
315 )
316 else:
317 hint = self._undefined_hint
Armin Ronacher5cdc1ac2008-05-07 12:17:18 +0200318 raise self._undefined_exception(hint)
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200319
320
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200321class Undefined(object):
Armin Ronacherd1342312008-04-28 12:20:12 +0200322 """The default undefined type. This undefined type can be printed and
323 iterated over, but every other access will raise an :exc:`UndefinedError`:
324
325 >>> foo = Undefined(name='foo')
326 >>> str(foo)
327 ''
328 >>> not foo
329 True
330 >>> foo + 42
331 Traceback (most recent call last):
332 ...
333 jinja2.exceptions.UndefinedError: 'foo' is undefined
Armin Ronacherc63243e2008-04-14 22:53:58 +0200334 """
Armin Ronacher5cdc1ac2008-05-07 12:17:18 +0200335 __slots__ = ('_undefined_hint', '_undefined_obj', '_undefined_name',
336 '_undefined_exception')
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200337
Armin Ronacher5cdc1ac2008-05-07 12:17:18 +0200338 def __init__(self, hint=None, obj=None, name=None, exc=UndefinedError):
Armin Ronacher9a822052008-04-17 18:44:07 +0200339 self._undefined_hint = hint
340 self._undefined_obj = obj
341 self._undefined_name = name
Armin Ronacher5cdc1ac2008-05-07 12:17:18 +0200342 self._undefined_exception = exc
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200343
Armin Ronacherc63243e2008-04-14 22:53:58 +0200344 __add__ = __radd__ = __mul__ = __rmul__ = __div__ = __rdiv__ = \
345 __realdiv__ = __rrealdiv__ = __floordiv__ = __rfloordiv__ = \
346 __mod__ = __rmod__ = __pos__ = __neg__ = __call__ = \
Armin Ronacher53042292008-04-26 18:30:19 +0200347 __getattr__ = __getitem__ = __lt__ = __le__ = __gt__ = __ge__ = \
348 fail_with_undefined_error
Armin Ronacherc63243e2008-04-14 22:53:58 +0200349
350 def __str__(self):
351 return self.__unicode__().encode('utf-8')
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200352
353 def __repr__(self):
Priit Laes4149a0e2008-04-17 19:04:44 +0200354 return 'Undefined'
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200355
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200356 def __unicode__(self):
357 return u''
358
Armin Ronacherd1d2f3d2008-04-09 14:02:55 +0200359 def __len__(self):
360 return 0
361
362 def __iter__(self):
363 if 0:
364 yield None
Armin Ronacherc63243e2008-04-14 22:53:58 +0200365
366 def __nonzero__(self):
367 return False
368
369
370class DebugUndefined(Undefined):
Armin Ronacherd1342312008-04-28 12:20:12 +0200371 """An undefined that returns the debug info when printed.
372
373 >>> foo = DebugUndefined(name='foo')
374 >>> str(foo)
375 '{{ foo }}'
376 >>> not foo
377 True
378 >>> foo + 42
379 Traceback (most recent call last):
380 ...
381 jinja2.exceptions.UndefinedError: 'foo' is undefined
382 """
Armin Ronacher53042292008-04-26 18:30:19 +0200383 __slots__ = ()
Armin Ronacherc63243e2008-04-14 22:53:58 +0200384
385 def __unicode__(self):
Armin Ronacher9a822052008-04-17 18:44:07 +0200386 if self._undefined_hint is None:
387 if self._undefined_obj is None:
388 return u'{{ %s }}' % self._undefined_name
389 return '{{ no such element: %s[%r] }}' % (
390 self._undefined_obj.__class__.__name__,
391 self._undefined_name
392 )
393 return u'{{ undefined value printed: %s }}' % self._undefined_hint
Armin Ronacherc63243e2008-04-14 22:53:58 +0200394
395
396class StrictUndefined(Undefined):
Armin Ronacher203bfcb2008-04-24 21:54:44 +0200397 """An undefined that barks on print and iteration as well as boolean
Armin Ronacher53042292008-04-26 18:30:19 +0200398 tests and all kinds of comparisons. In other words: you can do nothing
399 with it except checking if it's defined using the `defined` test.
Armin Ronacherd1342312008-04-28 12:20:12 +0200400
401 >>> foo = StrictUndefined(name='foo')
402 >>> str(foo)
403 Traceback (most recent call last):
404 ...
405 jinja2.exceptions.UndefinedError: 'foo' is undefined
406 >>> not foo
407 Traceback (most recent call last):
408 ...
409 jinja2.exceptions.UndefinedError: 'foo' is undefined
410 >>> foo + 42
411 Traceback (most recent call last):
412 ...
413 jinja2.exceptions.UndefinedError: 'foo' is undefined
Priit Laes4149a0e2008-04-17 19:04:44 +0200414 """
Armin Ronacher53042292008-04-26 18:30:19 +0200415 __slots__ = ()
416 __iter__ = __unicode__ = __len__ = __nonzero__ = __eq__ = __ne__ = \
417 fail_with_undefined_error
Armin Ronacherc63243e2008-04-14 22:53:58 +0200418
Armin Ronacher53042292008-04-26 18:30:19 +0200419
420# remove remaining slots attributes, after the metaclass did the magic they
421# are unneeded and irritating as they contain wrong data for the subclasses.
422del Undefined.__slots__, DebugUndefined.__slots__, StrictUndefined.__slots__