unpickling was *not* a reference to the singleton but rather a new instance of the ``colander._null`` class. This was unintentional, because lots of code checks for ``if x is colander.null``, which will fail across pickling and unpickling. Now the reference created when ``colander.null`` is pickled is unpickled as the singleton itself.
External type objects should now inherit from ``colander.SchemaType`` to get a default implementation.
``default`` attributes, but you use it to perform serialization and deserialization without calling its ``bind`` method: - If ``validator`` is deferred, no validation will be performed. - If ``missing`` is deferred, the field will be considered *required*. - If ``default`` is deferred, the serialization default will be assumed to be ``colander.null``.
sets any unknown values within the ``**kw`` sequence as attributes of the node object.
declarative-looking spelling of schemas and schema nodes which have dependencies on values available after the schema has already been fully constructed. See the new narrative chapter in the documentation entitled "Schema Binding". - The interface of ``colander.SchemaNode`` has grown a ``__delitem__`` method. The ``__iter__``, and ``__getitem__`` methods have now also been properly documented.
``null`` value when required, it's a special marker value).
was added. It returns an iterable of error messages using the ``msg`` attribute of its related exception node. If the ``msg`` attribute is iterable, it is returned. If it is not iterable, a single-element list containing the ``msg`` value is returned.
``name``. Underscores in the ``name`` are replaced with empty strings and the first letter of every resulting word is capitalized. Previously the ``name`` was not split on underscores, and the entirety of the ``name`` was capitalized.
``widget`` keyword argument, for use by Deform (it is not used internally).
to ``colander.SchemaNode`` for roundtripping purposes. - Make it possible to pickle ``colander.null``.