Add __getstate__() and __setstate__() methods

Fixes pickling of Options/MutableOptions instances with dill.

README.md

@@ -175,8 +175,9 @@ with the documentation for each option:
 
 ### `value_type`
 
-The value_type argument can be used to give a type or sequence of types that the option
-is allowed to have. Trying to set an option with a non-allowed type raises a
+The `value_type` argument can be used to give a type or sequence of types that
+the option is allowed to have. Trying to set an option with a non-allowed type
+raises a
 `ValueError`:
 ```python
 >>> d2 = D(d=-2)
@@ -387,6 +388,12 @@ or all values including defaults, by passing `True` to the `with_defaults` argum
 ```
 
 
+### Pickling (with dill)
+
+`Options` objects can be pickled using `dill`. This is tested. Pickling of
+`MutableOptions` objects is not currently supported.
+
+
 Examples
 --------
 

optionsfactory/optionsfactory.py

@@ -546,6 +546,14 @@ def __setattr__(self, key, value):
  raise TypeError("Options does not allow assigning to attributes")
  super(OptionsFactory.Options, self).__setattr__(key, value)
 
+ def __getstate__(self):
+ # Need to define this so that pickling with dill works
+ return vars(self)
+
+ def __setstate__(self, state):
+ # Need to define this so that pickling with dill works
+ vars(self).update(state)
+
  def is_default(self, key):
  try:
  return self.__is_default[key]