| Extending Astroid Syntax Tree |
| ============================= |
| |
| Sometimes Astroid will miss some potentially important information |
| users may wish to add, for instance with the standard library |
| `hashlib` module. In some other cases, users may want to customize the |
| way inference works, for instance to explain Astroid that calls to |
| `collections.namedtuple` are returning a class with some known |
| attributes. |
| |
| Modifications in the AST are now possible using the using the generic |
| transformation API. You can find examples in the `brain/` |
| subdirectory, which are taken from the the `pylint-brain`_ project. |
| |
| Transformation functions are registered using the `register_transform` method of |
| the Astroid manager: |
| |
| .. automethod:: astroid.manager.AstroidManager.register_transform |
| |
| To add filtering based on the `as_string` representation of the node |
| in addition to the type, the :class:`astroid.AsStringRegexpPredicate` |
| predicate object can be used. |
| |
| .. autoclass:: astroid.AsStringRegexpPredicate |
| |
| Last but not least, the :func:`inference_tip` function is there to register |
| a custom inference function. |
| |
| .. autofunction:: astroid.inference_tip |
| |
| .. _`pylint-brain`: https://bitbucket.org/logilab/pylint-brain |
