Class extension

Context manager for MDP extension.

This allows you to use extensions using a with statement, as in:

>>> with mdp.extension('extension_name'):
...     # 'node' is executed with the extension activated
...     node.execute(x)

It is also possible to activate multiple extensions at once:

>>> with mdp.extension(['ext1', 'ext2']):
...     # 'node' is executed with the two extensions activated
...     node.execute(x)

The deactivation at the end happens only for the extensions that were activated by this context manager (not for those that were already active when the context was entered). This prevents unintended side effects.

x.__init__(...) initializes x; see help(type(x)) for signature