Mercurial has the ability to add new features through the use of

extensions. Extensions may add new commands, add options to

existing commands, change the default behavior of commands, or

implement hooks.

Extensions are not loaded by default for a variety of reasons:

they can increase startup overhead; they may be meant for advanced

usage only; they may provide potentially dangerous abilities (such

as letting you destroy or modify history); they might not be ready

for prime time; or they may alter some usual behaviors of stock

Mercurial. It is thus up to the user to activate extensions as

needed.

To enable the "foo" extension, either shipped with Mercurial or in the

Python search path, create an entry for it in your configuration file,

like this::

  [extensions]

  foo =

You may also specify the full path to an extension::

  [extensions]

  myfeature = ~/.hgext/myfeature.py

To explicitly disable an extension enabled in a configuration file of

broader scope, prepend its path with !::

  [extensions]

  # disabling extension bar residing in /path/to/extension/bar.py

  bar = !/path/to/extension/bar.py

  # ditto, but no path was supplied for extension baz

  baz = !