anki/anki/hooks.py
2012-12-21 16:51:59 +09:00

63 lines
1.8 KiB
Python

# -*- coding: utf-8 -*-
# Copyright: Damien Elmes <anki@ichi2.net>
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
"""\
Hooks - hook management and tools for extending Anki
==============================================================================
To find available hooks, grep for runHook and runFilter in the source code.
Instrumenting allows you to modify functions that don't have hooks available.
If you call wrap() with pos='around', the original function will not be called
automatically but can be called with _old().
"""
# Hooks
##############################################################################
_hooks = {}
def runHook(hook, *args):
"Run all functions on hook."
hook = _hooks.get(hook, None)
if hook:
for func in hook:
func(*args)
def runFilter(hook, arg, *args):
hook = _hooks.get(hook, None)
if hook:
for func in hook:
arg = func(arg, *args)
return arg
def addHook(hook, func):
"Add a function to hook. Ignore if already on hook."
if not _hooks.get(hook, None):
_hooks[hook] = []
if func not in _hooks[hook]:
_hooks[hook].append(func)
def remHook(hook, func):
"Remove a function if is on hook."
hook = _hooks.get(hook, [])
if func in hook:
hook.remove(func)
# Instrumenting
##############################################################################
def wrap(old, new, pos="after"):
"Override an existing function."
def repl(*args, **kwargs):
if pos == "after":
old(*args, **kwargs)
return new(*args, **kwargs)
elif pos == "before":
new(*args, **kwargs)
return old(*args, **kwargs)
else:
return new(_old=old, *args, **kwargs)
return repl