oop - How to catch any method called on an object in python? -

i'm looking pythonic solution on how store method called on object right inside object.

because in python, if want catch example abs() method, overload operator like:

catcher(object):     def __abs__(self):         self.function = abs  c = catcher() abs(c)  # c.function stores 'abs' called on c 

if want catch function, have other attribute in it, example pow(), i'm going use this:

catcher(object):     def __pow__(self, value):         self.function = pow         self.value = value  c = catcher() c ** 2  # c.function stores 'pow', , c.value stores '2' 

now, i'm looking general solution, catch , store kind of function called on catcher, without implementing overloads, , other cases. , can see, want store values (maybe in list, if there more 1 of them?) attributes of method.

thanks in advance!

a metaclass won't here; although special methods looked on type of current object (so class instances), __getattribute__ or __getattr__ not consulted when doing (probably because special methods). catch all dunder methods, forced create them all.

you can pretty decent list of operator special methods (__pow__, __gt__, etc.) enumerating operator module:

import operator operator_hooks = [name name in dir(operator) if name.startswith('__') , name.endswith('__')] 

armed list class decorator be:

def instrument_operator_hooks(cls):     def add_hook(name):         operator_func = getattr(operator, name.strip('_'), none)         existing = getattr(cls, name, none)          def op_hook(self, *args, **kw):             print "hooking {}".format(name)             self._function = operator_func             self._params = (args, kw)             if existing not none:                 return existing(self, *args, **kw)             raise attributeerror(name)          try:             setattr(cls, name, op_hook)         except (attributeerror, typeerror):             pass  # skip __name__ , __doc__ ,      hook_name in operator_hooks:         add_hook(hook_name)     return cls 

then apply class:

@instrument_operator_hooks class catchall(object):     pass 

demo:

>>> c = catchall() >>> c ** 2 hooking __pow__ traceback (most recent call last):   file "<stdin>", line 1, in <module>   file "<stdin>", line 11, in op_hook attributeerror: __pow__ >>> c._function <built-in function pow> >>> c._params ((2,), {}) 

so, though our class doesn't define __pow__ explicitly, still hooked it.