def decorator_with_args(decf):
    def _inner(*dec_args):
        def _decorated(realf):
            def _inner2(*args,**kwargs):
                return decf(realf,*(dec_args + args),**kwargs)
            return _inner2
        return _decorated
    return _inner

def decorator(decf):
    def _decorated(realf):
        def _inner(*args,**kwargs):
            return decf(realf,*args,**kwargs)
        return _inner
    return _decorated

# A decorator without parameters is a function
# that takes a function as single argument and
# returns a function of the same signature as
# given.
#
# A decorator with parameters is a function that
# takse those parameters and returns a decorator
# without parameters as defined above.
#
# An argument-taking meta-decorator is a
# decorator that takes a function and returns a
# decorator as if it where defined as above

@decorator_with_args
def pre(real_fun,pre_fun,*args,**kwargs):
    pre_fun(*args,**kwargs)
    return real_fun(*args,**kwargs)

@decorator
def post(real_fun,*args,**kwargs):
    ret = real_fun(*args,**kwargs)
    print "AFTER!"
    return ret

def before(*args,**kwargs):
    print "BEFORE!"
    print "args = " + repr(args)
    print "kwargs = " + repr(kwargs)

@pre(before)
@post
def mainfun(x,y,a=True,b=False):
    print "MAIN!"
    print "x = %s, y = %s" % (x,y)
    print "a = %s, b = %s" % (a,b)