summaryrefslogtreecommitdiff
path: root/paste/util/classinstance.py
blob: 6436a443d07429c7799cc14c7692287b665f9915 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php

class classinstancemethod(object):
    """
    Acts like a class method when called from a class, like an
    instance method when called by an instance.  The method should
    take two arguments, 'self' and 'cls'; one of these will be None
    depending on how the method was called.
    """

    def __init__(self, func):
        self.func = func
        self.__doc__ = func.__doc__

    def __get__(self, obj, type=None):
        return _methodwrapper(self.func, obj=obj, type=type)

class _methodwrapper(object):

    def __init__(self, func, obj, type):
        self.func = func
        self.obj = obj
        self.type = type

    def __call__(self, *args, **kw):
        assert 'self' not in kw and 'cls' not in kw, (
            "You cannot use 'self' or 'cls' arguments to a "
            "classinstancemethod")
        return self.func(*((self.obj, self.type) + args), **kw)

    def __repr__(self):
        if self.obj is None:
            return ('<bound class method %s.%s>'
                    % (self.type.__name__, self.func.func_name))
        else:
            return ('<bound method %s.%s of %r>'
                    % (self.type.__name__, self.func.func_name, self.obj))