blank_attr_getter.py

from toolz import pipe


class Blank(object):
    """Forgive me Lord, for I have sinned.

    Inspired by implicit partial application in Coconut:
    http://coconut.readthedocs.io/en/master/DOCS.html#implicit-partial-application
    """
    def __getattr__(self, attr):

        def voodoo(*args):
            if len(args) == 1 and hasattr(args[0], attr):
                return getattr(args[0], attr)
            else:
                return lambda *more_args: voodoo(*more_args)(*args)

        return voodoo


class Object(object):
    """Just an Object."""
    def __init__(self, attr):
        super(Object, self).__init__()
        self.attr = attr

    def attr_plus(self, val):
        return self.attr + val

   
obj = Object(Object(1))
_ = Blank()

print(
    # These are equivalent.
    # Object(Object(1)) -> Object(1) -> 11
    pipe(obj, lambda x: x.attr, lambda x: x.attr_plus(10)),
    pipe(obj, _.attr, _.attr_plus(10)),
    sep='\n'
)