Extending¶
Each attrs
-decorated class has a __attrs_attrs__
class attribute.
It is a tuple of attr.Attribute
carrying meta-data about each attribute.
So it is fairly simple to build your own decorators on top of attrs
:
>>> import attr
>>> def print_attrs(cls):
... print(cls.__attrs_attrs__)
>>> @print_attrs
... @attr.s
... class C(object):
... a = attr.ib()
(Attribute(name='a', default=NOTHING, validator=None, repr=True, cmp=True, hash=True, init=True, convert=None),)
Warning
The attr.s()
decorator must be applied first because it puts __attrs_attrs__
in place!
That means that is has to come after your decorator because:
@a
@b
def f():
pass
is just syntactic sugar for:
def original_f():
pass
f = a(b(original_f))