manipulating class attributes from a decorator while the class is being defined

[Gerard Flanagan]

On Apr 19, 11:19 pm, Wilbert Berendsen <wbs... at xs4all.nl> wrote:
> Hi, is it possible to manipulate class attributes from within a decorator
> while the class is being defined?
>
> I want to register methods with some additional values in a class attribute.
> But I can't get a decorator to change a class attribute while the class is
> still being defined. Something like:
>
> class Parser(object):
>
>   regexps = []
>   def reg(regexp):
>     def deco(func):
>       regexps.append((regexp, func))
>       return func
>     return deco
>
>   @reg(r'".*"')
>   def quoted_string(self):
>     pass
>
> How can I reach the class attribute `regexps' from within a decorator?
>
> Thanks for any help,
> Wilbert Berendsen
>
> --http://www.wilbertberendsen.nl/
> "You must be the change you wish to see in the world."
>         -- Mahatma Gandhi

---------------------------------------------------

def reg(regexp):
    def deco(func):
        def inner(self, *args, **kw):
            if not hasattr(self, 'regexps'):
                self.regexps = []
            self.regexps.append((regexp, func))
            return func(self, *args, **kw)
        return inner
    return deco

class Parser(object):

    regexps = []


    @reg(r'".*"')
    def quoted_string(self):
        print 'hi'



p = Parser()

p.quoted_string()

print p.regexps
---------------------------------------------------