On Fri, Apr 1, 2016 at 2:09 PM Matthias welp <boekewurm@gmail.com> wrote:

> Function decorators

There are decorators that return a callable that not calls the function that was given as an argument, but also do some other things, and therefore change the behaviour of that function.

> So instead of
>
> a = Char(length=10, value='empty')
>
> you want
>
> @Char(length=10)
> a = 'empty'
>
> ?

If possible, yes. So that there is a standardized way to access changing variables, or to put limits on the content of the variable, similar to the @accepts and @produces decorators that are seen here (https://wiki.python.org/moin/PythonDecoratorLibrary#Type_Enforcement_.28accepts.2Freturns.29)

There is a standardized way. You can extend ``property`` or mimic its implementation. Then instead of

class Foo:

a = property(getter, no_cycles)

You can write

class Foo:

a = NoCycles()

I haven't linked to a how-to for doing this is, because I think it's unnecessary for most small projects. Every so often someone asks for a more pleasant syntax for specifying a property, getter and setter. Guido seems to consistently reply that he thinks our current situation is good enough. I'd dig up a link to the email archive for you, but Google wasn't being very kind to me.