[Python-ideas] ABC: what about the method arguments ?

[Dj Gilcrease]

On Thu, Sep 23, 2010 at 1:51 PM, Tarek Ziadé <ziade.tarek at gmail.com> wrote:
> Why are you thinking about unit tests  ? Don't you ever use
> issubclass/isinstance in your programs ?
>
> Checking signatures using ABC when you create a plugin system is one
> use case for instance.

This is something that I have implemented (before ABCs) in plugin
systems I use. When loading the plugin I validate all methods exist
and that each method has the correct number of required arguments, I
generally dont check argument name as my plugin systems all pass by
position instead of keyword. If the signature I am checking contains
*args it automatically passes the check. If the plugin fails the check
I dont load it.

On Thu, Sep 23, 2010 at 2:01 PM, Antoine Pitrou <solipsis at pitrou.net> wrote:
> Again, why do you want to check signatures? Do you not trust plugin
> authors to write plugins?

No, no I dont. I have had several plugin authors come to me
complaining that the plugin system is broken because it wont load
their plugin (even with a fairly detailed error message).


Dj Gilcrease
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