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Is this considered black magic?

Christian Tanzer tanzer at swing.co.at
Mon Nov 12 03:34:41 EST 2001 
Laura Creighton <lac at strakt.com> wrote:

> I want to do something which is conceptually very simple.  Given a list of
> objects, call make everybody call the same method you want to run.  Sort
> of like apply(), but for methods.
> 
> This is what I came up with:
(snip)
> def foreach(name_key, object_list, *args):
>     print 'foreach: args are ' + `args`
>     for object in object_list:
>         try:
>             object.__class__.__dict__[name_key](object, *args)
>         except KeyError:
>             pass

Hi Laura, 

Using `__class__.__dict__` to access the method means that neither
inherited methods nor methods in the instance dictionary are handled
correctly.

`getattr` is the better choice (and less magic).

I'd also add `** kw` to the function.

Christian

-- 
Christian Tanzer                                         tanzer at swing.co.at
Glasauergasse 32                                       Tel: +43 1 876 62 36
A-1130 Vienna, Austria                                 Fax: +43 1 877 66 92
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