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a_list.count(a_callable) ?

Ping ping.nsr.yeh at gmail.com
Fri Jun 15 10:15:37 EDT 2007 
>
> sum(1 for i in a_list if a_callable(i))
>
> --
> Carsten Haesehttp://informixdb.sourceforge.net

This works nicely but not very intuitive or readable to me.

First of all, the generator expression makes sense only to
trained eyes.  Secondly, using sum(1 ...) to mean count()
isn't very intuitive either.

I would still prefer an expression like a_list.count(a_callable),
which is short, clean, and easy to understand.   :)   However,
it does produce ambiguities if a_list is a list of callables.
Should the count() method match values or check return values
of a_callable?  There are several possible designs but I'm not
sure which is better.

Ping
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