[Python-ideas] Bring back callable()

Wed Nov 24 00:19:13 CET 2010

I admit defeat on this one.
On Tue, Nov 23, 2010 at 3:14 PM, Michael Foord
<fuzzyman at voidspace.org.uk> wrote:
>>> On 23 November 2010 23:01, Antoine Pitrou <solipsis at pitrou.net> wrote:
>>>> Hello,
>>>> Python 3 has removed callable() under the justification that's it's not
>> very useful and duck typing (EAFP) should be used instead. However,
>> it has since been felt by many people that it was an annoying loss;
>> there are situations where you truly want to know whether something is a
>> callable without actually calling it (for example when writing
>> sophisticated decorators, or simply when you want to inform the user
>> of an API misuse).
>>>> The substitute of writing `isinstance(x, collections.Callable)` is
>> not good, 1) because it's wordier 2) because collections is really not
>> an intuitive place where to look for a Callable ABC.
>>>> So, I would advocate bringing back the callable() builtin, which was
>> easy to use, helpful and semantically sane.
>> +1 I find it useful in Python 2. You have to know its limitations, but it is
> still useful.
>> Michael
>>>>> Regards
>>>> Antoine.
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