[Python-Dev] Re: PEP 336, "Make None Callable", by Andrew McClelland

Tim Peters tim.peters at gmail.com
Thu Nov 4 04:25:41 CET 2004


[Anthony Baxter]
>> Abstract
>>
>>     None should be a callable object that when called with any
>>     arguments has no side effect and returns None.

> My response to this is simply "yuck". This is a hack, abd I
> don't think it's worthwhile.

Maybe it's not a coincidence that it's listed in the PEP index next to
"Reject Foolish Indentation" <0.9 wink>.

IMO, it's worse than not worthwhile:  it would be actively bad to
implement this.

    TypeError: 'NoneType' object is not callable

is a frequent runtime occurrence now, and performs a valuable service
when it happens by correctly pointing out a programming error. 
Python's None isn't meant to be neutral -- it's meant to mean "nothing
is there", and supplying nothing where something is required is a
logic error.


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