[Cython] Fwd: Re: [cython-users] checking for "None" in nogil function

Stefan Behnel stefan_ml at behnel.de
Tue May 8 06:41:04 CEST 2012

Greg Ewing, 08.05.2012 02:05:
> Stefan Behnel wrote:
>> The main reason we didn't change this behaviour back then was that it would
>> clearly break user code and we thought we could do without that. That's
>> different from considering it "right" and "good".
> I changed the None-checking behaviour in Pyrex because I *wanted*
> to break user code. Or rather, I didn't think it would be a
> bad thing to make people revisit their code and think properly
> about whether they really wanted to allow None in each case.

The problem here is that it's not very likely that people specifically
tested their code with None values, especially if they didn't carefully
think of it already when writing it.

So changing the default to make people think may not result in making them
think before their code starts throwing exceptions somewhere in production.
And having to revisit a large amount of code at that point may turn out to
be rather expensive.


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