[Python-Dev] TypeError messages

[Rob Cliffe]

On 21/02/2015 17:14, Antoine Pitrou wrote:
> On Fri, 20 Feb 2015 14:05:11 +0000
> Brett Cannon <brett at python.org> wrote:
>> On Thu Feb 19 2015 at 5:52:07 PM Serhiy Storchaka <storchaka at gmail.com>
>> wrote:
>>
>>> Different patterns for TypeError messages are used in the stdlib:
>>>
>>>       expected X, Y found
>>>       expected X, found Y
>>>       expected X, but Y found
>>>       expected X instance, Y found
>>>       X expected, not Y
>>>       expect X, not Y
>>>       need X, Y found
>>>       X is required, not Y
>>>       Z must be X, not Y
>>>       Z should be X, not Y
>>>
>>> and more.
>>>
>>> What the pattern is most preferable?
>>>
>> My preference is for "expected X, but found Y".
> If we are busy nitpicking, why are we saying "found Y"? Nothing was
> *found* by the callee, it just *got* an argument.
>
> So it should be "expected X, but got Y".
>
> Personally, I think the "but" is superfluous: the contradiction is
> already implied, so "expected X, got Y" is terser and conveys the
> meaning just as well.
>
> Regards
>
> Antoine.
+1
Rob Cliffe