Eq is a mathematical equality, but it's also unevaluated, so that
doesn't really help.

This is just a bug in the printer. It should not sort the args on
unevaluated Add. Is there a way to detect that an Add was created with
evaluate=False?

Aaron Meurer

On Wed, Apr 30, 2014 at 2:40 AM, F. B. <[email protected]> wrote:
> I think it's a problem with the printer:
>
> In [1]: a = Add(3, 2, evaluate=False)
>
> In [2]: a.args
> Out[2]: (3, 2)
>
> In [3]: a
> Out[3]: 2 + 3
>
> The args are created in the correct order, it's the printer that apparently
> reorders the values. The structural equality is False because (2, 3) is not
> the same as (3, 2), and that sounds correct. Use Eq( , ) for mathematical
> equalities.
>
>
> On Wednesday, April 30, 2014 8:53:50 AM UTC+2, Duane Nykamp wrote:
>>
>> I really like how unevaluated operators are working.  However, one
>> confusing aspect is that, on display, the operands are reordered to some
>> standard order, but on comparison, the operator order matters.
>>
>> n [3]: Add(3,2,evaluate=False)
>> Out[3]: 2 + 3
>>
>> In [4]: Add(2,3,evaluate=False)
>> Out[4]: 2 + 3
>>
>> In [5]: Add(3,2,evaluate=False) == Add(2,3,evaluate=False)
>> Out[5]: False
>>
>>
>> Is it possible to make the comparison use the same scheme as the display?
>> It is confusing to get results that 2+3 is not the same as 2+3.
>>
>> Duane
>
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