That's definitely a bug. Subclassing any class without changing anything shouldn't break anything. There are unfortunately several instances of this issue (see https://github.com/sympy/sympy/issues/6751). Probably somewhere in that code path something is referencing Add directly instead of using self.func, or doing a type comparison without using isinstance.
Aaron Meurer On Mon, Nov 9, 2015 at 10:48 AM, Duane Nykamp <[email protected]> wrote: > OK, I'm pretty sure this is a bug. I don't have to change Add at all to get > this infinite recursion, just create any subclass > > In [7]: Add(3,3,evaluate=False).evalf() > Out[7]: 6.00000000000000 > > In [8]: class Add2(Add): > ...: pass > ...: > > In [9]: Add2(3,3,evaluate=False).evalf() > RuntimeError: maximum recursion depth exceeded > > I can't figure out where the code is treating Add and its identical subclass > Add2 differently. > > Duane > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/60272dc0-8bf7-47db-83a9-01a840180943%40googlegroups.com. > > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6K9fmBQj1hYkdR7gUPTVV_k1FScZVNqQ8obfoPPt5HzYg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
