smichr/sympy — comment on commit 0dca3dc37ae873b1ebfd3cc2a32c7694727beccc
File: sympy/simplify/simplify.py line 963
By asmeurer:

If you want that, it's better to just send the args as a list. Because this will screw with things if it is eventually returned. For example:

```
In [12]: Add(y, x, evaluate=False) == Add(x, y, evaluate=False)
Out[12]: False
```

In fact, I'm debating whether this should be considered a bug, and if Add should always sort args, even when they are unprocessed. I wonder how this would fit in with @rlamy's idea from http://code.google.com/p/sympy/issues/detail?id=2738.