> Btw, as usual, I would learn from what Mathematica is doing, because > the Hold(...) stuff seams really simple to me. So maybe the evaluate > keyword should be used in Python. We use the "evaluate" keyword > inconsistently in sympy so far.
Here is Mathematica's documentation for Hold: http://reference.wolfram.com/mathematica/ref/Hold.html In [1]: Hold[Evaluate[1 + 1], 2 + 2] Out[1]: Hold[2, 2+2] so this could be translated to Python along these lines: In [1]: [1+1, Hold(2+2)] Out[1] [2, 2+2] Where Hold function would just set some (global?) parameter for the __add__ function not to evaluate the stuff. I don't like this option much though. Another option: In [2]: [1+1, Add(2, 2, evaluate=False)] Out[2]: [2, 2 + 2] In fact, I executed [2] in SymPy... But honestly, Mathematica's way Hold[2+2] is simpler than Add(2, 2, evaluate=False). So, opinions on this? I don't like preparsing. Ondrej --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
