r...@zedat.fu-berlin.de (Stefan Ram) writes: > Steve D'Aprano <steve+pyt...@pearwood.info> writes: >>For-each loops are MUCH easier to understand, and should be taught first. > > I prefer a bottom-up approach. > > For loops are based on iterators. > > So, "bottom-up" in this case means: iterators should be > taught before for-loops. > > But iterators are too abstract to be taught very early.
I think this may be a problem with your style. From your other postings, I think you value precision and exactness over broad understanding, and maybe you teach like that. I my view, it's possible to explain enough about iterators to understand a huge range of for loops without having to go into the gory details. I find the image of a conjurer pulling knotted hankies out of a hat a good one -- they may go on forever and you don't know if there is rabbit in there knotting them and deciding which colour comes next. > But I will teach iterators and for loops not much later than > while-loop. > > Maybe this way: Use a while-loop and try-catch to get values > from an iterator until exhausted, and then introduce the > for-loop as an abbreviation for that. That sounds very complicated, but I think I favour the other extreme to you. -- Ben. -- https://mail.python.org/mailman/listinfo/python-list
