On Wednesday, May 13, 2015 at 10:25:18 AM UTC+5:30, Chris Angelico wrote: > On Wed, May 13, 2015 at 11:14 AM, Steven D'Aprano wrote: > > On Wed, 13 May 2015 02:05 am, Chris Angelico wrote: > > > >> So if you're writing a library function, it probably shouldn't use > >> print()... but your application is most welcome to. You usually know > >> which one you're writing at any given time. > > > > You might be, but beginners are not. > > I meant the generic "you" there. A beginner may well not know whether > to use / or //, whether it's better to use a list or a dict, etc etc > etc. That's what instructors are for. Make the distinction that > library functions shouldn't use print but application code can, and > then examples like this... > > > I'm not sure I accept Rustom's fix for the problem (I think that his cure is > > worse than the disease), but it is *hard* to get some beginners to use > > return instead of print: > > > > def add_twice(x, y): > > """Add twice y to x.""" > > print x + 2*y > > > > > > sort of thing. > > ... can be answered simply by explaining that "add_twice" ought to be > written as a library function rather than an application. It's the > exact same answer as this:
And later > Yep. I'd also use clear function/procedure names to make it more > visible, and probably tie this in with loops to show how you can print > more than one thing but can only return one. (Generators are a more > advanced topic.) [Structure of] Library function: basic Generator: advanced ?¿?¿ If you ask me that's sdrawkcab -- https://mail.python.org/mailman/listinfo/python-list
