On Mon, 6 Nov 2017 12:54 am, Stefan Ram wrote: > Paul Moore <p.f.mo...@gmail.com> writes: >>But regardless, the Zen isn't intended to be taken quite as literally >>as the OP was trying to do. It's a statement of principles, not a set >>of rules. > > What I am looking for is a default notation to use in my > beginner's tutorial and also to recommand for beginners.
When I first started learning Python, I had a bit of difficulty with the two import forms. For about an hour, until I experimented in the interactive interpreter until I got it. Part of the problem at the time was that I had no concept of "namespaces" or modules. If your students are experienced in other languages, don't treat them like dummies. They'll probably understand about namespaces and variable scopes. Teach them that math.cos is the syntax for accessing a name "cos" inside the "math" namespace, and they'll get it. Teach them that the from...import version brings the name into the current scope, and they'll get that too. You might have to give them analogous examples from whatever languages they're used to. If your students are completely new to this, like I was, then it might help to start them with just the "import math" form, and then later introduce "from...import" as syntactic sugar for: import math cos = math.cos del math Although I wouldn't literally teach `del` at this point, I'd just leave it out and and "except that the name 'math' isn't actually made available". > Learners have a limited capacity for learning and storing > information. People don't learn isolated facts too well. But they learn *models* which they can then infer behaviour from VERY well. This is why the Principle of Least Surprise is so important for usable interfaces and APIs. If you try to teach things as isolated facts, students will struggle. But: - teach import math first; - then show how `from math import cos` is syntactic sugar for making a local alias for math.cos; - then you can show that there's no particular reason why the names have to be the same: from math import cos as mycos is just sugar for import math mycos = math.cos But don't teach them this: > |from math import * There's no reason for beginners to use wildcard imports until they've mastered *not* using wildcard imports. -- Steve “Cheer up,” they said, “things could be worse.” So I cheered up, and sure enough, things got worse. -- https://mail.python.org/mailman/listinfo/python-list
