newb question about @property

[Steve D'Aprano]

On Sun, 1 Oct 2017 05:46 pm, Bill wrote:

> If you were going to show non-Python users, say science undergraduates
> and faculty, that Python is an interesting tool (in 45 minutes), would
> one delve into descriptors? 

Hell no :-)

I think there's a hierarchy of difficulty/complexity/mind-bogglingness in
Python. From least complex to most:

- Using Python in an imperative fashion, as in simple scripts.

- Writing your own functions.

- Writing your own classes.

- Writing generators.

- Using decorators, including property.

- Writing your own decorators.

- Writing your own descriptors.

- Writing your own metaclasses (a.k.a. "the killer joke").

I wouldn't touch the last three in a beginner's class, not unless they already
had a significant amount of programming experience.



> I am thinking maybe. Here is what I am 
> thinking at this moment: trivial applications (probably), list
> comprehensions (definitely), generators (maybe briefly). Whatever I 
> would discuss, I think ending with descriptors could be a strong finish.

That depends on whether your aim is to confuse them or not :-)

I don't think the descriptor protocol is something you'll be able to explain in
five or ten minutes. *Using* descriptors like property, sure, that's fine.


> But I'm certainly not merely interested for the sake of my talk, I
> obtain some satisfaction in learning how things work.  If you can
> suggest any references for descriptors which you think are good, I would
> be interested.

The definitive explanation of descriptors is here:

https://docs.python.org/3/howto/descriptor.html



-- 
Steve
“Cheer up,” they said, “things could be worse.” So I cheered up, and sure
enough, things got worse.