Is this pythonic?

[Steve D'Aprano]

On Wed, 23 Nov 2016 10:11 pm, Frank Millman wrote:

> Gah! The law of unintended consequences strikes again!
> 
> As I mentioned, the class in question represents a database column. 

Yes, you mentioned that.

> A 
> separate class represents a database row. I have a __str__() method on the
> 'row' class that prints a nicely formatted representation of the object
> with all of its column objects and their values.

You didn't mention that, but it shouldn't matter.

 
> With the above changes, I had to turn getval() into a coroutine.

You what?

I'm gobsmacked by this assertion. Nobody else seems to have commented on
this, so perhaps I'm missing something, but this strikes me as astonishing.
Nothing in your earlier post even hinted that you were using coroutines or
async, and as sure as the day is long memoisation doesn't force you to
start.

Even if the computation of the memoised value is done asynchronously, you
can easily split the computation off to a separate method (as you already
talked about doing!) and make getval() block until it returns.


[...]
> I can say 'print(await obj.__str__())', and it works, but I lose the
> ability to include it in a larger print statement.

Any time you find yourself directly calling dunder methods, you're probably
doing it wrong. This is one of those times.




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