Question

I’ve recently found myself using the following pattern a lot:

x = 3
if this:
   this.process()
   if this.something:
       x = this.a_value

I don’t want to do this:

if this and (this.process() or True) and this.someting:
    x = this.a_value
else:
    x = 3

or this:

if this:
   this.process()
   if this.something:
       x = this.a_value
   else:
       x = 3
else:
    x = 3

but I can’t help but feel that setting the value and then changing it is a little messy, especially considering in some use cases the fallback value is seldom used.

Is there a better/tidier way?

Answer 1

I think of the three options you present, the first one, i.e., the one you are using, is the best. The code is clear and everyone will know what’s happening. I can’t think of a neater/tidier way, this is how I would code it too, based on the “Simple is better than complex.” principle

Re “I can’t help but feel that setting the value and then changing it is a little messy,” if you want a default value, there’s no way around setting one.

It certainly is much tidier than using the other two else approaches. Readability counts.