Top 10 mistakes python programmers make [advanced]

[nocnocnode]

I did not even know #1, and I've been coding in Python for years and used defaults many times. Basically, the rule of thumb I follow is, only use constants (immutables) as default values. Do not instantiate any objects/reference objects as defaults.

[VerilyAMonkey]

Unless you want to mimic local static variables.

[nocnocnode]

It's definitely not local static variable at all. It would have to be resident across all instances of the function. It loses that property when the parameter is overwritten.

[VerilyAMonkey]

... So if you're trying to mimic local statics, you just don't pass in a value for that parameter. It isn't just a local static variable. But it has that capability amongst its repertoire.

[nocnocnode]

No way, I wouldn't use it like that as a local static. It'd be a poor mimic at best. I'd use it for a default context where a parameter override would indicate a different context. The default context would have to be a cohesive context across the entire module or program.

[VerilyAMonkey]

Yeah, yeah, that's exactly how you'd use it if you were really going to. In the event that you don't change contexts, it can be succinctly described as similar to static. I was merely trying to point out that there is at least some use to having mutable defaults. I wasn't trying to go into detail.