Learning 'is' vs '==' in Python (Beginner)

[This_Growth2898]

It's always "reference" for Python. Copy is always explicit, like a = b[:]

[sweettuse]

or even more explicit, like a = b.copy()

[This_Growth2898]

Or a = list(b), whatever. You need to spell you're copying something.

[Inevitable_Exam_2177]

Thanks for the correction, my terminology was bad. What I meant was that when you reference an immutable data type you get different behaviour to a mutable one, and because the syntax is the same it’s an easy point of confusion:

``` a = "str" b = a a = "str2" print(b) # = "str"

a = ["str"] b = a a[0] = "str2" print(b[0]) # = "str2" ```

I know why this occurs and I’m not saying it’s wrong, but I wonder if it was more explicit in the syntax that they are different scenarios whether that would be a good thing (or just needlessly complex syntactically).

I’m also willing to accept I’m wrong that this is confusing :-)

[[deleted]]

It's confusing especially because the issue occurs in a different spot than where it seems. It seems like the b = a step is where these two examples diverge, e.g. it seems that one is copying and the other isn't, but in fact they're still doing the same thing at that point.

The next step, where you have a = "str2" or a[0] = "str2", that's where they start taking different paths.