[Polygator]

The fundamental reason why many functional languages won't allow you to do the first is that they use immutable data structures.

We could indeed introduce syntactic sugar (`y= (x[0]:=10)` maybe), but you'll still need to introduce a new variable to hold the modified list.

[thrdbndndn]

It's my understanding that, at least in Python, you can't change immutable data type but you can just assign a new data to the same variable and therefore overwrite it, right? So even if JAX makes list type immutable, you can still just re-use `x` to save the new modified list.