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re: Function vs Object VIEW POST

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re: From what I understood, the main complaint against stateful closures (would that be what you call them) is when you provide it with the same inputs...

Closure without mutation or re-assignment ("pure"):

const addSome = (x) => (y) => x + y;
const addFive = addSome(5);
addFive(1) === addFive(1) 

Closure with re-assignment += ("not pure"):

const counter = (x) => (y) => x += y;
const countFromZero = counter(0);
countFromZero(1) !== countFromZero(1)

My point is that there is nothing wrong with closures. It is re-assignment and mutation which make closures (or functions) "not pure".

Re state: in pure FP I think we mean a "named" piece of data whose instances get changed over time:

go :: Int -> Int
go 0 = 0
go s = s + go (s-1)

Here s can be thought of as state, even though specific bindings of s don't change.

We observe state over the course of computation.

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