[kureikain]

I don't know Mint but want to give a data point about that.

The `=` is rebinding, what that mean is the original value doesn't change. If you pass that counter variable somewhere, it has its original value. the `count = counter + 1` here mean that a new memory block is allocated, get a value, and the `counter` in this scope is point to it. The old value in the original memory block won't change.

At least, that's the case of Erlang/Elixir.

[mikewarot]

That's horrible... and yet I see exactly why it is needed for multi-threaded, multi-core systems.

Question: When is it safe to throw the old value away?