Option type required after open Belt

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1

Hello, I am a little confused with what I see (using the playground).

let x = ["a", "b", "c"]
let y = x[2] ++ " hi"

That compiles without error. After adding open Belt:

open Belt
let x = ["a", "b", "c"]
let y = x[2] ++ " hi"

I get the error:

[E] Line 3, column 8:
This has type: option<string>
Somewhere wanted: string

What changes?

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2

Accessing index of an array with Belt library returns an optional.

3

The Belt library is already there in the first example. What does “open Belt” do that it changes the behaviour of indexed access?

4

It brings another definition of Array.get into scope. x[2] is just syntax sugar for Array.get(x, 2).

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