Why can't I map the constructor `Some` over an Array?

1

The following code gives the error This variant constructor, Some, expects 1 argument; here, we've only found 0.

let xs = [1, 2, 3]
let optXs = Belt.Array.map(xs, Some)

But this feels like it should be right? Is there a way to do this without using a lambda function?

2

Variant constructors are not functions. So yes, you would need to define a function for this.

let xs = [1, 2, 3]
let some = x => Some(x)
let optXs = Belt.Array.map(xs, some)
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3

Too bad _ doesnt work here…Js.Array2.map(Some(_)) would be nice.

4

FWIW, there is also Js.Option.some

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