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Implicit type conversion?

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
react
Domain
frontend

Research direction

Start with the ReactEvent.Form.target(evt)["value"] expression and the useState setter in the supplied component, then reproduce the behavior using the linked Playground. Compare the result with the linked forum thread and determine whether the inferred type is intentional; done means the behavior is clarified or a concrete repository change is identified.

Written by the indexing model from the issue text.

Description

Hello,
I’m exploring rescript-react and noticed a peculiar behaviour. Here’s my test code:

module MyComponent = {
  @react.component
  let make = () => {
    let (value, setValue) = React.useState(_ => 0)
    <>
      <div> {React.string(string_of_int(value))} </div>
      <input
        onChange={evt => {
          let x = ReactEvent.Form.target(evt)["value"] // 1
          setValue(_ => x) // 2
        }}
      />
    </>
  }
}

What I noticed is that on the line marked with // 1 the type of x is 'a, but on line // 2 hovering over x shows the type int. Why is that? I would expect the compiler to ask me to decode the value of x.

Thank you in advance!

P.S.

Dominant language
ReScript
Stars
517
Forks
45
PR merge metrics
No merged PRs in 30d

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