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Created by utrain on 11/4/2024 in #support
How to make setStore treat a class/interface as an opaque value instead of a partiable one?
So, I'm currently using a UOM library called @buge/ts-units. It has this interface called Quantity that I want to use in my stores. For example: 
type Rectangle = {
  // Length is an instance of Quanity
  // Length = Quantity<...>
  width: Length 
  height: Length
}
type Rectangle = {
  // Length is an instance of Quanity
  // Length = Quantity<...>
  width: Length 
  height: Length
}
The problem is that whenever I want to use setStore with the path syntax, this is allowed: 
// No errors:
setRectangleStore("width", 0)

// function inches(length: number): Length
// It should only allow:
setRectangleStore("width", inches(0))
// No errors:
setRectangleStore("width", 0)

// function inches(length: number): Length
// It should only allow:
setRectangleStore("width", inches(0))
It seems to be because in Typescript, the type used for the last argument is Partial<Length>, which allows a number(???) to be accepted. Ignoring that, I would want to treat Length as a opaque, unpatchable, immutable value just like any other primitive type (boolean, number, bigint, et cetera). The work around I found is essentially avoiding the path syntax and merge at the top-level: 
// Good
setRectangleStore({ width: inches(0) })

// Errors as expected:
setRectangleStore({ width: 0 })
// Good
setRectangleStore({ width: inches(0) })

// Errors as expected:
setRectangleStore({ width: 0 })
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