Feat: add keyOf type

[hinkik]

Adds a KeyOf type that can be used like this

myObject = {
  foo: "bar",
  4: "foobar",
}

const keyOfObjectSchema = ft.KeyOf("nameOfMyObjectKeys", myObject)

Potential issue: Object.Keys(...) returns string[] and thus other types than string keys become degenerated which means that

keyOfObjectSchema.parse("4") // "4"

even though "4" is not a member of keyof typeof myObject. Furthermore, other types that are not number will always fail the parsing.

Since all js object fields becomes strings, perhaps one needs to enforce the keys to be strings in the first place?

[rollingversions[bot]]

Change Log for funtypes (4.1.0 → 4.2.0)

New Features

• Added KeyOf(SomeObject) codec to match keyof typeof SomeObject

Edit changelog