What could be improved here?
Is it better for be to be a string ?
const valueGetter = <T extends {value:V}, V>(o:T) => ():V => o.value
const myValueGetter = valueGetter({x:1, value:'a string'}) // const myValueGetter: () => {}
const be = myValueGetter() // const be: {}
It is puzzling why TypeScript fails to recognize the relationship between V and the type of value in T.
In instances like this, it proves beneficial to explicitly state that the desired type is derived from a member type within T:
const valueExtractor = <T extends {value: V}, V>(obj: T) => ((): T['value'] => obj.value)
const myValueExtractor = valueExtractor({num:1, value:'abc'}) // const myValueExtractor: () => string
const extracted = myValueExtractor() // const extracted: string
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