Passed generic not giving exact return type in callbacks about typescript HOT 7 CLOSED

It's probably time for my once-every-few-years attempt to look at #241 again and see what doesn't work these days

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@essenmitsosse That is working as intended. The type of your variables inferred to { foo: string; bar: string } due to the lack of type annotation, and when returning the value the compiler only checks compatibility. { foo: string; bar: string } is compatible with the type { foo: string }.

See the FAQ entry: (Indirect) Excess Properties Are OK

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This is essentially a duplicate of #241. Check the linked issues.

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Thanks for the reference @MartinJohns! My "Excess property checks on return types" search did not hit "widen return types" it seems 😂

But okay, great. I also see there was a design discussion on this #56965.

It seems it is planned to be fixed, hm

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Okay, so I get a response that the referenced discussion (#56965) is related, but not a fix for this issue. So yeah, not sure how much attention this deserves and how to ensure it gets that deserved attention 🤔

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Not sure if this is considered related, but this also doesn't work:

cbFunc<MyType>((): MyType => {
    const value = {
        foo: 'bar',
        bar: 'baz'
    }
    
    return value
})

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This issue has been marked as "Duplicate" and has seen no recent activity. It has been automatically closed for house-keeping purposes.

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