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Discussion on: Type | Treat Challenge 2

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Replies for: In the advanced/intermediate challenge. It states that 'Bobby Tables' cannot have peanuts but to me, the solution seems to do the opposite and actu...

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dungdung profile image
Houston • 
type AllCandies = Extract<ResultsFromHalloween, {candy: true}>;
type AllTricks = Extract<ResultsFromHalloween, {trick: true}>;
type AllCandiesWithoutPeanuts = Exclude<AllCandies, {peanuts: true}>;
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John Cheng • • Edited

I agree with your implementation. I was discussing the solution provided in this post :)
Maybe @gcrev93 can help me if I misinterpreted it

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Houston •

My bad, should have said something instead of just plopping down a solution - yes you are correct saying that:

type AllCandiesWithoutPeanuts = HasPeanuts<AllCandies>
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is the opposite of the solution. Something more correct would have the inverted type. I'm not sure how one would go from HasPeanuts to something like OmitsPeanuts but declaring it from scratch is straightforward:

type OmitsPeanuts<A> = A extends { peanuts: true } ? never : A;
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