Microsoft/TypeScript

Services for non-homomorphic mapped type

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#25.607 geöffnet am 12.07.2018

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Domain: LS: Symbol NavigationDomain: Mapped TypesExperience EnhancementHelp WantedSuggestion

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Beschreibung

TypeScript Version: 3.0.0-dev.20180712

Code

interface I {
 a: number;
 b: number;
}
type J = { [K in "b"]: I[K] };
declare const j: J;
j.b; // Go-to-definition does not work

Expected behavior:

Since the type we're getting is I[K], the mapped property symbol should have a reference back to the corresponding property in I.

Actual behavior:

The mapped type creates an unrelated property symbol and services don't work.

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