core.dereference

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Dereference type

Given a type Reference<X>, extracts X

The input is constrained to references, so passing anything else is a compile error rather than a silently unhelpful type. null and undefined are allowed and pass through, so an optional reference field dereferences to an optional resource.

The check is structural, though: this accepts anything assignable to Reference, an interface whose fields are all optional. Object types that are not true references are therefore accepted, and with no resource property to infer from, resolve to Resource, the default type argument of Reference.

Signature:

export type Dereference<T extends Reference | null | undefined> = T extends Reference<infer R> ? R : T;