generic type variable constraints in typescript

Question

I am looking for the equivalent of the following c# syntax for typescript

public abstract class PBaseHierarchical<T> : PBase where T : PBaseHierarchical<T>
    {
...
}

I only find the constraint "extends" which would be the following in typescript:

export abstract class PBaseHierarchical<T extends PBaseHierarchical<T>> extends PBase {
...
}

But from my understanding "extends" says that T should inherit from PBaseHierarchical. What I want is that T is of type PBaseHierarchical.

Thanks a lot for any help !

extends in type constraint is actually covers both: is of type PBaseHierarchical or "extends" PBaseHierarchical. Pretty much the same as where T : PBaseHierarchical in c# — Aleksey L.
– Aleksey L., Commented Mar 2, 2019 at 7:53
Hi Alekey - thanks for your feedback ! If you post your answer I could mark it as a such. — Fabianus
– Fabianus, Commented Mar 2, 2019 at 13:41

Aleksey L. · Accepted Answer · 2019-03-03 06:57:47Z

1

extends in type constraint is actually covers both:

T is of type PBaseHierarchical or T "extends" PBaseHierarchical

Pretty much the same as where T : PBaseHierarchical in C#.

Also pay attention that types are compared structurally in Typescript.

answered Mar 3, 2019 at 6:57

Aleksey L.

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