Typescript recursive types

Question

Just trying to get my head around creating typings for recursive data structures. Can anyone give any refinements on what should be done? i.e. currently linting complains if I set:

const graph: INestedGraph<typeof data> = data;

Any help would be massively appreciated!

interface INestedGraph<T> {
    name: string;
    position?: number[];
    children?: T[] extends INestedGraph<infer U>[] ? INestedGraph<U>[]: null[]; 
}

const data =  {
    name: "root",
    children: [
      {name: "child #1"},
      {name: "child #2",
        children: [
          {name: "grandchild #1",
            children: [{name: "great-grandChild#1"}]},
          {name: "grandchild #2"},
          {name: "grandchild #3"}
        ]
      }, 
      {name: 'child #3', 
        children: [
            {name: 'grandchild #6'}
        ]}
    ]
  };

Rubydesic · Accepted Answer · 2020-10-28 13:25:49Z

3

Can't you just do this?

interface INestedGraph {
    name: string;
    position?: number[];
    children?: INestedGraph[]
}

answered Oct 28, 2020 at 13:25

Rubydesic

3,51716 silver badges30 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Hector Crean Over a year ago

Definitely a good option. But I think there is some mechanism to limit the depth to which the data structure is searched to conform to the type. One of Typescript 4.0's new features seems to be 'recursive types' and was wondering if anyone had any knowledge on them.

Rubydesic Over a year ago

@HectorCrean what is your goal? You should put it in the question. You need a tree type that can only have a max depth?

Collectives™ on Stack Overflow

Typescript recursive types

1 Answer 1

2 Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Related