Function intersection

intersection<K, KM extends Primitive>(
a: ISetMapped<K, KM>,
b: ISetMapped<K, KM>,
): ISetMapped<K, KM>

Computes the intersection of two ISetMapped instances.

Type Parameters

K
The type of the elements.
KM extends Primitive
The type of the mapped keys.

Parameters

a: ISetMapped<K, KM>
The first set.
b: ISetMapped<K, KM>
The second set.

Returns ISetMapped<K, KM>

A new ISetMapped instance representing the intersection.

Example

type Point = Readonly<{ x: number; tag: string }>;

const toKey = (point: Point) => JSON.stringify(point);

// eslint-disable-next-line total-functions/no-unsafe-type-assertion
const fromKey = (key: string) => JSON.parse(key) as Point;

const left = ISetMapped.create<Point, string>(
  [
    { x: 1, tag: 'a' },
    { x: 2, tag: 'b' },
  ],
  toKey,
  fromKey,
);
const right = ISetMapped.create<Point, string>(
  [{ x: 2, tag: 'b' }],
  toKey,
  fromKey,
);

const overlap = ISetMapped.intersection(left, right);

assert.deepStrictEqual(Array.from(overlap), [{ x: 2, tag: 'b' }]);