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isSubsetWith

Checks if the subset array is entirely contained within the superset array.

This function takes two arrays and a comparison function as arguments. The comparison function is used to determine whether the elements are equal. The function returns true if all elements of the subset exist in the superset, and false otherwise.

Signature

typescript
function isSubsetWith<T>(superset: T[], subset: T[], areItemsEqual: (x: T, y: T) => boolean): boolean;

Parameters

  • superset (T[]): The array that may contain all elements of the subset.
  • subset (T[]): The array to check against the superset.
  • areItemsEqual ((x: T, y: T) => boolean): A function to determine if two items are equal.

Returns

(boolean): Returns true if all elements of the subset are present in the superset, otherwise returns false.

Examples

typescript
const superset = [{ id: 1 }, { id: 2 }, { id: 3 }];
const subset = [{ id: 2 }, { id: 1 }];
const areItemsEqual = (a, b) => a.id === b.id;

isSubsetWith(superset, subset, areItemsEqual);
// Return true

const superset = [{ id: 1 }, { id: 2 }, { id: 3 }];
const subset = [{ id: 4 }];
const areItemsEqual = (a, b) => a.id === b.id;

isSubsetWith(superset, subset, areItemsEqual);
// Return false

Released under the MIT License.