break array of objects into separate arrays based on a property

Question

Say I have an array like this:

var arr = [
    {type:\"orange\", title:\"First\"},
    {type:\"orange\", title:\"Second\"},
    {type:\"banana\", title:\"Thi         


        

Answer 1

Typescript version.

/**
* Group object array by property
 * Example, groupBy(array, ( x: Props ) => x.id );
 * @param array
 * @param property
 */
export const groupBy = (array: Array, property: (x: T) => string): { [key: string]: Array } =>
  array.reduce((memo: { [key: string]: Array }, x: T) => {
    if (!memo[property(x)]) {
      memo[property(x)] = [];
    }
    memo[property(x)].push(x);
    return memo;
  }, {});

export default groupBy;