JavaScript: Create an object with keys generated by running the provided function for each key and the same values as the provided object

JavaScript fundamental (ES6 Syntax): Exercise-81 with Solution

Write a JavaScript program to create an object with keys generated by running the provided function for each key. The object will have the same values as the provided object.

• Use Object.keys() to iterate over the object's keys.
• Use Array.prototype.reduce() to create a new object with the same values and mapped keys using fn.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const mapKeys = (obj, fn) =>
  Object.keys(obj).reduce((acc, k) => {
    acc[fn(obj[k], k, obj)] = obj[k];
    return acc;
  }, {});
console.log(mapKeys({ a: 1, b: 2 }, (val, key) => key + val));

Sample Output:

{"a1":1,"b2":2}

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-81-1 by w3resource (@w3resource) on CodePen.

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