Create object with keys from an array of strings and values that are an array containing a specific string from the `key array`.

createObjectUsingArrays.js

/*
* -----------------------------------------------------------------------------------------
* ==== End goal is to have an object, `myObject` look like this:  =========================
* -----------------------------------------------------------------------------------------
*   myObject: {
*     'firstKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-firstKey'],
*     'secondKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-secondKey'],
*     'thirdKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-thirdKey']
*   }
*/
const myObject = {};
const objectKeyNamesArray = ['firstKey', 'secondKey', 'thirdKey'];
const objectValuesArray = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];

objectKeyNamesArray.map(function(arrayValue) {
  // ==== Copy of `objectValuesArray`.
  // ** Purpose: Allows for the manipulation of values in `objectValuesArray`
  //              without affecting the original array or other key-values.
  // !! `.slice(0)` allows us to create the copy.
  // ----
  // Current State (first iteration)
  // >> myObject = {};
  // >> objectValuesArray = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  // >> copy = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  const copy = objectValuesArray.slice(0);
  
  // ==== Custom value dependent on `arrayValue`.
  // ----
  // Current State (first iteration)
  // >> myObject = {};
  // >> objectValuesArray = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  // >> copy = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  // >> custom = 'value-firstKey';
  const custom = 'value-' + arrayValue;
  
  // ==== Insert, or `push`, the `custom` value into `copy` array.
  // ----
  // Current State (first iteration)
  // >> myObject = {};
  // >> objectValuesArray = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  // >> copy = ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-firstKey'];
  // >> custom = 'value-firstKey';
  copy.push(custom);
  
  // ==== Create a key for `myObject` using the current `arrayValue` with a value of `copy`
  // ----
  // Current State (first iteration)
  // >> myObject = {
  //      'firstKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-firstKey']
  //    };
  // >> objectValuesArray = ['valueOne', 'valueTwo', 'valueThree', 'valueFour'];
  // >> copy = ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-firstKey'];
  // >> custom = 'value-firstKey';
  myObject[arrayValue] = copy;
});



// ==== Check the output
// + Actual ouput is our desired ouput!   :)
/*
* myObject: {
*   'firstKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-firstKey'],
*   'secondKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-secondKey'],
*   'thirdKey': ['valueOne', 'valueTwo', 'valueThree', 'valueFour', 'value-thirdKey']
* }
*/
console.log(myObject);