freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/manipulate-arrays-with-shift.md

id, title, challengeType, videoUrl, forumTopicId, dashedName

id	title	challengeType	videoUrl	forumTopicId	dashedName
56bbb991ad1ed5201cd392cd	Manipulate Arrays With shift()	1	https://scrimba.com/c/cRbVETW	18238	manipulate-arrays-with-shift

--description--

pop() always removes the last element of an array. What if you want to remove the first?

That's where .shift() comes in. It works just like .pop(), except it removes the first element instead of the last.

Example:

const ourArray = ["Stimpson", "J", ["cat"]];
const removedFromOurArray = ourArray.shift();

removedFromOurArray would have a value of the string Stimpson, and ourArray would have ["J", ["cat"]].

--instructions--

Use the .shift() function to remove the first item from myArray and assign the "shifted off" value to a new variable, removedFromMyArray.

--hints--

myArray should now equal [["dog", 3]].

assert(
  (function (d) {
    if (d[0][0] == 'dog' && d[0][1] === 3 && d[1] == undefined) {
      return true;
    } else {
      return false;
    }
  })(myArray)
);

removedFromMyArray should contain ["John", 23].

assert(
  (function (d) {
    if (
      d[0] == 'John' &&
      d[1] === 23 &&
      typeof removedFromMyArray === 'object'
    ) {
      return true;
    } else {
      return false;
    }
  })(removedFromMyArray)
);

--seed--

--after-user-code--

if (typeof removedFromMyArray !== 'undefined') (function(y, z){return 'myArray = ' + JSON.stringify(y) + ' & removedFromMyArray = ' + JSON.stringify(z);})(myArray, removedFromMyArray);

--seed-contents--

// Setup
const myArray = [["John", 23], ["dog", 3]];

// Only change code below this line

--solutions--

const myArray = [["John", 23], ["dog", 3]];

// Only change code below this line
const removedFromMyArray = myArray.shift();