freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/manipulate-arrays-with-pop.md

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id title challengeType videoUrl forumTopicId dashedName
56bbb991ad1ed5201cd392cc Manipulate Arrays With pop() 1 https://scrimba.com/c/cRbVZAB 18236 manipulate-arrays-with-pop

--description--

Another way to change the data in an array is with the .pop() function.

.pop() is used to pop a value off of the end of an array. We can store this popped off value by assigning it to a variable. In other words, .pop() removes the last element from an array and returns that element.

Any type of entry can be popped off of an array - numbers, strings, even nested arrays.

var threeArr = [1, 4, 6];
var oneDown = threeArr.pop();
console.log(oneDown);
console.log(threeArr);

The first console.log will display the value 6, and the second will display the value [1, 4].

--instructions--

Use the .pop() function to remove the last item from myArray, assigning the popped off value to removedFromMyArray.

--hints--

myArray should only contain [["John", 23]].

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

You should use pop() on myArray.

assert(/removedFromMyArray\s*=\s*myArray\s*.\s*pop\s*(\s*)/.test(code));

removedFromMyArray should only contain ["cat", 2].

assert(
  (function (d) {
    if (d[0] == 'cat' && d[1] === 2 && d[2] == undefined) {
      return true;
    } else {
      return false;
    }
  })(removedFromMyArray)
);

--seed--

--after-user-code--

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

--seed-contents--

// Setup
var myArray = [["John", 23], ["cat", 2]];

// Only change code below this line
var removedFromMyArray;

--solutions--

var myArray = [["John", 23], ["cat", 2]];
var removedFromMyArray = myArray.pop();