Array map function doesn't change elements

Question

In JavaScript, I have an array, which is

array = [true, false]

In some cases, I am trying to initialize this array

array.map(i         


        

Answer 1

If your mapping is simple, you can do:

var array = [true, false];
array = array.map(_ => false);

console.log(array);
// [false, false]

Answer 2

JavaScript Array map() Method

*)creates a new array with the results of calling a function for every array element and it calls the provided function once for each element in an array, in order.

Note: map() Method does not execute the function for array elements without values and it does not change the original array.

more details

Answer 3

.map() method is not mutable, check out its return value:

var arr2 = array.map(item => false)
console.log(arr2)

In functional programming, it's recommended that values do not change often, and JavaScript borrowed it. At least for .map() and .reduce() this is true. Make sure you know .map() well.

Answer 4

Array map function is working fine. The map() method creates a new array with the results of calling a provided function on every element in this array. map() does not mutate the array on which it is called.

var array = [true, false]



var new_array = array.map(function(item) {
  return false;
});

console.log(array)
console.log(new_array)