Implement Array.prototype.map. To avoid overwriting the actual Array.prototype.map
Question
Implement Array.prototype.map. To avoid overwriting the actual Array.prototype.map
Solution
Sure, here is a simple implementation of Array.prototype.map in JavaScript without overwriting the actual Array.prototype.map:
Array.prototype.myMap = function(callback) {
var arr = this; // get reference to the current array
var newArr = []; // create a new array to hold the results
for (var i = 0; i < arr.length; i++) {
newArr.push(callback(arr[i], i, arr)); // call the callback with the current element and its index, then push the result into the new array
}
return newArr; // return the new array
};
You can use this function like this:
var numbers = [1, 2, 3, 4, 5];
var squares = numbers.myMap(function(num) {
return num * num;
});
console.log(squares); // [1, 4, 9, 16, 25]
This code defines a new method on the Array prototype called myMap. This method takes a callback function as an argument, which it calls for each element in the array, just like the real Array.prototype.map method. The callback function is expected to return a new value for each element, which are collected into a new array that is returned by the myMap method.
Similar Questions
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