How to extend an existing JavaScript array with another array, without creating a new array

Question

There doesn\'t seem to be a way to extend an existing JavaScript array with another array, i.e. to emulate Python\'s extend method.

I want to achieve th

Answer 1

Another solution to merge more than two arrays

var a = [1, 2],
    b = [3, 4, 5],
    c = [6, 7];

// Merge the contents of multiple arrays together into the first array
var mergeArrays = function() {
 var i, len = arguments.length;
 if (len > 1) {
  for (i = 1; i < len; i++) {
    arguments[0].push.apply(arguments[0], arguments[i]);
  }
 }
};

Then call and print as:

mergeArrays(a, b, c);
console.log(a)

Output will be: Array [1, 2, 3, 4, 5, 6, 7]