I know it's possible in JavaScript to swap two integer values with the XOR option, thus eliminating the need of a temporary variable:
a = 14; b = 27; a^=b; b^=a; a^=b;
// a == 27 and b == 14
But is there a similar no-temp technique in JavaScript for swapping strings?
ES6's new destructuring assignment syntax:
[a, b] = [b, a]
There is an universal single line swapping method that doesn't involve creating new temp variables, and uses only an "on-the-fly" array, here it is:
var a = "world", b = "hello";
b = [a, a = b][0];
console.log(a, b); // Hello world
Explanation:
a=b assigns the old value of b to a and yelds it, therefore [a, a=b] will be [a, b][0] operator yelds the first element of the array, which is a, so now b = [a,b][0] turns into b = aThen, for strings only, you can also do this:
var a = "world", b = "hello";
a = b + (b = a, "");
console.log(a, b); // Hello world
You can replace the "" with a 0 if you want to do this with numbers.
Explanation:
(b = a, "") assigns the old value of a to b and yelds an empty stringa = b + "", and since that b + "" === b, the old value of b is assigned to aAt this page you can find and run a benchmark of different swapping methods. The result of course varies between browser and JS engine versions.
Here comes a ES6 solution
We can do the Destructuring Assignment and swap like a boss.
var a = "Hello", b = "World!";
console.log(a, b); // Hello World!
[a, b] = [b, a]; //
console.log(a, b); // World! Hello
We can use string replace() method to achieve this!
By using regular expression: "/(\w+)\s(\w+)/"
const name = "Akash Barsagadey";
const swapName = name.replace(/(\w+)\s(\w+)/, "$2 $1");
console.log(swapName); //Barsagadey Akash
