Toggling between Boolean variable

Question

I'm wondering how you would toggle between two boolean variables. This works correctly the first time running the code but then after running it a second time the output isn't correct.

Output first time running switchPlayer():

player1.isActive = false,
player2.isActive = true

Output second time running switchPlayer():

player1.isActive = true,
player2.isActive = true

Below is the code I wrote:

var Player = function(score, isActive){
  this.score = score;
  this.isActive = isActive;
}

Player.prototype.toggleIsActive = function(){
      if(this.isActive === false){
        this.isActive = true;
      } else{
        this.isActive = false;
      }
    }

function switchPlayer(){
  if(player1.isActive === true){
    player1.toggleIsActive();
    player2.toggleIsActive();
  } else{
    player1.isActive = true;
  }
}
var player1 = new Player("0", true);
var player2 = new Player("0", false);

switchPlayer();
switchPlayer();

user_560299 · Answer

You can simplify it like this:

Player.prototype.toggleIsActive = function(){
   this.isActive = !this.isActive;
}

function switchPlayer(){
    player1.toggleIsActive();
    player2.toggleIsActive();
}

ToggleIsActive should just be the opposite of what it once was. Also note that switchPlayer only calls toggle with no specific logic.

user_8526705 · Answer

You can achieve this by removing the if/else from the switchPlayer() implementation:

function switchPlayer(){

  player1.toggleIsActive();
  player2.toggleIsActive();

}

Also, consider simplifying your toggleIsActive() method on the Player prototype like so:

Player.prototype.toggleIsActive = function(){
   this.isActive = !this.isActive;
}

Here's a full example:

var Player = function(score, isActive){
  this.score = score;
  this.isActive = isActive;
}

Player.prototype.toggleIsActive = function(){
   this.isActive = !this.isActive;
}

function switchPlayer(){

  player1.toggleIsActive();
  player2.toggleIsActive();
  
}
var player1 = new Player("0", true);
var player2 = new Player("0", false);

console.log('player1.isActive', player1.isActive)
console.log('player2.isActive', player2.isActive)
console.log('----------------')

switchPlayer();

console.log('player1.isActive', player1.isActive)
console.log('player2.isActive', player2.isActive)
console.log('----------------')

switchPlayer();

console.log('player1.isActive', player1.isActive)
console.log('player2.isActive', player2.isActive)
console.log('----------------')

user_3234 · Answer

let player1 = {};
let player2 = {};

player1.isActive = false;
player2.isActive = true;

function toggle () {
  player1.isActive = !player1.isActive;
  player2.isActive = !player2.isActive;
  
  console.log('player1', player1.isActive, 'player2', player2.isActive);
}

Toggling between Boolean variable

3 Answers