I cant seem to return the result of inside the function

Question

I have created a basic rock paper scissors game and i cannot return the result inside the function.

I've been try everything

link console logging the compare and also putting it inside a variable..

console.log(compare) returns undefined for some reason.

Please help

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
var result;

if (computerChoice < 0.34) {
 computerChoice = "rock";
} else if(computerChoice <= 0.67) {
 computerChoice = "paper";
} else {
 computerChoice = "scissors";
} console.log("Computer's choice: " + computerChoice);
  console.log("Your choice: " + userChoice);
  console.log(computerChoice + " vs " + userChoice); 
  

var compare = function(userChoice, computerChoice){
    if (userChoice === computerChoice){
        return    "The result is a tie!"; 
    } else if (userChoice ==="rock"){
       if(computerChoice ==="scissors"){
        return "rock wins!";    
       }
       else {
         return "paper wins!";       
       }
    } else if (userChoice === "paper") {
        if(computerChoice === "rock") {
        return "paper wins!"; 
        }
        else {
        return "scissors wins!";
        }
    } else if (userChoice === "scissors") {
        if(computerChoice === "rock") {
        return "rock wins!"; 
        }
        else {
        return "scissors wins!";
        }
    }
     
}

oh that was an honest typo but having it removed, I stil have the same problem — Redondo Velasco, Jul 24 '17 at 10:35
Well I tested the snippet and it works fine. I think you believe it doesn't return anything because you don't do anything with the returned string — Shinra tensei, Jul 24 '17 at 10:37
@Shinratensei so maybe my problem is how can i actually display that returned string? — Redondo Velasco, Jul 24 '17 at 10:39
well, `compare` stores the string returned by the function, so just `console.log(compare);` at the end maybe? Try but I'm not sure, I don't know javascript — Shinra tensei, Jul 24 '17 at 10:41
@Shinratensei I've tried that already but it returns undefined! — Redondo Velasco, Jul 24 '17 at 10:42
you can make compare a function and then `alert(compare(userChoice,computerChoice))` — Colin, Jul 24 '17 at 10:43
never mind.. you have to make it "function compare (userChoice, computerChoice);" thanks for the help! — Redondo Velasco, Jul 24 '17 at 10:51
It is a variable that is a function. I don't know the diference to be honest. Look at my snippet in my answer. I changed it and it works. — Colin, Jul 24 '17 at 10:51
That function is wrong for that what you want. U can write like function compare(comp, user){ ... } and call console.log(compare(comp,user)) or if u want to store to variable, u can first write var Compare = compare(comp,user); than console.log(Compare); — Deathmras, Jul 24 '17 at 10:51
Here is the difference explained: https://stackoverflow.com/questions/4314434/difference-between-var-foo-function-and-function-foo — Colin, Jul 24 '17 at 10:52
@RedondoVelasco you see, that was an anonymous function. Basically, functions are objects in javascript and as such, variables can store them. They're different from other functions, I recommend reading this http://helephant.com/2008/08/23/javascript-anonymous-functions/ — Shinra tensei, Jul 24 '17 at 10:55

score 2 · Answer 1 · answered Jul 24 '17 at 10:55

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
var result;

if (computerChoice < 0.34) {
 computerChoice = "rock";
} else if(computerChoice <= 0.67) {
 computerChoice = "paper";
} else {
 computerChoice = "scissors";
} console.log("Computer's choice: " + computerChoice);
  console.log("Your choice: " + userChoice);
  console.log(computerChoice + " vs " + userChoice); 

function compare(userChoice, computerChoice){
    if (userChoice === computerChoice){
        return    "The result is a tie!"; 
    } else if (userChoice ==="rock"){
       if(computerChoice ==="scissors"){
        return "rock wins!";    
       }
       else {
         return "paper wins!";       
       }
    } else if (userChoice === "paper") {
        if(computerChoice === "rock") {
        return "paper wins!"; 
        }
        else {
        return "scissors wins!";
        }
    } else if (userChoice === "scissors") {
        if(computerChoice === "rock") {
        return "rock wins!"; 
        }
        else {
        return "scissors wins!";
        }
    }
     
}
var Compare = compare(userChoice, computerChoice);
console.log(Compare);

But if you want actually same code like u did there, u can use something like var compare = (function(comp,user){ ... })() — Deathmras, Jul 24 '17 at 10:57

score 0 · Answer 2 · answered Jul 24 '17 at 10:35

0

You have syntax error here...

return  =  "The result is a tie!";

change this to:

return "The result is a tie!";

answered Jul 24 '17 at 10:35

Pommesloch

492
5
17

That was an honest typo. But actually I'm still having the same problem! maybe because i cant console log the right value? – Redondo Velasco Jul 24 '17 at 10:38
@RedondoVelasco you need to call `compare();`at the bottom of your code for display the return statement. Otherwise you can just `console.log()`the string. – Pommesloch Jul 24 '17 at 10:46

Colin · Answer 3 · 2017-07-24T10:42:00.780

As Shinra tensei mentioned you had a = in line 18 that caused an error. Here is a updated snipped. I also added an alert for the compare function.

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
var result;

if (computerChoice < 0.34) {
 computerChoice = "rock";
} else if(computerChoice <= 0.67) {
 computerChoice = "paper";
} else {
 computerChoice = "scissors";
} console.log("Computer's choice: " + computerChoice);
  console.log("Your choice: " + userChoice);
  console.log(computerChoice + " vs " + userChoice); 
  
  alert(compare(userChoice,computerChoice));

 function compare (userChoice, computerChoice){
    if (userChoice === computerChoice){
        return  "The result is a tie!"; 
    } else if (userChoice ==="rock"){
       if(computerChoice ==="scissors"){
        return "rock wins!";    
       }
       else {
         return "paper wins!";       
       }
    } else if (userChoice === "paper") {
        if(computerChoice === "rock") {
        return "paper wins!"; 
        }
        else {
        return "scissors wins!";
        }
    } else if (userChoice === "scissors") {
        if(computerChoice === "rock") {
        return "rock wins!"; 
        }
        else {
        return "scissors wins!";
        }
    }
     
}

Shinra tensei · Answer 4 · 2017-07-24T10:57:06.047

The main problem here is that you never executed the anonymous function you wrote. I made compare a normal function instead of an anonymous one, just to make it more similar to other languages. This is a good working code:

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
var result;

if (computerChoice < 0.34) {
    computerChoice = "rock";
} else if(computerChoice <= 0.67) {
    computerChoice = "paper";
} else {
    computerChoice = "scissors";
} console.log("Computer's choice: " + computerChoice);
  console.log("Your choice: " + userChoice);
  console.log(computerChoice + " vs " + userChoice); 


function compare(userChoice, computerChoice){
    if (userChoice === computerChoice){
        return    "The result is a tie!"; 
    } else if (userChoice ==="rock"){
       if(computerChoice ==="scissors"){
        return "rock wins!";    
       }
       else {
         return "paper wins!";       
       }
    } else if (userChoice === "paper") {
        if(computerChoice === "rock") {
        return "paper wins!"; 
        }
        else {
        return "scissors wins!";
        }
    } else if (userChoice === "scissors") {
        if(computerChoice === "rock") {
        return "rock wins!"; 
        }
        else {
        return "scissors wins!";
        }
    }

}
console.log(compare(userChoice, computerChoice));

I cant seem to return the result of inside the function

4 Answers4