Javascript syntax errors with basic expressions

Questions & Answers
1

The error I get is

Scripts/Gamble.js(17,23): BCE0044: expecting ), found ‘=’.

if I double up that equals sign I get

Scripts/Gamble.js(13,18): BCE0034: Expressions in statements must only be executed for their side-effects.

var balance : float = 0.0;
var payOut : float = 0.0;
var betAmount : float = 100.0;
var profitOnWin : float = 0.0;
var rollUnderToWin : float = 0.0;
var diceNumber : float = 50.0;
var totalWin : float = 0.0;
public var winChance : float = 0.0;

function FixedUpdate (){
	totalWin == payOut*betAmount;
	profitOnWin == totalWin-betAmount;
	rollUnderToWin == winChance;
	
	if (winChance == 50.0){
	 	payOut == 1.98;
	 	}
	if (winChance == 25.0){
	 	payOut == 3.96;
	 	}
	if (winChance == 10.0){
	 	payOut == 9.9;
	 	}
	 //
	//if button press, call function DiceRoll
}

function DiceRoll (){
	diceNumber == Random.Range(0.0,100.0);
	if (diceNumber <= winChance){
		GUI.Label(screenRect, "You Win!");
		//add profit to balance
		balance+=profitOnWin;
		}
	if (diceNumber >= winChance){
		GUI.Label(screenRect, "You Lose!");
		//subtract betAmount from balance
		balance-=betAmount;
		}
}

I have no idea what I’m doing wrong with the syntax here, I’ve been making adjustments for hours and can’t get it.

2

Hello,

There is one key thing wrong in your script, but before I get to that, there are a couple other things I should mention:

The indentation level of open { and closed } should be the same:

if (comparison) {
}
//NOT
if (comparison) {
    }

Absolutely everyone is in agreement, that you should leave a space between ) and {:

if (comparison) {
//OR
if ( comparison ) {
//BUT NEVER
if(comparison){

Now onto the actual problem:

In UnityScript, just like in C#, there are different types of operators, such as x.y or < etc. These are all about using special syntax to achieve certain things.

There are primary:

//Member access with the "." operator
x.y
//Invoke methods
f(x)
//Type casting
x as y
//increasing using the increment operator
x++
//Getting the size of the object
sizeof(x)

There are the Unary:

//Positive
+x
//Negative
-x
//Not
!x
//Increment
++x
//Decrement
--x

There are the multiplicative:

//Multiply
x*y
//Divide
x/y
//Mod
x%y

Additive:

//Addition
x + y
//Subtraction
x - y

Shift:

//Right Shift
x >> y
//Left Shift
x << y

Relation:

//Larger Than
x > y
//Smaller Than
x < y
//With equals
x >= y
x <= y
//Type checking
x is y

Equality:

//Are Equal
x == y
//Are Not Equal
x != y

Logical:

//And
x & y
//Or
x | y
//XOr
x ^ y

Conditional:

//And
x && y
//Or
x || y

Assignment:

//Assign to
x = y
//Add do
x += y
//Subtract from
x -= y
//Multiply py
x *= y
//Divide by
x /= y
//lots more

All of this information can be found here and although it’s a C# reference, UnityScript has most of the basic operators too.

Now lets look at the line where your error occurs and lets see which operator you are using:

rollUnderToWin == winChance;
 
if (winChance == 50.0){

So the first line you are doing a comparison between rollUnderToWin and winChance and then later you do a comparison between winChance and 50.0 to check if they are equal. Why are you doing a comparison in the first one? Does that make any sense?

Lets look at what happens when we use a single =:

rollUnderToWin = winChance;
 
if (winChance = 50.0){

First we assign winChance to rollUnderToWin and then we check, we assign (WTF) winChance the value of 50.0… That doesn’t make any sense does it?

I think from this you should be able to figure out what you need to do to make it work.

Hope this helps,
Benproductions1

3

You would never use == when you are assigning values to a variable; that’s only for comparing two values. == for comparison, = for assignment.