ActionScript Custom Class With Return Type?

Question

i just know this is a dumb question, so excuse me in advance.

i want to essentially classify a simple function in it's own .as file. the function compares integers. but i don't know how to call the class and receive a boolean return.

here's my class

package
{
public class CompareInts
    {
    public function CompareInts(small:int, big:int)
        {
        compare(small, big);
        }

    private function compare(small:int, big:int):Boolean
        {
        if (small < big)
            return true;
            else
            return false;
        }
    }
}

so now i'd like to write something like this:

if (CompareInts(1, 5) == true). or output 'true' by writing trace(CompareInts(1, 5));

Answer 1

You have 2 options:

1) Make your compare function public and static.

static public function compare(small:int,big:int):Boolean {
{
    if (small < big)
        return true;
    else
        return false;
    }
}

And call it:

CompareInts.compare(1,5);

2) You don't actually need a class. You can just use a function. As long as there's only one public definition per AS file, you'll be fine (by that I mean that at the "top" level you can have a public class, an interface, a public function, a public var or a public namespace. It won't work if you try to have more than one.

package {
    public function compare(small:int,big:int):Boolean {
    {
        if (small < big)
            return true;
        else
            return false;
    }
}

Or, you could inline this into a single line and ditch the class / function entirely (parens are not neccesary, I just added them for clarity):

var compare:Boolean = (small < big);

Answer 2

• You are creating a Class and then function that are members of that Class so for calling them you have to instanciate the Class and then call the function of the instance created.

• Also CompareInts is the constructor of the class it can't return anything

the working code corresponding to your class will be:

package {
 public class CompareInts {

    public function CompareInts(){}

    public function compare(small:int, big:int):Boolean {
        if (small < big)
            return true;
            else
            return false;
    }
 }
} 

new CompareInts().compare(1, 2);

But this a litle bit overkill so what you can do is create a static function into your class and then call it directly without the needed to instanciate the class.

package {
 public class Compare {
    public static function compareInts(small:int, big:int):Boolean {
        if (small < big)
            return true;
            else
            return false;
    }
 }
} 

Compare.compareInts(1, 2)

If you don't want to group more functions into a Class you can always declare a single function into a Package:

package {
 public function compareInts(small:int, big:int):Boolean {
        if (small < big)
            return true;
            else
            return false;
 }
}

Answer 3

An AS3 constructor can never have a return value. If you want to keep this method in a class, then have the constructor just call an init() function and have init() return values.

Hope that helps clear up the "why?" that might be swirling in your head.