Default param cannot be null?

Question

What kind of stupid rule of is that...unless Im doing it wrong.
In AS3 doing:
public function bla(string:String=null){}
doesnt seem to work as I get an error 1 argument given, 0 expected.
if I do public function bla (string:String, i:int = null){}
i am told it wants 1 not 2 arguments.....
How do I get around this? every other language allows me to et a param as default to null and still pass in two arguments....

Answer 1

oh well i didnt know they cant be null.....
I dont want to pass an unlknown amount of variables.
This example if what I am tryng to do...
public function testIdea(someNumber:int = 0, someString:String = ""):String //notice how the params for this function are already set
     var str:String = "";
     if(someString == undefined)
         someString = "Adam"; //what if someString is not set? we set it to Adam
    if(someNumber > 0 )
       //Apend the number we entered, IF we entered one to the someString variable. If we entered no name and a number
       // this if statement would execute.
       str = someString + " " + someNumber;
       return str;
  //if no name and no hnumber or just a name and no number was entered.
  return "Adam with Number less then or equal to 0";
In this example, when this function is called and the user inputs:
testIdea(10, "adam");
they should get back: adam 10
this method takes two arguments. a int and a string. How ever the string can be left blank thus you could, in theory, do: testIdea(10); and get back: Adam 10
How ever Actionscript spazzes out and sais, 1 argument given, 2 expected....In this case I should be allowed to pass 1 argument. Heck I could eve do: testIdea() and get: Adam with Number less then or equal to 0
I could even do: testIdea("Sam") and get: Sam with Number less then or equal to 0  - but I cant because Actionscript wants two argements passed. I am not looking to use rest because I am not looking to pass more then a maximum of two arguments. both of which are already set for me and have defualt functionality for, if I choose to pass no arguments or if I pass one argument or if I pass two arguments.
a real world example is:
PHP optional paremeters out lines EXACTLY what I mean
function makecoffee($type = "cappuccino")
    return "Making a cup of $type.\n";
echo makecoffee(); // $type = cappuccino
echo makecoffee(null); //$type = cappucino
echo makecoffee("espresso"); //$type = espresso
now Im not sure, maybe I have been doing it right all along and I am just missing some concept. in that case sorry for wasting your time. How ever it seems to me that Actionscript in this case would say:
0 aurguments given, 1 expected. I dont think action script has "Optional Paremeters" which is what im trying to do...Havent googled that yet cause I didnt know that was the word(s) to google untill I found this in PHP >_<