function_params.js

console.log("Begin example - 5");
// Adding of three numbers using a function

// Define an add function
function add(a,b,c){
	return a + b + c;
}

// EXTRA ARGUMENT IS IGNORED
var e = add(1,2,3,4);
console.log("Result =" + e); // The extra argument in the call is ignored

// ARGUMENTS NOT SUPPLIED BECOMES UNDEFINED
var f = add(1,1);
console.log("Result =" + f); 

// Notes for the add(1,1)
// The last parameter becomes undefined as it is not sent.
// becomes var f = add(1,1,undefined);
// at the function, 
//	the  return a + b + c 
//	becomes
// 	return 1 + 1 + undefined 
//		which results as NaN ( any number + undefined = NaN)