Putting extra classes into JS script a no no?

As I understand it, each JS script becomes a class with the same name as the script.

Occasionally, I've been adding a different class, which the script (or other scripts) may access, into a JS script in the same place as declaring the script variables:

Script "MyScript.js":

var foo : int; var bar : int;

class AnotherClass { var foo2 : int; var bar2 : int; function AnotherClass( f : int, b : int ) { foo2 = f; bar2 = b; } function Switch() { var tmp : int = foo2; foo2 = bar2; bar2 = tmp; } }

var another : AnotherClass;

function Start() { foo = 0; bar = 100; another = new AnotherClass( 3, 7 ); }

function Update() { foo++; if (foo==bar) { foo = 0; another.Switch(); } }

This works perfectly well, and I can make instances of AnotherClass from any script. But is this bad coding practice? Should I put AnotherClass into its own script? And is it different if I start coding in C# down the line?