Pushing GameObject into JS Array returns NullReferenceException

Hey there!

I'm trying to obtain a gameObject inside one array of a class, into a JS Array, so that later I can put it inside a builtin GameObject[] array. However when I try to do that, the Editor returns a NullReferenceException. I can assure you that the variable that's trying to be accessed isn't empty.

Here's the class + array in the script shipWeapons.js:

 class WeaponSlot {
     var isEnabled : boolean = false; //checks if the weapon is enabled
     var weapon_go : GameObject; //weapon GameObject. It contains the projectile
     var phaser_point : GameObject; //if the weapon is a beam weapon, it fires from this game object
     var torpedo_point : GameObject; //if the weapon is a torpedo weapon, it fires from this game object
     var pulse_point : GameObject; //if the weapon is a pulse weapon, it fires from this game object
     var nextShot : float = 0.0f; //contains the time reference for when the weapon is able to fire again
     var isAngle : boolean = false; //checks if the target is inside the firing arch
     var isRange : boolean = false; //checks if the target is in range
     var isFiring : boolean = false; //checks if the weapon is firing
     var lastReload : float; //total time it took for the last reload
     
 }
 
 var weapon : WeaponSlot[];

And here's the attempt to build such array:

 //and now the inventory part
     //first get the weapon game objects of each weaponslot
     var Arr : Array;
     
     for(var x : int = 0; x < shipWea.weapon.Length; x++) 
     {
         Arr.Push(shipWea.weapon[x].weapon_go);
     }
     
     var newWeapons : GameObject[] = Arr.ToBuiltin(GameObject) as GameObject[];
     //now place it
     playerShip.shipInv.weapons = newWeapons;

So, does anyone have an idea why this isn't working, and returning a NullReferenceException on Arr.Push()?

Thanks in advance. João Borrego