The difference between New and old code systems is:
Replaced '*' with 'x' for multiply.
Now when you need to use a variable value use vars*<var name> instead of <var name>.
now you'll need to use methods.getPlayer(), methods.getWorld(), methods.getFile() instead of getPlayer(), getWorld(), getFile().
If you want to use math in any argument you need to put ! before the arguments, example: player.setHealth(!5 x 2).
If you want to use methods in an arguments such as: 'player.getHealth' inside player.setHealth(). now you can't you need to make a variable with the value. example: 'var Number health = player.getHealth()', 'player.setHealth(!vars*health / 2)'.
In new code system, you can change the a variable value afterwards, example: 'var Number health = player.getHealth()', 'vars*health => 10'