USE undocumented syntax

USE fileName$ example:

USE "PRG2:WHATEVER"

'does the same thing as:

LOAD "PRG2:WHATEVER",0
USE 2

It also works with EXEC (This is documented, but the documentation is misleading)

EXEC "PRG2:WHATEVER"

'does the same thing as:

LOAD "PRG2:WHATEVER",0
EXEC 2