Resolution:
Correct the code; then recompile.
Example:
The following example shows the correct use of AS and the incorrect use of AS IS.
       class-id A.
       method-id main static.
           declare o1 as object = type System.DateTime::Now
           declare dt1 = o1 as type System.DateTime       *> ok, will unbox o1
           declare dt2 = o1 as if type System.DateTime    *> Error, as there is no null value
           display dt1
       end method.
       end class.