CDO>  DEFINE PARTITION FIRST_BASELEVEL.
  CDO>  DEFINE CONTEXT DEVELOPMENT_CONTEXT.
  cont>   BASE_PARTITION FIRST_BASELEVEL.
  CDO>  SET CONTEXT DEVELOPMENT_CONTEXT
  CDO>  DEFINE COLLECTION COMPILER_C.             1
  CDO>  RESERVE COLLECTION COMPILER_C
  CDO>  DEFINE COLLECTION FRONT_END.
  CDO>  DEFINE COLLECTION BACK_END.
  CDO>  REPLACE COLLECTION COMPILER_C.
  CDO>  SET CONTEXT                               2
  CDO>  DEFINE RECORD ISSUES.

      In this example, the SET CONTEXT command sets the current
      context and implicitly defines a collection as the top
      collection. Subsequent definitions will be implicitly
      controlled.

      1  The DEFINE COLLECTION command sets the top collection for
         the current context. All definitions made within the current
         context are attached to the top collection. FRONT_END and
         BACK_END are attached to COMPILER_C.

      2  The SET CONTEXT command sets the current context to a null
         value. ISSUES is uncontrolled and unattached because it is
         defined outside a context.