$FUNCNAME$
  GETPREVALIDATE()
$CATEGORY$
  TERMINAL/IO
$SUMMARY$
   Prevalidate a Get object
$SYNTAX$
     GETPREVALIDATE(<oGet>) --> lSuccess
$ARGUMENTS$
     <oGet> is a reference to the current Get object.
$RETURNS$
     GETPREVALIDATE() returns a logical value indicating whether the Get
     object has been prevalidated successfully.
$DESCRIPTION$
     GETPREVALIDATE() is a function that validates the Get object for
     editing, including evaluating Get:preBlock (the WHEN clause) if it is
     present.  The logical return value indicates whether the GET has been
     prevalidated successfully.

     Get:exitState is also set to reflect the outcome of the prevalidation:

     <PRE> Get:exitState Values
     ------------------------------------------------------------------------
     Getexit.ch   Meaning
     ------------------------------------------------------------------------
     GE_NOEXIT    Indicates prevalidation success, okay to edit
     GE_WHEN      Indicates prevalidation failure
     GE_ESCAPE    Indicates that a CLEAR GETS was issued
     ------------------------------------------------------------------------
     </PRE>

     Note that in the default system, a Get:exitState of GE_ESCAPE cancels
     the current GET and terminates READMODAL().
$EXAMPLES$
       This example demonstrates the GETPREVALIDATE() function.

	IF GETPREVALIDATE (oGet)
	   // process the get
	ELSE
	   // WHEN clause not satisfied
	   // give a warning to the user
	ENDIF
$SEEALSO$
  GETAPPLYKEY(),GETDOSETKEY(),GETPOSTVALIDATE()
$END$
