J3/98-149

Date:     1998/05/08
To:       J3
From:     Henry Zongaro
Subject:  Interpretation request on WHERE statement in WHERE construct


NUMBER:
TITLE: Execution of a WHERE statement within a WHERE construct
KEYWORDS: WHERE statement, WHERE construct
DEFECT TYPE:
STATUS: J3 consideration in progress
QUESTION:  7.5.3.2 [113:17-19] indicates that:

   Upon execution of a WHERE statement or a WHERE construct statement that
   is part of a <where-body-construct>, the pending control mask is
   established to have the value m  .AND. (.NOT. mask-expr).
                                  c

[112:41-45] indicates that:

   Upon execution of an ENDWHERE statement, the control mask and pending
   control mask are established to have the values they had prior to the
   execution of the corresponding WHERE construct statement.  Following
   the execution of a WHERE statement that appears as a
   <where-body-construct>, the control mask is established to have the
   value it had prior to the execution of the WHERE statement.

Notice that after execution of an ENDWHERE statement, the pending control
mask is established to have the value it had prior to the execution of the
corresponding WHERE construct statement, but the same is not the case for
the pending control mask established by the execution of a WHERE statement
that appears as a <where-body-construct>.

According to this, the output of the following program

      PROGRAM P
        INTEGER :: A(2) = 0, B(2) = 0

        WHERE((/.TRUE.,.TRUE./))
          WHERE((/.TRUE.,.FALSE./)) A = 1
        ELSEWHERE
          A = 2
        END WHERE
        PRINT *, A

        WHERE((/.TRUE.,.TRUE./))
          WHERE((/.TRUE.,.FALSE./))
            B = 1
          END WHERE
        ELSEWHERE
          B = 2
        END WHERE
        PRINT *, B
      END PROGRAM P

will be

 1 2
 1 0

Was this difference in behaviour intended by the committee?

ANSWER:
EDIT:
SUBMITTED BY: Henry Zongaro
HISTORY: 98-149   m145 Submitted