Escape top and bottom

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1

Hi,

Could anyone please explain me escape top and bottom with clear example.
I know its in documentation but still explanation with example would be very helpful for me. Thankyou.

2 
DEFINE DATA LOCAL
1 COUNTER (I4)
1 BUTTON (A1)
END-DEFINE
*
FOR COUNTER = 1 TO 10
  IF COUNTER = 5
    PRINT 'Continue loop at the top...'
    ESCAPE TOP
  END-IF
  PRINT 'your counter is now:' COUNTER
  IF COUNTER = 8
    BUTTON := "N"
    INPUT 'Do you want to stop? (Y/N)' BUTTON (AD=MT)
    IF BUTTON = "Y"
      PRINT 'Ok - I stop it.'
      ESCAPE BOTTOM
    END-IF
  END-IF
END-FOR
*
PRINT 'It"s all over. Counter is now:' COUNTER
END
  1. Does this help?
3

Thankyou for this good example.

4

Thankyou for this good example.

5

ESCAPE BOTTOM IMMEDIATE is like a GO TO the statement after the end of a loop. By contrast, ESCAPE BOTTOM, all by itself (no IMMEDIATE) is not quite the same (except for REPEAT and FOR loops). With READ and FIND loops, ESCAPE BOTTOM first “finishes up” a loop before leaving the loop.

“Finishing up” a loop includes doing AT END OF DATA clauses, AT BREAK clauses, etc.

ESCAPE TOP is something of a misnomer; it does not “escape” a loop at all; it merely ends an iteration of the loop. I have met many programmers who thought it transferred control to the statement before a loop; not true. Functionally, ESCAPE TOP is basically identical to ACCEPT/REJECT statements.

steve

6

… sorry wrong posting …