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— Statements —

ESCAPE

Structured Mode Syntax

`ESCAPE`		`TOP` [`REPOSITION`]
		`BOTTOM` [(`r`)] [`IMMEDIATE`]
		`ROUTINE` [`IMMEDIATE`]
		`MODULE` [`IMMEDIATE`]

Reporting Mode Syntax

`ESCAPE`			`TOP` [`REPOSITION`]
			`BOTTOM` [(`r`)] [`IMMEDIATE`]
			`ROUTINE` [`IMMEDIATE`]
			`MODULE` [`IMMEDIATE`]

This document covers the following topics:

Function
Syntax Description
Example

For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.

Related Statements:

FOR | REPEAT | PROCESS PAGE MODAL
CALL | CALL FILE | CALL LOOP | CALLNAT | DEFINE SUBROUTINE | FETCH | PERFORM

Belongs to Function Group:

Function

The ESCAPE statement is used to interrupt the linear flow of execution of a processing loop or a routine.

With the keywords TOP, BOTTOM and ROUTINE you indicate where processing is to continue when the ESCAPE statement is encountered.

An ESCAPE TOP/BOTTOM statement, when encountered for processing, will internally refer to the innermost active processing loop. The ESCAPE statement need not be physically placed within the processing loop.

If an ESCAPE TOP/BOTTOM statement is placed in a routine (subroutine, subprogram, or program invoked with FETCH RETURN), the routine(s) entered during execution of the processing loop will be terminated automatically.

Additional Considerations

More than one ESCAPE statement may be contained within the same processing loop.

The execution of an ESCAPE statement may be based on a logical condition. If an ESCAPE statement is encountered during processing of an AT END OF DATA, AT BREAK or AT END OF PAGE block, the execution of the special condition block will be terminated and ESCAPE processing will continue as required.

If an ESCAPE statement is encountered during processing of an if-no-records-found condition, no loop-end processing will be performed (equivalent to ESCAPE IMMEDIATE).

Syntax Description

Syntax Element	Description
`ESCAPE TOP`	Top Option: `TOP` indicates that processing is to continue at the top of the processing loop. This starts the next repetition of the processing loop.
`REPOSITION`	Top Reposition Option: When an `ESCAPE TOP REPOSITION` statement is executed, Natural immediately continues processing at the top of the active `READ` loop, using the current value of the search variable as new start value. At the same time, `ESCAPE TOP REPOSITION` resets the system variable `*COUNTER` to zero. `ESCAPE TOP REPOSITION` can be specified within a `READ` statement loop accessing an Adabas database. The `READ` statement concerned must contain the option `WITH REPOSITION`.
`ESCAPE BOTTOM`	Bottom Option: `BOTTOM` indicates that processing is to continue with the first statement following the processing loop. The loop is terminated and loop-end processing (final `BREAK` and `END DATA`) is executed for all loops being terminated. In reporting mode, `ESCAPE BOTTOM` is the default.
`(r)`	Statement Reference: Notation `(r)`: If `BOTTOM` is followed by a label or reference number, processing will continue with the first statement following the processing loop identified by the label or reference number. A label or a reference number can only be specified if the `ESCAPE BOTTOM` statement is physically placed within the referenced processing loop.
`IMMEDIATE`	Immediate Option: If you specify the keyword `IMMEDIATE`, no loop-end processing will be performed.
`ESCAPE ROUTINE`	Routine Option: This option indicates that the current Natural routine, which may have been invoked via a `PERFORM`, `CALLNAT`, `FETCH RETURN`, or as a main program, is to relinquish control. In the case of a subroutine, processing will continue with the first statement after the statement used to invoke the subroutine. In the case of a main program, Natural command mode will be entered. All loops currently active within the routine will be terminated and loop-end processing performed as well as final processing for user-initiated (`PERFORM BREAK`) processing. If the program containing the `ESCAPE ROUTINE` is executed as a main program (Level 1), final end-page processing is performed.
`ESCAPE MODULE`	Module Option: This option indicates that the entire current program level, with all internal subroutines, is to relinquish control. The control is then returned to the object of the former program level. If `ESCAPE MODULE` is used in a hierarchy of internal subroutines, it allows to escape all routines working at this level at once. If no internal subroutine is active, `ESCAPE MODULE` has the same result as `ESCAPE ROUTINE`. `ESCAPE MODULE` is only relevant in inline subroutines. In external subroutines, subprograms and invoked programs, it has the same effect as `ESCAPE ROUTINE`. As with `ESCAPE ROUTINE`, loop-end processing will be performed. However, if you specify the keyword `IMMEDIATE`, no loop-end processing will be performed.

Example

** Example 'ESCEX1': ESCAPE                                             
************************************************************************
DEFINE DATA LOCAL                                                       
1 EMPLOY-VIEW VIEW OF EMPLOYEES                                         
  2 CITY                                                                
  2 FIRST-NAME                                                          
  2 NAME                                                                
  2 AREA-CODE                                                           
  2 PHONE                                                               
*                                                                       
1 #CITY (A20) INIT <' '>                                                
1 #CNTL (A1)  INIT <' '>                                                
END-DEFINE                                                              
*                                                                       
REPEAT                                                                  
  INPUT 'ENTER VALUE FOR CITY:  ' #CITY                                 
      / 'OR ''.'' TO TERMINATE  '                                       
  IF #CITY = '.'                                                        
    ESCAPE BOTTOM                                                       
  END-IF                                                        
  /*                                                            
  FND. FIND EMPLOY-VIEW WITH CITY = #CITY                       
    /*                                                          
    IF NO RECORDS FOUND                                         
      WRITE 'NO RECORDS FOUND'                                  
      ESCAPE BOTTOM (FND.)                                      
    END-NOREC                                                   
    AT START OF DATA                                            
      INPUT (AD=O) 'RECORDS FOUND:' *NUMBER //                  
                   'ENTER ''D'' TO DISPLAY RECORDS' #CNTL (AD=M)
      IF #CNTL NE 'D'                                           
        ESCAPE BOTTOM (FND.)                                    
      END-IF                                                    
    END-START                                                   
    /*                                                          
    DISPLAY NOTITLE NAME FIRST-NAME PHONE                       
  END-FIND                                                      
END-REPEAT

Output of Program ESCEX1:

ENTER VALUE FOR CITY:  PARIS
(OR '.' TO TERMINATE)

After entering and confirming city name:

RECORDS FOUND:        26
ENTER 'D' TO DISPLAY RECORDS D

Result after entering and confirming D:

        NAME              FIRST-NAME         TELEPHONE   
-------------------- -------------------- ---------------
                                                         
MAIZIERE             ELISABETH            46758304       
MARX                 JEAN-MARIE           40738871       
REIGNARD             JACQUELINE           48472153       
RENAUD               MICHEL               46055008       
REMOUE               GERMAINE             36929371       
LAVENDA              SALOMON              40155905       
BROUSSE              GUY                  37502323       
GIORDA               LOUIS                37497316       
SIECA                FRANCOIS             40487413       
CENSIER              BERNARD              38070268       
DUC                  JEAN-PAUL            38065261       
CAHN                 RAYMOND              43723961       
MAZUY                ROBERT               44286899       
FAURIE               HENRI                44341159       
VALLY                ALAIN                47326249       
BRETON               JEAN-MARIE           48467146       
GIGLEUX              JACQUES              40477399       
KORAB-BRZOZOWSKI     BOGDAN               45288048       
XOLIN                CHRISTIAN            46060015       
LEGRIS               ROGER                39341509       
VVVV

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