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RETURN |
Return From a Subroutine |
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RETURN expression[$] |
Where:
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expression[$] |
Value to be returned from a multi-line function, embedded I/O procedure, or OOP method logic. String or numeric expression. |
The RETURN directive is used to terminate a subroutine. This directive can also be used to pass a value back from a multi-line function, an embedded I/O procedure, or OOP method logic.
Terminate Subroutine
The RETURN directive is used as the terminator for a GOSUB or SETESC subroutine. Control is returned to the initiating statement. If the subroutine has been accessed externally via the PERFORM directive, the RETURN statement will both terminate the subroutine and return control to the initiating program.
If PxPlus encounters a RETURN directive without an associated subroutine, PxPlus returns an Error #27: Unexpected or incorrect WEND, RETURN or NEXT.
RETURN must be the final directive in a compound statement.
Use the *RETURN label to emulate this directive in a statement reference.
Terminate Procedure, Specify Value
RETURN expression[$]
The RETURN directive serves a similar purpose in a multi-line function, embedded I/O, or OOP function procedure as it does in a typical subroutine; however, this version of a RETURN statement also passes back a value, expression[$].
Multi-Line Function
When used in a multi-line definition of a user-defined function (DEF FN), the RETURN directive terminates the function procedure and passes back a result. The specified value must match the data type of the function definition itself.
Embedded I/O Procedure
The RETURN directive terminates an embedded I/O procedure and returns a value to the file handler, which it may use to determine the next operation.
OOP Method Logic
In Object Oriented Programming, the RETURN directive terminates the method logic and passes back a result.
GOSUB.. Execute Subroutine
SETESC Set Interrupt Processing
Labels/Logical Statement References
EXIT Terminate Subprogram and Return
DEF FN Define Function
Use in terminating/exiting a subroutine:
0100 ! 100
0110 input "Enter start date DD/MM/YY: ",D$
0120 gosub 1000
0130 let D1$=D$
0140 input "Enter ending date DD/MM/YY: ",D$
0150 gosub 1000
0160 let D2$=D$
0170 print "DONE"; stop
1000 ! 1000
1010 if len(D$)<>8 then goto 1080
1020 if D$(3,1)<>"/" or D$(6,1)<>"/" then goto 1080
1030 let D=num(D$(1,2),err=1080),M=num(D$(4,2),err=1080),Y=num(D$(7,2),err=1080)
1040 if D<1 or D>31 then goto 1080
1050 if M<1 or M>12 then goto 1080
1060 return
1070 !
1080 print "Invalid: Restart..."
1090 exitto 0100
->run
Enter start date DD/MM/YY: 033199
Invalid: Restart...
Enter start date DD/MM/YY: 31/03/99
Enter ending date DD/MM/YY: 16/04/99
DONE
Use in terminating function and returning value:
0010 def fn%SHRINK$(local X$)
0020 local I
0030 I=pos(" "=X$)
0040 if I <> 0 then X$=X$(1,I-1)+" "+X$(I+2); goto 0040
0050 return X$
0060 end def0010 def class "Customer"
0020 property CUST_NO$,NAME$,ADDR1$,ADDR2$,CITY$,AMT_OWING,LAST_ORD_DT$
0030 function Find(X$)Get_Customer
0040 function Update()Upd_Customer
0050 local File object
0050 end def
0100 ON_CREATE: enter Db
0110 File = Db'Open("ARCUST")
0120 return
0200 Get_Customer: enter C$
0210 read (File'Channel,key=C$) ! Loads all the variables
0220 return 1
0300 Upd_Customer:
0310 write (File'Channel)
0320 return 1