RETURN: Difference between revisions

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(Created page with "'''RETURN''' is used in GOSUB procedures to return to the original call code line or a specified line label. {{PageSyntax}} :: '''RETURN''' [{''linelabel''|''linenumber''}] {{Parameters}} * RETURN without parameters returns to the code immediately following the original GOSUB call. * ''line number'' or ''linelabel'' after the RETURN statement returns code execution to that label. ''Usage:'' * Normally required at the end of a GOSUB procedure unless the...")
 
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* RETURN is not used in error handling procedures. Error procedures use [[RESUME]] ''line number'' or [[RESUME|RESUME NEXT]].
* RETURN is not used in error handling procedures. Error procedures use [[RESUME]] ''line number'' or [[RESUME|RESUME NEXT]].
* GOSUB procedures use line numbers or line labels designated with a colon after the number or label.
* GOSUB procedures use line numbers or line labels designated with a colon after the number or label.
* If RETURN is encountered without a previous [[GOSUB]] call a [[ERROR Codes|"RETURN without GOSUB" error]] is produced.  
* If RETURN is encountered without a previous [[GOSUB]] call a [[ERROR Codes|"RETURN without GOSUB" error]] is produced.
* To avoid errors, place [[GOSUB]] procedures AFTER the main program code [[END]] or after an [[EXIT SUB]] or [[EXIT FUNCTION]] call.
* To avoid errors, place [[GOSUB]] procedures AFTER the main program code [[END]] or after an [[EXIT SUB]] or [[EXIT FUNCTION]] call.


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five:
five:
{{Cl|PRINT}} "Aha! Five!"
{{Cl|PRINT}} "Aha! Five!"
{{Cl|RETURN}} '' ''
{{Cl|RETURN}}
{{CodeEnd}}
{{CodeEnd}}
{{OutputStart}}
{{OutputStart}}
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''Example 2:'' Returns to a specific line label.
''Example 2:'' Returns to a specific line label.
{{CodeStart}}
{{CodeStart}}
{{Cl|GOSUB}} hey  
{{Cl|GOSUB}} hey
{{Cl|PRINT}} "it didn't go here."  
{{Cl|PRINT}} "it didn't go here."
hoho:  
hoho:
{{Cl|PRINT}} "it went here."  
{{Cl|PRINT}} "it went here."
{{Cl|END}}  
{{Cl|END}}


hey:  
hey:
{{Cl|RETURN}} hoho  
{{Cl|RETURN}} hoho
{{CodeEnd}}
{{CodeEnd}}
{{small|Code by Cyperium}}
{{small|Code by Cyperium}}
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''See also:''  
''See also:''
* [[GOSUB]], [[GOTO]]
* [[GOSUB]], [[GOTO]]
* [[RESUME]]
* [[RESUME]]

Revision as of 02:29, 23 January 2023

RETURN is used in GOSUB procedures to return to the original call code line or a specified line label.


Syntax

RETURN [{linelabel|linenumber}]


Template:Parameters

  • RETURN without parameters returns to the code immediately following the original GOSUB call.
  • line number or linelabel after the RETURN statement returns code execution to that label.


Usage:

  • Normally required at the end of a GOSUB procedure unless the procedure returns using a loop.
  • RETURN is not used in error handling procedures. Error procedures use RESUME line number or RESUME NEXT.
  • GOSUB procedures use line numbers or line labels designated with a colon after the number or label.
  • If RETURN is encountered without a previous GOSUB call a "RETURN without GOSUB" error is produced.
  • To avoid errors, place GOSUB procedures AFTER the main program code END or after an EXIT SUB or EXIT FUNCTION call.


Example 1: Returns after a Gosub.

FOR a = 1 TO 10
PRINT a
IF a = 5 THEN GOSUB five
NEXT
END       'END or SYSTEM stop the program before the execution of a sub procedure

five:
PRINT "Aha! Five!"
RETURN
 1
 2
 3
 4
 5
Aha! Five!
 6
 7
 8
 9
 10


Example 2: Returns to a specific line label.

GOSUB hey
PRINT "it didn't go here."
hoho:
PRINT "it went here."
END

hey:
RETURN hoho
Code by Cyperium
it went here.



See also:



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