Flow-control structures: Difference between revisions
Content added Content deleted
(→exit: corrected text concerning the EXIT statement, added other verbage. -- ~~~~) |
m (→return: added text to explain that the program may be a REXX subroutine or function. -- ~~~~) |
||
| Line 1,632: | Line 1,632: | ||
===return=== |
===return=== |
||
The RETURN statement terminates the running (REXX) program and passes control to the invoking program (it could be the shell/host/supervisor program). |
The RETURN statement terminates the running (REXX) program (which could be a subroutine or function) and passes control to the invoking program (it could be the shell/host/supervisor program). |
||
If the invoking program isn't a REXX program, the RETURN statement acts like an EXIT statement. |
|||
If the invoker is a REXX program and the RETURN statement has no EXPRESSION coded, and the invoker expects a RESULT, a SYNTAX condition (error) is raised --- which usually results in an abnormal termination of the invoking REXX program (this condition can be trapped, however). |
If the invoker is a REXX program and the RETURN statement has no EXPRESSION coded, and the invoker expects a RESULT, a SYNTAX condition (error) is raised --- which usually results in an abnormal termination of the invoking REXX program (this condition can be trapped, however). |
||
| Line 1,638: | Line 1,640: | ||
return expression</lang> |
return expression</lang> |
||
===signal=== |
===signal=== |
||
The SIGNAL statement can be thought of as a GO TO statement, however, on issuance of a SIGNAL statement, all executing DO loops and SELECTs are terminated. Essentially, that means that there is no real way to re-enter a DO loop once a SIGNAL statement is used. |
The SIGNAL statement can be thought of as a GO TO statement, however, on issuance of a SIGNAL statement, all executing DO loops and SELECTs are terminated. Essentially, that means that there is no real way to re-enter a DO loop once a SIGNAL statement is used. |
||