I've posted this before many times before! The conversation has got
boring now - yawn!
I would challenge anybody to refactor this code without goto's.
https://github.com/eclipse/omr/blob/e9b85117d18c369108a9ddb790023103c35b4379/thread/common/omrthread.c#L246
On 2020-06-07 1:53 AM, Bob Bridges wrote:
Oh, you need an END-IF even for a single-statement IF? I forgot; I've been
thinking in REXX too long. In that case you're close; I guess I really meant
PERFORM 1050-LOOP THRU 1050-EXIT VARYING JC FROM 1 BY 1 TO 99
1050-LOOP.
IF X > 999 GOTO 1050-EXIT END-IF.
IF FIRST-NAME = "ROBERT" GOTO 1050-EXIT END-IF.
IF TYPE <> 195 GOTO 1050-EXIT END-IF.
IF NOT SO-ON GOTO 1050-EXIT END-IF.
IF NOT SO-FORTH GOTO 1050-EXIT END-IF.
[do such and such]
1050-EXIT.
I'm happy to hear someone else admit that a GOTO is conceivable under ~any~
circumstances. In my old shop I argued for GOTOs in three very strictly limited
circumstances, the other two being end-of-section and end-of-program. Some languages
allow for this by including some flavor of "leave" statement; all I want to do
with a GOTO is to simulate that part of structured programming. But at the particular
shop I have in mind, none of that could be contemplated, because all GOTOs are evil.
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* Law #21 of combat operations: The important things are always simple; the
simple things are always hard. */
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf
Of Joe Monk
Sent: Saturday, June 6, 2020 04:49
I think what you mean is this:
PERFORM 1050-LOOP THRU 1059-EXIT VARYING JC FROM 1 BY 1 UNTIL JC = 99
END-PERFORM
1050-LOOP.
IF FIRST-NAME NOT = "ROBERT"
GO TO 1059-EXIT
END-IF
IF TYPE NOT = 195
GO TO 1059-EXIT
END-IF
IF NOT SO-ON
GO TO 1059-EXIT
END-IF
IF NOT SO-FORTH
GO TO 1059-EXIT
END-IF
PERFORM 1050-SUCH-AND-SUCH END-PERFORM
1059-EXIT.
EXIT.
In structured programming, it is perfectly acceptable to use GO TO within a
paragraph. It is NOT acceptable to use GO TO outside of a paragraph.
--- On Sat, Jun 6, 2020 at 12:42 AM Bob Bridges <robhbrid...@gmail.com> wrote:
I realize this is a bit of a change in subject (and it's not as if we need
yet another one), but I avoid this construction. My phobia is based on an
extreme example: In their zeal never to use GOTOs, I've frequently seen
programmers write paragraphs like this:
PERFORM 1050-LOOP VARYING JC FROM 1 BY 1 TO 99
1050-LOOP.
IF X < 1000
IF FIRST-NAME NOT = "ROBERT"
IF TYPE = 195
IF SO-ON
IF SO-FORTH
EXECUTE 1050-SUCH-AND-SUCH
END-IF
END-IF
END-IF
END-IF
END-IF
Gives me a headache to try to evaluate that. Much better, in my opinion,
to introduce ONE LOUSY "GOTO EO-PARAGRAPH" like this:
PERFORM 1050-LOOP THRU 1059-LOOP VARYING JC FROM 1 BY 1 TO 99
1050-LOOP.
IF X > 999 GOTO 1059-LOOP.
IF FIRST-NAME = "ROBERT" GOTO 1059-LOOP.
IF TYPE <> 195 GOTO 1059-LOOP.
IF NOT SO-ON GOTO 1059-LOOP.
IF NOT SO-FORTH GOTO 1059-LOOP.
EXECUTE 1050-SUCH-AND-SUCH
1059-LOOP.
Keep in mind I haven't programmed in COBOL since Y2K; I had to look up the
syntax, I probably got part of it wrong nonetheless, and I'll bet there are
easier ways to do it nowadays. In REXX, for example, they have the ITERATE
statement:
do jc=1 to 99
if x>99 then iterate
if firstname='ROBERT' then iterate
if type<>195 then iterate
if \soon then iterate
if \soforth then iterate
call suchandsuch
end
However you do it, I vastly prefer skip-to-next-item over nested Ifs. But
I confess that one single nested IF is not going to give me a headache; I
just react when I see one. Not your fault :).
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On
Behalf Of Gibney, Dave
Sent: Friday, June 5, 2020 16:17
Using OP
IF TVOLL (IND1) NOT = HIGH-VALUE
AND SMOD (IND1) = 'B' OR 'R'
I would do
IF TVOLL (IND1) NOT = HIGH-VALUE
IF SMOD (IND1) = 'B' OR 'R'
Do the stuff
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