I'm glad someone else is saying this about GOTOs. I was a COBOL developer for
years before getting into ACF2, and argued strenuously (and futilely) for
limited use of GOTOs at a shop where they'd all fallen for the religious belief
that GOTO is Satan. Three clear places where a GOTO can make a program better,
not worse, in COBOL:
1) GOTO EXIT-PROGRAM, where last messages be issued and other shutdown
processed.
2) GOTO END-OF-SECTION, sort of like a LEAVE statement in REXX.
3) GOTO TOP-OF-LOOP, which would correspond to the ITERATE in REXX. (Nowadays
I would probably write that as GOTO BOTTOM-OF-LOOP, but that's a detail.)
Now that I'm doing a lot of VBA programming, I often use that third example to
goto a label placed immediately before the Next statement; the label is
invariably IterateSomething (IterateRow, IterateRegion or whatever) to keep me
from forgetting that gotos are not to be used carelessly. So far I haven't
convinced myself that one of my VBA programs needs a GoTo of the second type,
but usually the reason I want it is to avoid one of those long series of
indented If statements you spoke of, and in VBA I can handle that with a
one-time Do block:
Do 'one time
If RegionCode Like "W*" Then Exit Do
If AddLimit < 99 Then Exit Do
Set oaddr = User.GetAddress
If Not CheckState(oaddr) Is Nothing Then Exit Do
' Now do what you wanted.
Loop While False
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* October: The Boston Red Sox, ending an 86-year drought, defeat the St. Louis
Cardinals to win the World Series. The Red Sox got into the Series thanks to
the fact that the New York Yankees -- who were leading the American-League
championships three games to none, and had all-stars at every position, not to
mention a payroll larger than the gross national product of Sweden -- chose
that particular time to execute the most spectacular choke in all of sports
history, an unbelievable Gag-o-Rama, a noxious nosedive, a pathetic gut-check
failure of such epic dimensions that every thinking human outside of the New
York Metropolitan area experienced a near-orgasmic level of happiness. But
there is no need to rub it in. -Dave Barry, 2004 in Review */
-----Original Message-----
From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of
David Crayford
Sent: Sunday, September 25, 2022 07:52
Another thing that makes me incredibly dubious about some of the opinions in
these videos is the hackneyed nonsense about "goto considered harmful". The
original paper was misunderstood in that all goto statements are harmful and
brainwashed a generation. Some of these videos present a trivial example using
goto and refactor it using if/ifelse. In programming languages without scope
based cleanup goto is not harmful. In fact it's leads to clean code as the
branch direction is always descending to a cleanup block. Happily for me, the
young guys I work with writing systems level Metal/C code haven't been seduced
by this dogmatic BS. Good C code uses goto statements as opposed to heavily
nested or superfluously functionally decomposed routines. The IBM Openj9 JVM C
code is a case in point
https://github.com/eclipse-openj9/openj9/blob/master/runtime/vm/classsupport.c.
I challenge anybody to write better code without goto statements.
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