CONTINUE VS NEXT SENTENCE

[Michael F Gleason]

I think I recall reading that NEXT SENTENCE is or will be discontinued using CONTINUE in its place. I am old enough to use NEXT SENTENCE but have been using CONTINUE as of late. This is my question. In the code
IF WS-TALLY EQUAL ZERO
STRING WS-CUR-DIR DELIMITED BY " "
"\" DELIMITED BY " "
WS-FILE1 DELIMITED BY " "
INTO WS-NEW-FILE1
ON OVERFLOW DISPLAY "STRING OVERFLOWED"
DISPLAY " "
MOVE SPACE TO WS-NEW-FILE1
CONTINUE
END-STRING
MOVE WS-NEW-FILE1 TO WS-FILE1
DISPLAY "New INPUT " TRIM(WS-FILE1)
DISPLAY " "
END-IF.
Will an OVERFLOW condition skip to the END-IF? Or will it skip to the MOVE that follows the END-STRNG?

       Michael:-)

       Never mind.
       I forced an OVERFLOW and CONTINUE goes to the END-STRING.
       NEXT SENTENCE goes to the END-IF.

[Vincent (Bryan) Coen]

On 02/10/2023 22:54, Michael F Gleason wrote:

I think I recall reading that NEXT SENTENCE is or will be discontinued
using CONTINUE in its place. I am old enough to use NEXT SENTENCE but
have been using CONTINUE as of late. This is my question. In the code
IF WS-TALLY EQUAL ZERO
STRING WS-CUR-DIR DELIMITED BY " "
"\" DELIMITED BY " "
WS-FILE1 DELIMITED BY " "
INTO WS-NEW-FILE1
ON OVERFLOW DISPLAY "STRING OVERFLOWED"
DISPLAY " "
MOVE SPACE TO WS-NEW-FILE1
CONTINUE
END-STRING
MOVE WS-NEW-FILE1 TO WS-FILE1
DISPLAY "New INPUT " TRIM(WS-FILE1)
DISPLAY " "
END-IF.
Will an OVERFLOW condition skip to the END-IF? Or will it skip to the
MOVE that follows the END-STRNG?

Assuming I am reading it correctly you want within the on overflow check
disp 2 msgs the continue AFTER the END-STRING BUT, BUT

If CONTINUE is a direct replacement for NEXT SENTENCE then that is NOT
the flow  -  at least according to my reading.

Best bet it to do similar in a test program and trace out what it
actually does on a JIC basis having compiled the prog as -d -f
-ftraceall etc.

See the prog guide which states :

The CONTINUE statement is a no-operation statement that may be coded
anywhere an imperative
statement (see [Imperative Statement], page 678) may be coded.

1. The CONTINUE statement _has no effect _on the execution of the program.

2. This statement (perhaps in combination with an appropriate comment
or two) makes
     a convenient “place holder” — particularly in ELSE (see [IF], page
318) or WHEN (see
[EVALUATE], page 301) clauses where no code is currently expected
to be needed, but
     a place for code to handle the conditions in question is to be
reserved in case it’s ever
     needed.

3. The optional extension of (AFTER) when used with the CONTINUE
statement pauses execution for a specified length of time.

The underlines are mine.

Now for the IF and NEXT SENTENCE

again in the PG under 7.8.22

1. The clause NEXT SENTENCE may be substituted for either
   imperative-statement, but not
   both. If control reaches a NEXT SENTENCE clause due to the truth or
   falsehood of conditional-
   expression, control will be transferred to the first statement of the
   next sentence found in
   the program (the first statement after the next period).

NEXT SENTENCE was needed for COBOL programs that were coded according to
pre-1985
standards that wish to nest one IF statement inside another. See [Use of
VERB/END-
VERB Constructs], page 52, for an explanation of why NEXT SENTENCE was
necessary.

Programs coded for 1985 (and beyond) standards don’t need it, instead
using the explicit
scope-terminator END-IF to inform the compiler where
imperative-statement-2 (or
imperative-statement-1 if there is no ELSE clause coded) ends. New
GnuCOBOL pro-
grams should be coded to use the END-IF scope terminator for IF
statements. See [Use of
VERB/END-VERB Constructs], page 52, for additional information.

Now look at 2.2.7 Use of VERB/END-VERB Constructs regarding NEXT SENTENCE

Good luck and yes I recommend a test prog to check what exactly the
compiler does - as it does not mean the compiler has read the manual :)

[Simon Sobisch]

if course NEXT SENTENCE will not skip to either END-STRING or END-IF - it will skip directly to after the next separator period. And currently it is directly after the END-IF, but if it is ever changed (for example because there's code added afterwards or the STRING statement is moved out to a PERFORMed procedure´, then "all of a sudden" it will skip to somewhere else.... wherever the NEXT SENTENCE starts.

[Michael F Gleason]

Bryan.
Thanks for the quick reply.
I have done all your recommendations for reading before.
You were so quick in replying that you did not see that I edited my post with a never mind.
The answer to my question is to use the NEXT SENTENCE statement.

I only wander if NEXT SENTENCE will become obsolete, as the manual seems to rant against it.

Michael :-)

[Vincent (Bryan) Coen]

On 02/10/2023 23:54, Michael F Gleason wrote:

Bryan.
Thanks for the quick reply.
I have done all your recommendations for reading before.
You were so quick in replying that you did not see that I edited my
post with a never mind.
The answer to my question is to use the NEXT SENTENCE statement.

I only wander if NEXT SENTENCE will become obsolete, as the manual
seems to rant against it.

Michael :-)

Personally I would never 'assume' about anything with the Cobol language
now that the so called standard is done via a different agency as
against CODASYL  etc that appear to just want money for a digital copy
of their standards and a silly amount at that  - sorry bitten once and
that was more than enough.

The good news is that if it does get removed it is unlikely to be
removed from any compiler any time soon - say within a 10 year period.

By which time it might come back :)

Stranger things have happened with IT standards over the years.- there
again may be my memory is better than I thought :(

[Simon Sobisch]

NEXT SENTENCE was made archaic with COBOL 85 (and it is still in). Here is what COBOL 2023 says about those elements and specific on the statement from Annex F:

The purpose of the archaic language element designation is to discourage the use in new programs of some features that are unreliable, poor programming practice, or ill-defined -- where better programming techniques are available in standard COBOL. These elements are classified as archaic rather than obsolete because their use in existing programs might be too extensive to warrant removal in the next edition of standard COBOL.
There is no schedule for deleting archaic elements from standard COBOL; however, this may be reevaluated for any future editions of standard COBOL.
Archaic features are likely to cause future compiler errors. It is therefore recommended that they are avoided in new source units and replaced in existing ones. {...]

NEXT SENTENCE phrase in the IF and SEARCH statements.
This phrase can be confusing, especially when specified in a delimited scope statement. It is a common belief among users that control is transferred to a position after the scope delimiter rather than to a separator period that follows it somewhere. In addition, it is a common source of errors, especially for maintenance programmers who inadvertently insert a period somewhere before the actual terminating separator period. The CONTINUE statement and scope delimiters may be used to accomplish the same functionality and such constructs are clearer and less prone to error.

[Mickey White]

SInce I became a 'period less' programmer, I have never used Next Sentence or Continue.
Would the following work for you? ( I did not mess with the period)... My indents are are only for example..

IF  WS-TALLY EQUAL ZERO
    STRING WS-CUR-DIR DELIMITED BY " "
           "\" DELIMITED BY " "
           WS-FILE1 DELIMITED BY " "
           INTO WS-NEW-FILE1
        ON OVERFLOW DISPLAY "STRING OVERFLOWED"
                    DISPLAY " "
                    MOVE SPACE TO WS-NEW-FILE1
        NOT ON OVERFLOW 
                    MOVE WS-NEW-FILE1 TO WS-FILE1
                    DISPLAY "New INPUT " TRIM(WS-FILE1)
                    DISPLAY " "
    END-STRING
END-IF.

[Michael F Gleason]

Thanks Mickey.
I missed the NOT ON OVERFLOW when reading about STRING.
I have been trying to code a clean sentence but your example is good/correct way to do it.

Michael :-)