Alphanumeric to Numeric MOVE (was: [open-cobol-list] Two errors of Open-Cobol 09.7-11

[William M. Klein]

See comments below:

> -----Original Message-----

> This program give wrong results.
> ================
>       
> *****************************************************************
>        IDENTIFICATION DIVISION.
>        PROGRAM-ID. ERR02.
>       
> *****************************************************************
>        ENVIRONMENT DIVISION.
>        CONFIGURATION SECTION.
>        SPECIAL-NAMES.
>            DECIMAL-POINT IS COMMA.
>        INPUT-OUTPUT SECTION.
>       
> *****************************************************************
>        DATA DIVISION.
>        WORKING-STORAGE SECTION.
>        77  PGM           PIC X(8) VALUE 'ERR02   '.
>        77  PIC-X         PIC X(8).
>        77  PIC-9         PIC 9(5).
>        PROCEDURE DIVISION.
>        MAIN.
>            DISPLAY PGM.
>            MOVE '  2A' TO PIC-X.
> a)         MOVE PIC-X  TO PIC-9.
>            DISPLAY 'PIC-X >' PIC-X '<'.
> b)         DISPLAY 'PIC-9 >' PIC-9 '<'.
> c)         IF PIC-9 IS NUMERIC
>               DISPLAY 'PIC-9 IS     NUMERIC'
>            ELSE
>               DISPLAY 'PIC-9 IS NOT NUMERIC'
>            END-IF.
> d)         ADD 1 TO PIC-9.
>            DISPLAY 'PIC-9 >' PIC-9 '<'.
>            STOP RUN.
> ----------------------------
> This is the output of pgm:
> ERR02
> PIC-X >  2A    <
> PIC-9 >00002<
> PIC-9 IS     NUMERIC
> PIC-9 >00003<
> 
> The correct output must be:
> ERR02
> PIC-X >  2A    <
> PIC-9 >  2A <
> PIC-9 IS NOT NUMERIC
> Run-time error in line 28: wrong decimal data
> 
> Move a) must be permitted to permit c) test.

This is SORT-of true.  The ANSI Standard requires that you must be able
to move an alphanumeric elementary item to a numeric-integer data item.
HOWEVER, there are rules that allow for  "optimization" to detect
invalid data, so the compiler COULD issue a message. If the compiler
DOES allow this to compile, then the results of the MOVE are 

   UNDEFINED

See: CIB-24, A-44 and CIB-26, A-286.

The results of a move from an ALPHANUMERIC to a numeric-integer
elementary is ONLY defined if the alphanumeric sending item includes an
unsigned integer value.


 Display b) must show the field.

Not True - as the value in the field  PIC-9 is UNDEFINED (becuase the
MOVE was undefined)

> Every aritmetic operation must break the program with  an error.

  NOT true.  When a field contains "incompatible data" - then the use of
such a field is UNDEFINED - it may (or may not) cause an error - or "odd
results" - or anything else the compiler & run-time "want" (including
different results on odd-days of the months!!)

> A 
> move of PIC-9 in a field pic-edited (ZZ.ZZZ, for example) must give 
> error, too.

Only if the compiler & run-time "want" it to.

> ================
> Thank you, and sorry for my english!
> 
> Enrico Ceppi
>