Re: RPG Free Syntax for Externally Described Data Structure

As Jon Paris noted, the rules for EXTNAME are different for fixed vs free format:

• In a free-form definition, the file-name and format-name parameters must be character literals or
named constants representing character literals. If a parameter is a named constant, the constant must
be defined prior to the definition statement.
• In a fixed-form definition, the file-name and format-name parameters can be either names or character
literals.

In Mohan's original question it's unclear whether the parameter for EXTNAME is the actual name of the file, or the name of a character field.  Note that in free-form, the parameter for EXTNAME cannot be the name of a character field; if it's not a character literal, it must be the name of a named constant representing a character literal.

As Brian noted, this would work:

DCL-DS DS_WMS0104 EXTNAME('LMBJDS104W') PREFIX('W_') END-DS;

or

DCL-C LMBJDS104W CONST('LMBJDS104W');
DCL-DS DS_WMS0104 EXTNAME(LMBJDS104W) PREFIX('W_') END-DS;

But this wouldn't work because the named constant must be defined before it's used:

DCL-DS DS_WMS0104 EXTNAME(LMBJDS104W) PREFIX('W_') END-DS;
DCL-C LMBJDS104W CONST('LMBJDS104W');

And this wouldn't work because the parameter for EXTNAME, if it's not a character literal, must be the name of a named constant, not a field.

DCL-S LMBJDS104W  CHAR(10) INZ('LMBJDS104W');
DCL-DS DS_WMS0104 EXTNAME(LMBJDS104W) PREFIX('W_') END-DS;

--
*Peter Dow* /
Dow Software Services, Inc.
909 793-9050
petercdow@xxxxxxxxx
pdow@xxxxxxxxxxxxxx /

On 4/26/2024 12:51 PM, Brian Parkins wrote:

Nearly. Needs quotes around the EXTNAME item, i.e. ExtName('LMBJDS104W')

From the RPG IV Reference:

"• In a free-form definition, the file-name and format-name parameters must be character literals or named constants representing character literals. If a parameter is a named constant, the constant must be defined prior to the definition statement."

On 26/04/2024 19:30, Peter Dow wrote:

Something like

DCL-DS DS_WMS0104 EXTNAME(LMBJDS104W) PREFIX('W_') END-DS;

or

DCL-DS DS_WMS0104
     EXTNAME(LMBJDS104W)
     PREFIX('W_')
END-DS;

--
*Peter Dow* /
Dow Software Services, Inc.
909 793-9050
petercdow@xxxxxxxxx
pdow@xxxxxxxxxxxxxx /

On 4/26/2024 11:13 AM, Mohan Eashver wrote:

Happy Friday to you, how are you?

Will you please recommend a Free RPG syntax for the below ?



*     D DS_WMS0104    E DS EXTNAME(LMBJDS104W)     D
                               prefix('W_')*

----
Regards,
Mohan Eashver