RE: Explanation of a datastructure as a parameter...

Hi Robert,

You can pass a data structure as Const so none of the subfields can change, or as not Const so all of the subfields can change. However if some should be changeable and some not, I suggest breaking them out into separate parameters.

If GetDaysOfWeek is setting the 7 days based on what field 1 is, then I suggest changing the call:

p GetDaysOfWeek b
d GetDaysOfWeek pi
d i_StartDay Const likeds(t_DayDs.Subfield1)
d o_DayDs likeds(t_DayDs)

Then you would call it as:
GetDaysOfWeek('Sunday': DayDs);


Hm, the procedure could still change subfield1 though... don't have the time to ponder this unfortunately.

-Kurt

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Robert Rogerson
Hi All,

I'm just hoping that someone can spare a moment and help me understand
this better.

I'm unclear how or if I can stipulate a parameter as const when passing a
datastructure defined like a template. For example, see the following
code.

h option(*nodebugio:*srcstmt)
d testpgm7 pr

d t_DayDs ds template
d subfield1 10a varying
d Overlay(t_DayDs)
d subfield2 like(subfield1)
d Overlay(t_DayDs: *next)
d subfield3 like(subfield1)
d Overlay(t_DayDs: *next)
d subfield4 like(subfield1)
d Overlay(t_DayDs: *next)
d subfield5 like(subfield1)
d Overlay(t_DayDs: *next)
d subfield6 like(subfield1)
d Overlay(t_DayDs: *next)
d subfield7 like(subfield1)
d Overlay(t_DayDs: *next)

d testpgm7 pi

d DayDs ds likeds(t_DayDs)

/free
*inlr = *on ;

DayDs.subfield1 = 'Sunday';
GetDaysOfWeek(DayDs);

Return;
/end-free

p GetDaysOfWeek b
d GetDaysOfWeek pi
d i_DayDs likeds(t_DayDs)
/free
*inlr = *on ;

If i_DayDs.subfield1 = 'Sunday';
i_DayDs.subfield2 = 'Monday';
Endif;

Return;
/end-free
p GetDaysOfWeek e

The datastructure DayDs is defined like the template t_DayDs. I don't
want the procedure GetDaysOfWeek to be able to change subfield1. If I had
passed all 7 parameters I would have specified the keyword const for the
first parameter.

How or can I do with a keyword when I pass a datastructure.

Thanks to all in advance.

Robert Rogerson