Re: Data Structures with Structures

[Jim Langston <jimlangston@xxxxxxxxxxxxxxxx>]

The error you are getting should be saying you can't define the same
variable in 2 separate data structures.  Each time a DS is hit, it
starts a new data structure.

I don't believe that RPG, as of yet, allows nested data structures. 
I think you have to do something like this (untested code):

d @@faxcmds       ds
d  acmds                  1      2
d  bcmds                  1      2b 0
d  faxcmdds                     18a   dim(40)

d                 ds                 Based(faccmdptr)
d @faxcmdds               1     18
d  faxqual                1     10a
d  faxqualbc             11     14s 0
d  faxqualec             15     18s 0

d faccmdptr       S               *

...

C                   For       i = 1 to 10
C                   Eval      faccmdptr = %Addr(faxcmmds(i))
...

We are, in effect, doing the same thing, having a Data Structure inside
a Data Structure, but it works at run time.  We have to assign the address
of the data structure to the variable.

This might be changed in V5R1, not sure.

But think about this if your code were to work.  Your faxcmdds is an array.
How would you specify the variable faxqual in the 5th element?  "They" were
talking about doing something like faxcmdds(5)->faxqual or faxcmdds(5).faxqual,
but I don't think that's possible yet, even under V5R1.

Regards,

Jim Langston

Me transmitte sursum, Caledoni!

> Erick Garske wrote:
> 
> Am trying to define a data structure within a data structure. The first 
>structure @@faxcmds is input from a command list defining the number of 
>elements with the list, and the command structure itself. Up to 40 command can 
>be entered in the list.
> 
> The next structure defines the subfields within the command: One 10 character 
>field and two 4 digit fields.
> 
> I get an syntax error on this definition and am wondering just how this 
>should be formatted.
> 
> Thanks in advance for your help.
> 
> Regards,
> Erick
> 
> d @@faxcmds       ds                               
> d  acmds                  1      2                 
> d  bcmds                  1      2b 0              
> d  faxcmdds                     18a   dim(40)      
>                                                    
> d faxcmdds          ds                               
> d  faxqual                1     10a                
> d  faxqualbc             11     14s 0              
> d  faxqualec             15     18s 0
+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---