Re: Problem with non QUALIFIED DS

[Vern Hamberg <vhamberg@xxxxxxxxxxx>]

David

A dummy pointer is often used - before v6r1 - to declare a template 
variable or structure. It uses no memory, but it can be used to define 
other data structures with LIKEDS - a very handy thing. The basing 
pointer is also useful for data type definitions similar to what C/C++ 
has. You then use the LIKE keyword in your code.

Vern

David FOXWELL wrote:
> Thanks Birgitta, I shall keep your example for future reference. I find it a little hard reading pulling in 1 prototype at a time. Then again, the prototypes that caused my problem were prototypes I didn't even need!
>
> I have another question concerning the dummy pointer. It seems I am the only one here that never declares that pointer. It seems to me that if you declare it, you intend to use it, and all the data structures based on it can then be used. Is it unwise to declare the pointer for template based fields?
>
>   
> > -----Message d'origine-----
> > [mailto:rpg400-l-bounces@xxxxxxxxxxxx] De la part de Birgitta Hauser
> >
> > Hi,
> >
> > I'm also using a data structure of the field reference file
> > and data structures that are passed as parameters in my prototypes.
> > There is almost no field within my application that is not
> > defined with like or likeDS. Exceptions maybe indexes for
> > looping through arrays.
> > The data structures itself are (most times) in separate copy
> > members and surrounded with compiler directives. These copy
> > members are included within my prototypes (nested copy members).
> > Also the names of the references start with REF (except my
> > field reference file which is simply named FldRef).
> > In this way I never have any problems except I have to use
> > qualified data structures.
> >
> > All prototypes are located in a source file named QPROLESRC
> > with the same name as the source of the module or program All
> > Copy members for data structures and Reference fields are
> > located in a source file named QCPYLESRC.
> >
> > For example
> > Copy members for references
> >  /If Not Defined (FldRef)
> >  /Define (FldRef)
> > D FldRef       E DS                 ExtName(DWFldRef) Based(DummyPtr)
> >  /EndIf
> >
> >  /If Not Defined (RefDSMyFile)
> >  /Define (RefDSMyFile)
> > D RefDSMyFile  E DS                 ExtName(MyFile) Based(DummyPtr)
> >  /Endif
> >
> > Prototype 1
> >  /Include QCPYLESRC,FldRef
> >  /Include QCPYLESRC,MyFile
> >
> >  /If Not Defined (MyProc)
> >  /Define MyProc
> > D  MyProc         PR
> > D    Parm1                          Like(FldRef.MyField1)  const
> > D    Parm2                          LikeDS(RefDSMyFile)    Const
> >  /Endif
> >
> >  /If Not Defined MyFct
> >  /Define MyFct
> > D  MyFkt          PR                Like(FldRef.MyFieldY)
> > D     Parm1                         Like(FldRef.MyFieldx) Const
> >  /EndIf
> >
> > Prototype 2
> >  /Include QCPYLESRC,FldRef
> >  /Include QCPYLESRC,MyFile2
> >
> >  /If Not Defined (MyProc2)
> >  /Define MyProc2
> > D  MyProc2        PR
> > D    Parm1                          Like(FldRef.MyFieldA)  const
> > D    Parm2                          LikeDS(RefDSMyFile2)   Const
> >  /Endif
> >
> > Program/Module
> >
> > D/Include QPROLESRC,Proto1
> > D/Include QPROLESRC,Proto2
> >
> > Mit freundlichen Grüßen / Best regards
> >
> > Birgitta Hauser
> >