RE: Constant definitions (was: Visual RPG vs. Other Visual ....

Nelson,

I see what you're getting at, you use the constants when evaluating the
contents of the field, and having those constants defined right next to the
field.

My only beef with it is that i believe your goal would be better served
describing the constants outside of the DS and commenting the DS if
desired.

by making them part of the DS, someone who wanted to modify the program and
hadn't read this thread or that particular section of the
documentation/un-documentation, the following 'facts' might be assumed...

1. somehow, the constants ARE inforcing the integrity of the field, much
like a DDS values keyword?
2. the constants ARE part of the data structure, and actually take up space
in the DS buffer?

both of which are not true, because:

  ONLY due to the fact that it is a constant, rather than a variable, it is
described to the program OUTSIDE the data structure, having absolutely
nothing to do with the DS proper.

This, to me, is very confusing and could send someone on a wild goose chase
trying to track down why the ds doesn't look like he/she thought is should.

listing the valid values here doesn't enforce the integrity of the data,
any more than a comment would.

I agree with Barbara that the bug, if it is a bug, shouldn't be 'fixed', to
keep existing programs compilable, (maybe adding a 10 or 20 level warning
message might do the trick?) but imo, using an 'undocumented feature' in
this manner strikes me as a bit of obfuscation, rather than alumination...

have a great weekend all...

rick

----original message-------
Richard,
Here's a ds in which all the allowable values for the field Col_Fld_Type
are
listed right under it's definition, even though it is part of a larger data
structure. Doesn't change anything except the readability or
self-documentation of the ds.  With proper indenting (which doesn't come
across too well), it is very evident what the constants are used for:

D ds_Sfl_Layout   DS
D  Column_Array                       DIM(400)
D   Col_SQLDASeq                 5I 0 OVERLAY(Column_Array:1)
D   Col_Disp_Seq                 5I 0 OVERLAY(Column_Array:*NEXT)
D   Col_Incl_Flg                  N   OVERLAY(Column_Array:*NEXT)
D   Col_Null_Flg                  N   OVERLAY(Column_Array:*NEXT)
D   Col_Fld_Type                10A   OVERLAY(Column_Array:*NEXT)
D    cstBinary    C                   CONST('*BINARY')
D    cstChar      C                   CONST('*CHAR')
D    cstDate      C                   CONST('*DATE')
D    cstPacked    C                   CONST('*PACKED')
<snip>