newbie question - Turbo Prolog

Hi everyone,

I'm using an old version of Turbo Prolog for a class at school, and we
have a few simple programs to implement as an assignment.
Since we have quite a few list processing programs to write, we're
using a domains.pro file for all the programs which looks like this:

domains

integerlist = integer*
reallist = real*
charlist = char*
symbollist = symbol*

Now, the problem I'm having is that when I try to write a program for
finding the union of two sets, for example, I include a file called
memberlist.pro which finds out if an object is a member of a list or
not, and deleteobj.pro, which deletes an object from a list, both of
which use domains.pro. And Prolog complains in the union program that
the domains have already been declared, since domains.pro is being
included twice.
Is there any way around this? The only solution I have found so far is
to make copies of my memberlist and deleteobj files without the
include "domains.pro" and use them in the union program, and I have a
lot of small files like this that I need to use in other programs.

Thanks for any help,
Sunayana.

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