Sometimes it is desirable to document aspects of a package outside
the source-files. For this reason the system creates a link to files
using the extension .txt. The referenced file is processed
as Wiki source. The two fragments below illustrate the relation between
an
.pl file and a .txt file.
%! read_setup(+File, -Setup) is det.
%
% Read application setup information from File. The details
% on setup are described in setup.txt.
---+ Application setup data
If a file =|.myapprc|= exists in the user's home directory the
application will process this data using setup.pl. ...
