3.3.1 Locating things to edit
The 
central predicate for editing something is edit/1, 
an extensible front-end that searches for objects (files, predicates, 
modules, as well as XPCE classes and methods) in the Prolog database. If 
multiple matches are found it provides a choice. Together with the 
built-in completion on atoms bound to the TAB key this 
provides a quick way to edit objects:
?- edit(country). Please select item to edit: 1 chat:country/10 '/staff/jan/lib/prolog/chat/countr.pl':16 2 chat:country/1 '/staff/jan/lib/prolog/chat/world0.pl':72 Your choice?