The SWI-Prolog development environment consists of a number of 
interrelated but not (yet) integrated tools. Here is a list of the most 
important features and tips.
- Atom completion
 The console41On Windows this is 
realised by swipl-win.exe, on Unix through the GNU readline library, 
which is included automatically when found by configure. 
completes a partial atom on theTABkey and shows 
alternatives on the commandAlt-?.
 
- Use edit/1 
for finding locations
 The command edit/1 
takes the name of a file, module, predicate or other entity registered 
through extensions and starts the user's preferred editor at the right 
location.
 
- Select editor
 External editors are selected using theEDITORenvironment 
variable, by setting the Prolog flag editor, 
or by defining the hook qpredrefprolog_editedit_source1.
 
- Update Prolog after editing
 Using make/0, 
all files you have edited are re-loaded.
 
- PceEmacs
 Offers syntax highlighting and checking based on real-time parsing of 
the editor's buffer, layout support and navigation support.
 
- Using the graphical debugger
 The predicates guitracer/0 
and noguitracer/0 
switch between traditional text-based and window-based debugging. The 
tracer is activated using the trace/0, spy/1 
or menu items from PceEmacs or the Prolog Navigator.
 
- The Prolog Navigator
 Shows the file structure and structure inside the file. It allows for 
loading files, editing, setting spy points, etc.