% Example of handling records: load, add, remove, save
:-dynamic(student/3).

% load the student records from a file called students.plg
load_students:-consult('students.plg'), 
	tell('students.plg.bak'), listing(student), told.

% list students
list_students:-listing(student).

% admit a student, supply SId number and Name, record with no classes
admit(SId, Name):-assert(student(SId,Name, [])),
	write(student(SId, Name, [])), write(' added.').

% remove student record from data - supply an Id, a name or both
dismiss(SId, Name):-retract(student(SId, Name, List)), 
	write(student(SId, Name, List)), write(' deleted.').

% save modified records in place of old ones.
save_students:-tell('students.plg'), listing(student), told.