%% A very simple example of "old-style" coinduction:
%% p( t ) should succeed for every term t, but the number of answers is
%% infinite.

:- coinductive0 p/1.

p( X ) :-  q( X ).

q( X ) :-  r( X ).

r( X ) :-  p( X ).


:- topl q/0.

q :-  p( hoho ).