Welcome to SWI-Prolog (Multi-threaded, Version 5.6.20)
Copyright (c) 1990-2006 University of Amsterdam.
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to redistribute it under certain conditions.
Please visit http://www.swi-prolog.org for details.

For help, use ?- help(Topic). or ?- apropos(Word).


Yes

Yes

Command? Echo turned on; prompt turned off

Command: cut(x, 10, y)
x: No such pipe

Command: weld(x, y)
x: No such pipe

Command: weld(a, x)
x: No such pipe

Command: cut(a, 5, b)
b: pipe already exists

Command: cut(a, 10, a2)
Cut is too long!

Command: cut(x, 10, a2)
x: No such pipe

Command: trim(a, 15)
Cut is too long!

Command: trim(x, 15)
x: No such pipe

Command: weld(a, c)
Can't weld: differing diameters

Command: done

Yes

% halt