While writing this answer I stumbled over Prolog's weird output when given multiple lines of input.
Does anyone know why here some true are followed by a point and two newlines, while others do not have the point and no newline? Also why are there additional newlines for the last two false. results?
Finally when removing the double newlines between the input statements the following error occurs:
true.
true Unknown action: f (h for help)
Action? Unknown action: f (h for help)
