[Prolog related questions],
failure-slice: Are you wondering why Prolog loops so often? Read
this reply and others using a failure-slice. Failure slices can also be used to determine a lower bound for the number of inferences:
Prolog prologue is our attempt to make Prolog systems a bit more uniform.
Help put dcgs on a safe normative basis
now! Use SO just for
factual questions around.
Features of good Prolog code?
And now to purity. Whose mind is not touched by such beauty?
Xs = 
; Xs = [_A],
; Xs = [_A,_B],
; Xs = [_A,_B,_C],
dif(X,_A), dif(X,_B), dif(X,_C)
The fine print
Close-voted/Closed/deleted questions. Can you help to reformulate/reopen them? SO rules are sometimes a little difficult to apply.
A prologue for Prolog
Still here? So I can tell you: my handle is vocative.