func_style/2

func_style.pl

:- op(1200, xfx, ::-).
:- op(  30,  fx,   ^).

term_expansion(Head ::- Body0, Head :- Body1) :-
	func_style(Body0, Body1).

replace_hats(X, X, Vars, Vars, (Z,Z)) :- var(X), !.
replace_hats(**, V, [V|Vars], Vars, (Z,Z)) :- !.
replace_hats(^X, V, Vars1, Vars2, ([P|Preds],Z)) :- !,
	replace_hats(X, P, [V|Vars1], Vars2, (Preds,Z)).

replace_hats(Fun1, Fun2, Vars1, Vars2, Preds) :- !,
	Fun1 =.. [A|Args1],
	merge_hats(Args1, Args2, Vars1, Vars2, Preds),
	Fun2 =.. [A|Args2].

merge_hats([], [], Vars, Vars, (Z,Z)) :- !.
merge_hats([Arg1|Args1], [Arg2|Args2], Vars1, Vars3, (Preds1,Z2)) :- !,
	replace_hats(Arg1, Arg2, Vars1, Vars2, (Preds1,Z1)),
	merge_hats(Args1, Args2, Vars2, Vars3, (Preds2,Z2)),
	Z1 = Preds2.

func_style((X1, Y1), (X2, Y2)) :- !,
	func_style(X1, X2),
	func_style(Y1, Y2).

func_style((X1; Y1), (X2; Y2)) :- !,
	func_style(X1, X2),
	func_style(Y1, Y2).

list_to_goals([P], P) :- !.
list_to_goals([P|Preds], (Goals, P)) :- list_to_goals(Preds, Goals).

func_style(X1, X3) :-
	replace_hats(X1, X2, [], [], (Preds,[])),
	list_to_goals([X2|Preds], X3).