582 lines
15 KiB
Prolog
582 lines
15 KiB
Prolog
/*************************************************************************
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* *
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* YAP Prolog *
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* *
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* Yap Prolog was developed at NCCUP - Universidade do Porto *
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* *
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* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
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* *
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**************************************************************************
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* *
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* File: utils.yap *
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* Last rev: 8/2/88 *
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* mods: *
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* comments: Some utility predicates available in yap *
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* *
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*************************************************************************/
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op(P,T,V) :-
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'$check_op'(P,T,V,op(P,T,V)),
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'$op'(P, T, V).
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'$check_op'(P,T,V,G) :-
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(
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var(P) ->
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'$do_error'(instantiation_error,G)
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;
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var(T) ->
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'$do_error'(instantiation_error,G)
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;
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var(V) ->
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'$do_error'(instantiation_error,G)
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;
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\+ integer(P) ->
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'$do_error'(type_error(integer,P),G)
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;
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\+ atom(T) ->
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'$do_error'(type_error(atom,T),G)
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;
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P < 0 ->
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'$do_error'(domain_error(out_of_range,P),G)
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;
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P > 1200 ->
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'$do_error'(domain_error(out_of_range,P),G)
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;
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\+ '$associativity'(T) ->
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'$do_error'(domain_error(operator_specifier,T),G)
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;
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'$check_op_name'(V,G)
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).
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'$associativity'(xfx).
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'$associativity'(xfy).
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'$associativity'(yfx).
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'$associativity'(yfy).
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'$associativity'(xf).
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'$associativity'(yf).
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'$associativity'(fx).
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'$associativity'(fy).
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'$check_op_name'(V,G) :-
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var(V), !,
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'$do_error'(instantiation_error,G).
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'$check_op_name'(V,_) :-
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atom(V), !.
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'$check_op_name'(M:A, G) :-
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(
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var(M) ->
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'$do_error'(instantiation_error,G)
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;
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var(A) ->
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'$do_error'(instantiation_error,G)
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;
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atom(M) ->
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'$check_op_name'(A, G)
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;
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'$do_error'(instantiation_error,G)
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).
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'$check_op_name'([A|As], G) :-
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'$check_op_name'(A, G),
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'$check_op_names'(As, G).
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'$check_op_names'([], _).
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'$check_op_names'([A|As], G) :-
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'$check_op_name'(A, G),
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'$check_op_names'(As, G).
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'$op'(P, T, M:[A|As]) :- !,
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'$current_module'(M),
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'$opl'(P, T, M, [A|As]).
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'$op'(P, T, [A|As]) :- !,
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'$opl'(P, T, M, [A|As]).
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'$op'(P, T, A) :-
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'$op2'(P,T,A).
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'$opl'(P, T, _, []).
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'$opl'(P, T, M, [A|As]) :-
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'$op2'(P, T, M:A),
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'$opl'(P, T, M, As).
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'$op2'(P,T,A) :-
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atom(A), !,
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'$opdec'(P,T,A,prolog).
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'$op2'(P,T,A) :-
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strip_module(A,M,N),
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'$opdec'(P,T,N,M).
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current_op(X,Y,V) :- var(V), !,
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'$current_module'(M),
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'$do_current_op'(X,Y,V,M).
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current_op(X,Y,M:Z) :- !,
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'$current_opm'(X,Y,Z,M).
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current_op(X,Y,Z) :-
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'$current_module'(M),
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'$do_current_op'(X,Y,Z,M).
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'$current_opm'(X,Y,Z,M) :-
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var(Z), !,
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'$do_current_op'(X,Y,Z,M).
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'$current_opm'(X,Y,M:Z,_) :- !,
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'$current_opm'(X,Y,Z,M).
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'$current_opm'(X,Y,Z,M) :-
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'$do_current_op'(X,Y,Z,M).
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'$do_current_op'(X,Y,Z,M) :-
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atom(Z), !,
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'$current_atom_op'(Z, M1, Prefix, Infix, Posfix),
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( M1 = prolog -> true ; M1 = M ),
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(
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'$get_prefix'(Prefix, X, Y)
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;
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'$get_infix'(Infix, X, Y)
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;
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'$get_posfix'(Posfix, X, Y)
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).
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'$do_current_op'(X,Y,Z,M) :-
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'$current_op'(Z, M1, Prefix, Infix, Posfix),
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( M1 = prolog -> true ; M1 = M ),
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(
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'$get_prefix'(Prefix, X, Y)
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;
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'$get_infix'(Infix, X, Y)
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;
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'$get_posfix'(Posfix, X, Y)
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).
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'$get_prefix'(Prefix, X, Y) :-
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Prefix > 0,
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X is Prefix /\ 0xfff,
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(
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0x2000 /\ Prefix =:= 0x2000
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->
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Y = fx
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;
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Y = fy
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).
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'$get_infix'(Infix, X, Y) :-
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Infix > 0,
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X is Infix /\ 0xfff,
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(
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0x3000 /\ Infix =:= 0x3000
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->
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Y = xfx
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;
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0x1000 /\ Infix =:= 0x1000
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->
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Y = xfy
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;
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Y = yfx
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).
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'$get_posfix'(Posfix, X, Y) :-
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Posfix > 0,
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X is Posfix /\ 0xfff,
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(
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0x1000 /\ Posfix =:= 0x1000
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->
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Y = xf
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;
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Y = yf
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).
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%%% Operating System utilities
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unix(V) :- var(V), !,
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'$do_error'(instantiation_error,unix(V)).
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unix(argv(L)) :- '$is_list_of_atoms'(L,L), !, '$argv'(L).
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unix(argv(V)) :-
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'$do_error'(type_error(atomic,V),unix(argv(V))).
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unix(cd) :- cd('~').
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unix(cd(V)) :- var(V), !,
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'$do_error'(instantiation_error,unix(cd(V))).
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unix(cd(A)) :- atomic(A), !, cd(A).
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unix(cd(V)) :-
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'$do_error'(type_error(atomic,V),unix(cd(V))).
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unix(environ(X,Y)) :- '$do_environ'(X,Y).
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unix(getcwd(X)) :- getcwd(X).
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unix(shell(V)) :- var(V), !,
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'$do_error'(instantiation_error,unix(shell(V))).
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unix(shell(A)) :- atom(A), !, '$shell'(A).
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unix(shell(V)) :-
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'$do_error'(type_error(atomic,V),unix(shell(V))).
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unix(system(V)) :- var(V), !,
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'$do_error'(instantiation_error,unix(system(V))).
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unix(system(A)) :- atom(A), !, system(A).
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unix(system(V)) :-
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'$do_error'(type_error(atom,V),unix(system(V))).
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unix(shell) :- sh.
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unix(putenv(X,Y)) :- '$putenv'(X,Y).
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'$is_list_of_atoms'(V,_) :- var(V),!.
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'$is_list_of_atoms'([],_) :- !.
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'$is_list_of_atoms'([H|L],L0) :- !,
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'$check_if_head_may_be_atom'(H,L0),
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'$is_list_of_atoms'(L,L0).
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'$is_list_of_atoms'(H,L0) :-
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'$do_error'(type_error(list,H),unix(argv(L0))).
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'$check_if_head_may_be_atom'(H,_) :-
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var(H), !.
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'$check_if_head_may_be_atom'(H,_) :-
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atom(H), !.
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'$check_if_head_may_be_atom'(H,L0) :-
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'$do_error'(type_error(atom,H),unix(argv(L0))).
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'$do_environ'(X, Y) :-
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var(X), !,
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'$do_error'(instantiation_error,unix(environ(X,Y))).
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'$do_environ'(X, Y) :- atom(X), !,
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'$getenv'(X,Y).
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'$do_environ'(X, Y) :-
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'$do_error'(type_error(atom,X),unix(environ(X,Y))).
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putenv(Na,Val) :-
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'$putenv'(Na,Val).
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getenv(Na,Val) :-
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'$getenv'(Na,Val).
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%%% Saving and restoring a computation
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save(A) :- var(A), !,
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'$do_error'(instantiation_error,save(A)).
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save(A) :- atom(A), !, name(A,S), '$save'(S).
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save(S) :- '$save'(S).
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save(A,_) :- var(A), !,
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'$do_error'(instantiation_error,save(A)).
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save(A,OUT) :- atom(A), !, name(A,S), '$save'(S,OUT).
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save(S,OUT) :- '$save'(S,OUT).
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save_program(A) :- var(A), !,
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'$do_error'(instantiation_error,save_program(A)).
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save_program(A) :- atom(A), !, name(A,S), '$save_program'(S).
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save_program(S) :- '$save_program'(S).
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save_program(A, G) :- var(A), !,
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'$do_error'(instantiation_error,save_program(A,G)).
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save_program(A, G) :- var(G), !,
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'$do_error'(instantiation_error,save_program(A,G)).
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save_program(A, G) :- \+ callable(G), !,
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'$do_error'(type_error(callable,G),save_program(A,G)).
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save_program(A, G) :-
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( atom(A) -> name(A,S) ; A = S),
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recorda('$restore_goal',G,R),
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'$save_program'(S),
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erase(R),
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fail.
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save_program(_,_).
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restore(A) :- var(A), !,
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'$do_error'(instantiation_error,restore(A)).
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restore(A) :- atom(A), !, name(A,S), '$restore'(S).
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restore(S) :- '$restore'(S).
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prolog :-
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'$live'.
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%%% current ....
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recordaifnot(K,T,R) :-
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recorded(K,T,R), % force non-det binding to R.
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'$still_variant'(R,T),
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!,
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fail.
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recordaifnot(K,T,R) :-
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recorda(K,T,R).
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recordzifnot(K,T,R) :-
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recorded(K,T,R),
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'$still_variant'(R,T),
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!,
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fail.
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recordzifnot(K,T,R) :-
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recordz(K,T,R).
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current_atom(A) :- % check
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atom(A), !.
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current_atom(A) :- % generate
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'$current_atom'(A).
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current_atom(A) :- % generate
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'$current_wide_atom'(A).
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atom_concat(X,Y,At) :-
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(
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nonvar(X), nonvar(Y)
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->
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atom_concat([X,Y],At)
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;
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atom(At) ->
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'$atom_contact_split'(At,X,Y)
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;
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var(At) ->
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'$do_error'(instantiation_error,atom_concat(X,Y,At))
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;
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'$do_error'(type_error(atom,At),atomic_concant(X,Y,At))
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).
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'$atom_contact_split'(At,X,Y) :-
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nonvar(X), !,
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atom_codes(At, Codes),
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atom_codes(X, Xs),
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lists:append(Xs,Ys,Codes),
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atom_codes(Y, Ys).
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'$atom_contact_split'(At,X,Y) :-
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nonvar(Y), !,
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atom_codes(At, Codes),
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atom_codes(Y, Ys),
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once(lists:append(Xs,Ys,Codes)),
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atom_codes(X, Xs).
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'$atom_contact_split'(At,X,Y) :-
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atom_codes(At, Codes),
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lists:append(Xs, Ys, Codes),
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atom_codes(X, Xs),
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atom_codes(Y, Ys).
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atomic_list_concat(L,At) :-
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atomic_concat(L, At).
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atomic_concat(X,Y,At) :-
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(
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nonvar(X), nonvar(Y)
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->
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atomic_concat([X,Y],At)
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;
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atom(At) ->
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atom_length(At,Len),
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'$atom_contact_split'(At,X,Y)
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;
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number(At) ->
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'$number_contact_split'(At,X,Y)
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;
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var(At) ->
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'$do_error'(instantiation_error,atomic_concat(X,Y,At))
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;
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'$do_error'(type_error(atomic,At),atomic_concant(X,Y,At))
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).
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'$number_contact_split'(At,X,Y) :-
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nonvar(X), !,
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number_codes(At, Codes),
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name(X, Xs),
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lists:append(Xs,Ys,Codes),
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name(Y, Ys).
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'$number_contact_split'(At,X,Y) :-
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nonvar(Y), !,
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number_codes(At, Codes),
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name(Y, Ys),
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once(lists:append(Xs,Ys,Codes)),
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name(X, Xs).
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'$number_contact_split'(At,X,Y) :-
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number_codes(At, Codes),
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lists:append(Xs, Ys, Codes),
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name(X, Xs),
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name(Y, Ys).
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sub_atom(At, Bef, Size, After, SubAt) :-
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% extract something from an atom
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atom(At), integer(Bef), integer(Size), !,
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'$sub_atom_extract'(At, Bef, Size, After, SubAt).
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sub_atom(At, Bef, Size, After, SubAt) :-
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% extract subatom from an atom
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atom(At), atom(SubAt), !,
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'$do_sub_atom_fetch'(At, Bef, Size, After, SubAt, 0).
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sub_atom(At, Bef, Size, After, SubAt) :-
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atom(At), !,
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atom_codes(At, Atl),
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'$sub_atom2'(Bef, Atl, Size, After, SubAt, sub_atom(At, Bef, Size, After, SubAt)).
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sub_atom(At, Bef, Size, After, SubAt) :-
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var(At), !,
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'$do_error'(instantiation_error,sub_atom(At, Bef, Size,After, SubAt)).
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sub_atom(At, Bef, Size, After, SubAt) :-
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\+ atom(At), !,
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'$do_error'(type_error(atom,At),sub_atom(At, Bef, Size,After, SubAt)).
|
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|
|
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'$do_sub_atom_fetch'(At, Bef, Size, After, SubAt, I0) :-
|
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'$sub_atom_fetch'(At, Bef1, Size, After1, SubAt, I0),
|
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(
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Bef = Bef1, After = After1
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;
|
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Next is Bef1+1,
|
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'$do_sub_atom_fetch'(At, Bef, Size, After, SubAt, Next)
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).
|
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|
|
|
|
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'$sub_atom2'(Bef, Atl, Size, After, SubAt, ErrorTerm) :-
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var(Bef), !,
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'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm).
|
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'$sub_atom2'(Bef, Atl, Size, After, SubAt, ErrorTerm) :-
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'$sub_atom_get_subchars'(Bef, Atl, NewAtl),
|
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'$sub_atom3'(Size, After, SubAt, NewAtl, ErrorTerm).
|
|
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% if SubAt is bound, the rest is deterministic.
|
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'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
|
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nonvar(SubAt), !,
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'$sub_atom_needs_atom'(SubAt,ErrorTerm),
|
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'$sub_atom_needs_int'(Size,ErrorTerm),
|
|
'$sub_atom_needs_int'(After,ErrorTerm),
|
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atom_codes(SubAt,Atls),
|
|
'$$_length1'(Atls, 0, Size),
|
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'$sub_atom_get_subchars_and_match'(Size, Atl, Atls, NAtl),
|
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'$$_length1'(NAtl,0,After).
|
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% SubAt is unbound, but Size is bound
|
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'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
|
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nonvar(Size), !,
|
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'$sub_atom_needs_int'(Size,ErrorTerm),
|
|
'$sub_atom_needs_int'(After,ErrorTerm),
|
|
'$sub_atom_get_subchars_and_match'(Size, Atl, SubAts, NAtl),
|
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'$$_length1'(NAtl,0,After),
|
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atom_codes(SubAt,SubAts).
|
|
% SubAt and Size are unbound, but After is bound.
|
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'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
|
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nonvar(After), !,
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'$sub_atom_needs_int'(After,ErrorTerm),
|
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'$sub_atom_get_last_subchars'(Atl,SubAts,After,Total,Size),
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Total >= After,
|
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atom_codes(SubAt,SubAts).
|
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% SubAt, Size, and After are unbound.
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'$sub_atom3'(Size, After, SubAt, Atl, _) :-
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'$$_length1'(Atl,0,Len),
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'$sub_atom_split'(Atl,Len,SubAts,Size,_,After),
|
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atom_codes(SubAt,SubAts).
|
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|
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% Bef is unbound, so we've got three hypothesis
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% ok: in the best case we just try to find SubAt in the original atom.
|
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'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm) :-
|
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nonvar(SubAt), !,
|
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'$sub_atom_needs_atom'(SubAt, ErrorTerm),
|
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atom_codes(SubAt,SubAts),
|
|
'$sub_atom_search'(SubAts, Atl, 0, Bef, AfterS),
|
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'$$_length1'(SubAts, 0, Size),
|
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'$$_length1'(AfterS, 0, After).
|
|
% ok: in the second best case we just get rid of the tail
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'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm) :-
|
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nonvar(After), !,
|
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'$sub_atom_needs_int'(After, ErrorTerm),
|
|
'$sub_atom_get_last_subchars'(Atl,SubAt0,After,Total,Size0),
|
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Total >= After,
|
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'$sub_atom_split'(SubAt0,Size0,_,Bef,SubAts,Size),
|
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atom_codes(SubAt,SubAts).
|
|
% ok: just do everything
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'$sub_atombv'(Bef, Size, After, SubAt, Atl, _) :-
|
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'$$_length1'(Atl, 0, Len),
|
|
'$sub_atom_split'(Atl,Len,_,Bef,Atls2,Len2),
|
|
'$sub_atom_split'(Atls2,Len2,SubAts,Size,_,After),
|
|
atom_codes(SubAt,SubAts).
|
|
|
|
'$sub_atom_search'([], AfterS, BefSize, BefSize, AfterS).
|
|
'$sub_atom_search'([C|SubAts], [C|Atl], BefSize, BefSize, AfterS) :-
|
|
'$sub_atom_search2'(SubAts, Atl, AfterS).
|
|
'$sub_atom_search'([C|SubAts], [_|Atl], BefSize, BefSizeF, AfterS) :-
|
|
NBefSize is BefSize+1,
|
|
'$sub_atom_search'([C|SubAts], Atl, NBefSize, BefSizeF, AfterS).
|
|
|
|
'$sub_atom_search2'([], AfterS, AfterS).
|
|
'$sub_atom_search2'([C|SubAts], [C|Atl], AfterS) :-
|
|
'$sub_atom_search2'(SubAts, Atl, AfterS).
|
|
|
|
'$sub_atom_get_subchars'(0, Atl, Atl) :- !.
|
|
'$sub_atom_get_subchars'(I0, [_|Atl], NAtl) :-
|
|
I is I0-1,
|
|
'$sub_atom_get_subchars'(I, Atl, NAtl).
|
|
|
|
'$sub_atom_get_subchars'(0, Atl, [], Atl) :- !.
|
|
'$sub_atom_get_subchars'(I0, [C|Atl], [C|L], NAtl) :-
|
|
I is I0-1,
|
|
'$sub_atom_get_subchars'(I, Atl, L, NAtl).
|
|
|
|
'$sub_atom_get_subchars_and_match'(0, Atl, [], Atl) :- !.
|
|
'$sub_atom_get_subchars_and_match'(I0, [C|Atl], [C|Match], NAtl) :-
|
|
I is I0-1,
|
|
'$sub_atom_get_subchars_and_match'(I, Atl, Match, NAtl).
|
|
|
|
'$sub_atom_check_length'([],0).
|
|
'$sub_atom_check_length'([_|L],N1) :-
|
|
N1 > 0,
|
|
N is N1-1,
|
|
'$sub_atom_check_length'(L,N).
|
|
|
|
'$sub_atom_get_last_subchars'([],[],_,0,0).
|
|
'$sub_atom_get_last_subchars'([C|Atl],SubAt,After,Total,Size) :-
|
|
'$sub_atom_get_last_subchars'(Atl,SubAt0,After,Total0,Size0),
|
|
Total is Total0+1,
|
|
( Total > After ->
|
|
Size is Size0+1, SubAt = [C|SubAt0]
|
|
;
|
|
Size = Size0, SubAt = SubAt0
|
|
).
|
|
|
|
'$sub_atom_split'(Atl,After,[],0,Atl,After).
|
|
'$sub_atom_split'([C|Atl],Len,[C|Atls],Size,NAtl,After) :-
|
|
Len1 is Len-1,
|
|
'$sub_atom_split'(Atl,Len1,Atls,Size0,NAtl,After),
|
|
Size is Size0+1.
|
|
|
|
'$sub_atom_needs_int'(V,_) :- var(V), !.
|
|
'$sub_atom_needs_int'(I,_) :- integer(I), I >= 0, !.
|
|
'$sub_atom_needs_int'(I,ErrorTerm) :- integer(I), !,
|
|
'$do_error'(domain_error(not_less_than_zero,I),ErrorTerm).
|
|
'$sub_atom_needs_int'(I,ErrorTerm) :-
|
|
'$do_error'(type_error(integer,I),ErrorTerm).
|
|
|
|
'$sub_atom_needs_atom'(V,_) :- var(V), !.
|
|
'$sub_atom_needs_atom'(A,_) :- atom(A), !.
|
|
'$sub_atom_needs_atom'(A,ErrorTerm) :-
|
|
'$do_error'(type_error(atom,A),ErrorTerm).
|
|
|
|
'$singletons_in_term'(T,VL) :-
|
|
'$variables_in_term'(T,[],V10),
|
|
'$sort'(V10, V1),
|
|
'$non_singletons_in_term'(T,[],V20),
|
|
'$sort'(V20, V2),
|
|
'$subtract_lists_of_variables'(V2,V1,VL).
|
|
|
|
'$subtract_lists_of_variables'([],VL,VL).
|
|
'$subtract_lists_of_variables'([_|_],[],[]) :- !.
|
|
'$subtract_lists_of_variables'([V1|VL1],[V2|VL2],VL) :-
|
|
V1 == V2, !,
|
|
'$subtract_lists_of_variables'(VL1,VL2,VL).
|
|
'$subtract_lists_of_variables'([V1|VL1],[V2|VL2],[V2|VL]) :-
|
|
'$subtract_lists_of_variables'([V1|VL1],VL2,VL).
|
|
|
|
simple(V) :- var(V), !.
|
|
simple(A) :- atom(A), !.
|
|
simple(N) :- number(N).
|
|
|
|
callable(V) :- var(V), !, fail.
|
|
callable(V) :- atom(V), !.
|
|
callable(V) :- functor(V,_,Ar), Ar > 0.
|
|
|
|
nth_instance(Key,Index,Ref) :-
|
|
nonvar(Key), var(Index), var(Ref), !,
|
|
recorded(Key,_,Ref),
|
|
'$nth_instance'(_,Index,Ref).
|
|
nth_instance(Key,Index,Ref) :-
|
|
'$nth_instance'(Key,Index,Ref).
|
|
|
|
nth_instance(Key,Index,T,Ref) :-
|
|
nonvar(Key), var(Index), var(Ref), !,
|
|
recorded(Key,T,Ref),
|
|
'$nth_instance'(_,Index,Ref).
|
|
nth_instance(Key,Index,T,Ref) :-
|
|
'$nth_instance'(Key,Index,Ref),
|
|
instance(Ref,T).
|
|
|
|
nb_current(GlobalVariable, Val) :-
|
|
var(GlobalVariable), !,
|
|
'$nb_current'(GlobalVariable),
|
|
nb_getval(GlobalVariable, Val).
|
|
nb_current(GlobalVariable, Val) :-
|
|
nb_getval(GlobalVariable, Val).
|
|
|