% File : foreach.pl % Author : Neng-Fa Zhou % Updated: June 2009, updated Dec. 2009, updated Sep. 2010 % Purpose: an interpreter of foreach/2-10 and list comprehension /************************************************************************/ :- yap_flag(unknown,error). :- ensure_loaded(actionrules). :- op(560,xfy,[..,to,downto]). :- op(700,xfx,[subset,notin,in,@=]). :- use_module(library(lists)). /* test:- L=[1,2,3],foreach(I in L, writeln(I)),fail. test:- foreach(I in 1..10,format("~d ",I)),fail. test:- foreach(I in 1..2..10,format("~d ",I)),fail. % step = 2 test:- foreach(I in 10.. -1.. 1,format("~d ",I)),fail. % step = -1 test:- foreach((A,N) in ([a,b],1..2),writeln(A=N)),fail. test:- L=[1,2,3],foreach(I in L, ac(S,0), S^1 is S^0+I),writeln(S),fail. test:- T=f(1,2,3),functor(T,_,N),foreach(I in 1..N,ac(S,0),(S^1 is S^0+T[I])),writeln(S),fail. test:- L=[1,2,3],foreach(I in L, ac1(C,[]), C^0=[I|C^1]),writeln(C),fail. test:- foreach(I in [1,2], J in [a,b], ac(L,[]),L^1=[(I,J)|L^0]),writeln(L),fail. test:- foreach(I in [1,2], J in [a,b], ac1(L,[]),L^0=[(I,J)|L^1]),writeln(L),fail. test:- foreach(T in ([a,b],1..2),writeln(T)),fail. test:- foreach(F in 1.0..0.2..1.5,format("~1f ",F)),fail. test:- L @= [I : I in 1..10],writeln(L),fail. test:- L @= [I : I in 1..2..10],writeln(L),fail. test:- L @= [I : I in 10..-1..1],writeln(L),fail. test:- L @=[X : X in 1..5],writeln(L),fail. test:- L @= [1 : X in 1..5],writeln(L),fail. test:- L @= [Y : X in 1..5],writeln(L),fail. test:- L @= [Y : X in 1..5,[Y]],writeln(L),fail. test:- L @=[(A,I): (A,I) in ([a,b],1..2)],writeln(L),fail. test:- L @= [Y : X in [1,2,3], [Y], Y is -X],writeln(L),fail. test:- L @=[(A,I): A in [a,b], I in 1..2],writeln(L),fail. test:- L @=[(A,I): (A,I) in ([a,b],1..2)],writeln(L),fail. test. */ Lhs @= Rhs, Rhs=[(T:I)|Is], I=(_ in _) => % list comprehension '$change_list_comprehension_to_foreach'(T,I,Is,CallForeach,L), call(CallForeach), L @= Lhs. Lhs @= Rhs, Lhs=[(T:I)|Is], I=(_ in _) => % list comprehension '$change_list_comprehension_to_foreach'(T,I,Is,CallForeach,L), call(CallForeach), L @= Rhs. A^Indexes @= Exp => % array access '$aget'(A,Indexes,T), Exp @= T. Exp @= A^Indexes => % array access '$aget'(A,Indexes,T), Exp @= T. Lhs @= Rhs => Lhs=Rhs. '$change_list_comprehension_to_foreach'(T,I,Is,CallForeach,L):- '$retrieve_list_comp_lvars_goal'(Is,LocalVars1,Goal1,Is1), (nonvar(T),T=_^_-> % array access LocalVars=[TempVar|LocalVars1], (Goal1==true-> Goal=(TempVar@=T,L^0=[TempVar|L^1]) ; Goal=(Goal1->(TempVar@=T,L^0=[TempVar|L^1]);L^0=L^1) ) ; LocalVars=LocalVars1, (Goal1==true-> Goal=(L^0=[T|L^1]) ; Goal=(Goal1->L^0=[T|L^1];L^0=L^1) ) ), append(Is1,[LocalVars,ac1(L,[]),Goal],Is2), CallForeach=..[foreach,I|Is2]. '$retrieve_list_comp_lvars_goal'([],LocalVars,Goal,Is) => LocalVars=[],Goal=true,Is=[]. '$retrieve_list_comp_lvars_goal'([E|Es],LocalVars,Goal,Is),E = (_ in _) => Is=[E|IsR], '$retrieve_list_comp_lvars_goal'(Es,LocalVars,Goal,IsR). '$retrieve_list_comp_lvars_goal'([LVars,G],LocalVars,Goal,Is),LVars=[] => Is=[],LocalVars=LVars,G=Goal. '$retrieve_list_comp_lvars_goal'([LVars,G],LocalVars,Goal,Is),LVars=[_|_] => Is=[],LocalVars=LVars,G=Goal. '$retrieve_list_comp_lvars_goal'([LVars],LocalVars,Goal,Is),LVars=[_|_] => Is=[],LocalVars=LVars,Goal=true. '$retrieve_list_comp_lvars_goal'([LVars],LocalVars,Goal,Is),LVars=[] => Is=[],LocalVars=LVars,Goal=true. '$retrieve_list_comp_lvars_goal'([G],LocalVars,Goal,Is) => Is=[],LocalVars=[],G=Goal. '$retrieve_list_comp_lvars_goal'(Args,_LocalVars,_Goal,_Is) => throw(illegal_arguments(list_comprehension(Args))). foreach(A1,A2,A3,A4,A5,A6,A7,A8,A9,A10):- foreach_aux((A1,A2,A3,A4,A5,A6,A7),A8,A9,A10). foreach(A1,A2,A3,A4,A5,A6,A7,A8,A9):- foreach_aux((A1,A2,A3,A4,A5,A6),A7,A8,A9). foreach(A1,A2,A3,A4,A5,A6,A7,A8):- foreach_aux((A1,A2,A3,A4,A5),A6,A7,A8). foreach(A1,A2,A3,A4,A5,A6,A7):- foreach_aux((A1,A2,A3,A4),A5,A6,A7). foreach(A1,A2,A3,A4,A5,A6):- foreach_aux((A1,A2,A3),A4,A5,A6). foreach(A1,A2,A3,A4,A5):- foreach_aux((A1,A2),A3,A4,A5). foreach(A1,A2,A3,A4):- foreach_aux(A1,A2,A3,A4). foreach_aux(A1,A2,A3,A4):- (A2=(_ in _); A2=(_,_)),!, % iterator foreach_aux((A1,A2),A3,A4). foreach_aux(A1,A2,A3,A4):- foreach_check_accumulators(A3),!, interp_foreach_with_acs(A1,A2,A3,A4). foreach_aux(A1,A2,A3,A4):- foreach_check_accumulators(A2),!, interp_foreach_with_acs(A1,A3,A2,A4). foreach_aux(A1,A2,A3,A4):- throw(illegal_arguments(foreach(A1,A2,A3,A4))). foreach(A1,A2,A3):- foreach_aux(A1,A2,A3). foreach_aux(A1,A2,A3):- (A2=(_ in _); A2=(_,_)),!, interp_foreach((A1,A2),true,[],A3,[],[],_). foreach_aux(A1,A2,A3):- foreach_check_accumulators(A2),!, interp_foreach_with_acs(A1,[],A2,A3). foreach_aux(A1,A2,A3):- foreach_check_lvars(A2),!, interp_foreach(A1,true,A2,A3,[],[],_). foreach(Iterators,Goal):- interp_foreach(Iterators,true,[],Goal,[],[],_). interp_foreach_with_acs(Iterators,LVars,Accumulators,Goal):- init_accumulators(Accumulators,ACs0),!, interp_foreach(Iterators,true,LVars,Goal,[],ACs0,ACs), fin_accumulators(Accumulators,ACs0,ACs). interp_foreach_with_acs(Iterators,LVars,Accumulators,Goal):- throw(illegal_arguments(foreach(Iterators,LVars,Accumulators,Goal))). interp_foreach((I,Is),IsRest,LVars,Goal,Map,ACs0,ACs):-!, (IsRest==true->IsRest1=Is;IsRest1=(Is,IsRest)), interp_foreach(I,IsRest1,LVars,Goal,Map,ACs0,ACs). interp_foreach(Pattern in D,IsRest,LVars,Goal,Map,ACs0,ACs):- interp_foreach_term_instance(D,D1,Map), (var(D1)->handle_exception(instantiation_error,foreach);true), interp_foreach_in(Pattern,D1,IsRest,LVars,Goal,Map,ACs0,ACs). interp_foreach(true,true,LVars,Goal,Map,ACs0,ACs):-!, foreach_copy_accumulators(ACs0,ACs), interp_foreach_term_instance(Goal,Goal1,LVars,Map,_,ACs0,ACs), call(Goal1). interp_foreach(true,Is,LVars,Goal,Map,ACs0,ACs):- interp_foreach(Is,true,LVars,Goal,Map,ACs0,ACs). interp_foreach_in(Var,(L..Step..U),IsRest,LVars,Goal,Map,ACs0,ACs) => (var(Var)->true;throw(wrong_loop_variable(Var))), (foreach_lookup_map(Var,_,Map)->throw(duplicate_loop_variable(Var));true), L1 is L, U1 is U, Step1 is Step, foreach_range(Var,L1,U1,Step1,IsRest,LVars,Goal,Map,ACs0,ACs). interp_foreach_in(Var,L..U,IsRest,LVars,Goal,Map,ACs0,ACs) => (var(Var)->true;throw(wrong_loop_variable(Var))), (foreach_lookup_map(Var,_,Map)->throw(duplicate_loop_variable(Var));true), L1 is L, U1 is U, foreach_range(Var,L1,U1,1,IsRest,LVars,Goal,Map,ACs0,ACs). interp_foreach_in(_,[],IsRest,LVars,Goal,Map,ACs0,ACs) => ACs=ACs0. interp_foreach_in(E,D,IsRest,LVars,Goal,Map,ACs0,ACs):-true ::: term_variables(E,EVars), (member(Var,EVars),foreach_lookup_map(Var,_,Map),!,throw(duplicate_loop_variable(Var));true), foreach_pattern_in(E,D,IsRest,LVars,Goal,Map,ACs0,ACs). foreach_range(_Var,L,U,Step,_IsRest,_LVars,_Goal,_Map,ACs0,ACs),Step>0,L>U => ACs0=ACs. foreach_range(_Var,L,U,Step,_IsRest,_LVars,_Goal,_Map,ACs0,ACs),Step<0,L ACs0=ACs. foreach_range(Var,L,U,Step,IsRest,LVars,Goal,Map,ACs0,ACs) => interp_foreach(IsRest,true,LVars,Goal,[(Var,L)|Map],ACs0,ACs1), L1 is L+Step, foreach_range(Var,L1,U,Step,IsRest,LVars,Goal,Map,ACs1,ACs). foreach_pattern_in(_Pattern,D,_IsRest,_LVars,_Goal,_Map,_ACs0,_ACs),var(D) => handle_exception(instantiation_error,foreach). foreach_pattern_in(Pattern,D,IsRest,LVars,Goal,Map,ACs0,ACs),D=[_|_] => foreach_pattern_in_list(Pattern,D,IsRest,LVars,Goal,Map,ACs0,ACs). foreach_pattern_in(Pattern,D,IsRest,LVars,Goal,Map,ACs0,ACs) => foreach_simu_collection_to_tuples(D,Tuples), foreach_pattern_in_list(Pattern,Tuples,IsRest,LVars,Goal,Map,ACs0,ACs). foreach_pattern_in_list(_Pattern,Lst,_IsRest,_LVars,_Goal,_Map,_ACs0,_ACs),var(Lst) => handle_exception(instantiation_error,foreach). foreach_pattern_in_list(_Pattern,[],_IsRest,_LVars,_Goal,_Map,ACs0,ACs) => ACs0=ACs. foreach_pattern_in_list(Pattern,[E|Es],IsRest,LVars,Goal,Map,ACs0,ACs) => (foreach_update_map(Pattern,E,Map,Map1)-> interp_foreach(IsRest,true,LVars,Goal,Map1,ACs0,ACs1) ; ACs0=ACs1), foreach_pattern_in_list(Pattern,Es,IsRest,LVars,Goal,Map,ACs1,ACs). foreach_pattern_in_list(_Pattern,Lst,_IsRest,_LVars,_Goal,_Map,_ACs0,_ACs):-true ::: handle_exception(type_error(list,Lst),foreach). foreach_update_map(Var,E,Map0,Map):-var(Var),!,Map=[(Var,E)|Map0]. foreach_update_map(Pattern,E,Map0,Map):-atomic(Pattern),!,E==Pattern,Map=Map0. foreach_update_map(Pattern,E,Map0,Map):-nonvar(E), functor(Pattern,F,N), functor(E,F,N), foreach_update_map(Pattern,E,Map0,Map,1,N). foreach_update_map(_Pattern,_E,Map0,Map,I,N):-I>N,!,Map=Map0. foreach_update_map(Pattern,E,Map0,Map,I,N):- arg(I,Pattern,Ti), arg(I,E,Ei), foreach_update_map(Ti,Ei,Map0,Map1), I1 is I+1, foreach_update_map(Pattern,E,Map1,Map,I1,N). interp_foreach_term_instance(Term,Term1,Map):- interp_foreach_term_instance(Term,Term1,[],Map,_,[],[]). % Replace loop variables with their values; rename local variables; % replace inputs and outputs in recurrences: A^0 is input and A^1 is output. interp_foreach_term_instance(Term,NTerm,LVars,Map,NMap,_ACs0,_ACs):-var(Term),!, (foreach_lookup_map(Term,NTerm,Map)->NMap=Map; membchk(Term,LVars)->NMap=[(Term,NTerm)|Map]; NTerm=Term,NMap=Map). interp_foreach_term_instance(Term,NTerm,_LVars,Map,NMap,_ACs0,_ACs):-atomic(Term),!, NTerm=Term,NMap=Map. interp_foreach_term_instance(Term^Tail,NTerm,_LVars,Map,NMap,ACs0,_ACs):- var(Term),Tail==0, foreach_lookup_map(Term,NTerm,ACs0),!, NMap=Map. interp_foreach_term_instance(Term^Tail,NTerm,_LVars,Map,NMap,_ACs0,ACs):- var(Term),Tail==1, foreach_lookup_map(Term,NTerm,ACs),!, NMap=Map. interp_foreach_term_instance([E|Es],Lst,LVars,Map,NMap,ACs0,ACs):-!, Lst=[E1|Es1], interp_foreach_term_instance(E,E1,LVars,Map,Map1,ACs0,ACs), interp_foreach_term_instance(Es,Es1,LVars,Map1,NMap,ACs0,ACs). interp_foreach_term_instance(Term,NTerm,_LVars,Map,NMap,_ACs0,_ACs):- is_array(Term),!, NTerm=Term,NMap=Map. interp_foreach_term_instance(Term,NTerm,_LVars,Map,NMap,_ACs0,_ACs):- is_hashtable(Term),!, NTerm=Term,NMap=Map. interp_foreach_term_instance(Term,NTerm,LVars,Map,NMap,ACs0,ACs):- functor(Term,F,N), functor(NTerm,F,N), interp_foreach_term_instance(Term,NTerm,LVars,Map,NMap,1,N,ACs0,ACs). interp_foreach_term_instance(_Term,_NTerm,_LVars,Map,NMap,I,N,_,_):-I>N,!, NMap=Map. interp_foreach_term_instance(Term,NTerm,LVars,Map,NMap,I,N,ACs0,ACs):- arg(I,Term,A), arg(I,NTerm,NA), interp_foreach_term_instance(A,NA,LVars,Map,Map1,ACs0,ACs), I1 is I+1, interp_foreach_term_instance(Term,NTerm,LVars,Map1,NMap,I1,N,ACs0,ACs). init_accumulators(ac1(Name,_),ACs):-!, ACs=[(Name,_)]. init_accumulators(ac(Name,Init),ACs):-!, ACs=[(Name,Init)]. init_accumulators(Accumulators,ACs):-Accumulators=[_|_], init_accumulator_lst(Accumulators,ACs). init_accumulator_lst([],ACs):-!,ACs=[]. init_accumulator_lst([ac1(Name,_)|Accumulators],ACs):-!, ACs=[(Name,_)|ACsR], init_accumulator_lst(Accumulators,ACsR). init_accumulator_lst([ac(Name,Init)|Accumulators],ACs):- ACs=[(Name,Init)|ACsR], init_accumulator_lst(Accumulators,ACsR). fin_accumulators(ac1(Name,Fin),[(_,Init)],[(_,Val)]):-!, Name=Init,Fin=Val. fin_accumulators(ac(Name,_),_,[(_,Val)]):-!, Name=Val. fin_accumulators(Accumulators,ACs0,ACs):-Accumulators=[_|_], fin_accumulator_lst(Accumulators,ACs0,ACs). fin_accumulator_lst([],_,_). fin_accumulator_lst([ac1(Name,Fin)|Accumulators],[(_,Init)|ACs0],[(_,Val)|ACs]):-!, Fin=Val, Name=Init, fin_accumulator_lst(Accumulators,ACs0,ACs). fin_accumulator_lst([ac(Name,_)|Accumulators],[_|ACs0],[(_,Val)|ACs]):- Name=Val, fin_accumulator_lst(Accumulators,ACs0,ACs). foreach_copy_accumulators([],ACs):-!, ACs=[]. foreach_copy_accumulators([(Name,_)|ACs0],ACs):- ACs=[(Name,_)|ACs1], foreach_copy_accumulators(ACs0,ACs1). foreach_check_lvars([]):-true ::: true. foreach_check_lvars([X|Xs]):- var(X) ::: foreach_check_lvars(Xs). foreach_check_lvars(Xs):-true ::: throw(illegal_local_variables(Xs)). foreach_check_accumulators(ac1(_,_)):-!. foreach_check_accumulators(ac(_,_)):-!. foreach_check_accumulators(Accumulators):-Accumulators=[_|_], foreach_check_accumulator_lst(Accumulators). foreach_check_accumulator_lst([]). foreach_check_accumulator_lst([X|_]):-var(X),!,fail. foreach_check_accumulator_lst([ac(_,_)|L]):-!, foreach_check_accumulator_lst(L). foreach_check_accumulator_lst([ac1(_,_)|L]):- foreach_check_accumulator_lst(L). foreach_lookup_map(Term,NTerm,[(Term1,NTerm1)|_]):-Term==Term1,!, NTerm=NTerm1. foreach_lookup_map(Term,NTerm,[_|Map]):- foreach_lookup_map(Term,NTerm,Map). foreach_simu_collection_to_tuples((C1,C2,C3),Tuples) ?=> foreach_collection_to_lst(C1,L1), foreach_collection_to_lst(C2,L2), foreach_collection_to_lst(C3,L3),!, (foreach_simu_collection_to_tuples3(L1,L2,L3,Tuples)->true; handle_exception(wrong_collection_in_foreach,(C1,C2,C3))). foreach_simu_collection_to_tuples((C1,C2),Tuples) ?=> foreach_collection_to_lst(C1,L1), foreach_collection_to_lst(C2,L2),!, (foreach_simu_collection_to_tuples2(L1,L2,Tuples)->true; handle_exception(wrong_collection_in_foreach,(C1,C2))). foreach_simu_collection_to_tuples(CTuple,_) => handle_exception(wrong_collection_in_foreach,CTuple). foreach_collection_to_lst([],L) => L=[]. foreach_collection_to_lst(C,L),C=[_|_] => L=C. foreach_collection_to_lst((B1..Step..B2),L) => NB1 is B1, NB2 is B2, NStep is Step, foreach_eval_range(NB1,NB2,NStep,L). foreach_collection_to_lst((B1..B2),L) => NB1 is B1, NB2 is B2, foreach_eval_range(NB1,NB2,1,L). foreach_collection_to_lst(CTuple,L),CTuple=(_,_) => foreach_simu_collection_to_tuples(CTuple,L). foreach_collection_to_lst(Collection,_L) => handle_exception(wrong_collection_in_foreach,Collection). foreach_eval_range(B1,B2,Step,L),Step>0,B1>B2 => L=[]. foreach_eval_range(B1,B2,Step,L),Step<0,B1 L=[]. foreach_eval_range(B1,B2,Step,L) => L=[B1|LR], NB1 is B1+Step, foreach_eval_range(NB1,B2,Step,LR). foreach_simu_collection_to_tuples3([],[],[],Tuples) => Tuples=[]. foreach_simu_collection_to_tuples3([X1|L1],[X2|L2],[X3|L3],Tuples) => Tuples=[(X1,X2,X3)|TuplesR], foreach_simu_collection_to_tuples3(L1,L2,L3,TuplesR). foreach_simu_collection_to_tuples2([],[],Tuples) => Tuples=[]. foreach_simu_collection_to_tuples2([X1|L1],[X2|L2],Tuples) => Tuples=[(X1,X2)|TuplesR], foreach_simu_collection_to_tuples2(L1,L2,TuplesR).