1/* Part of LogicMOO Base An Implementation a MUD server in SWI-Prolog
    2% ===================================================================
    3% File 'dcg_meta.pl'
    4% Purpose: An Implementation in SWI-Prolog of certain debugging tools
    5% Maintainer: Douglas Miles
    6% Contact: $Author: logicmoo@gmail.com ;
    7% Version: 'logicmoo_util_bugger.pl' 1.0.0
    8% Revision:  $Revision: 1.1 $
    9% Revised At:   $Date: 2002/07/11 21:57:28 $
   10% ===================================================================
   11*/
   12:- module(dcg_meta,[
   13         do_dcg_util_tests/0,
   14         isVar/1,
   15         isQVar/1,
   16         isVarOrVAR/1,
   17         file_eof//0,
   18         charvar/1,
   19         cspace//0,
   20         cwhite//0,
   21         mw//1,
   22         bx/1,
   23         zalwayz//1,
   24         zalwayz/1,
   25         one_blank//0,
   26         set_dcg_meta_reader_options/2,
   27         phrase_from_stream_nd/2,
   28         parse_meta_term/3,
   29         read_string_until//2,
   30         read_string_until_no_esc//2,
   31         dcgOneOrMore//1,
   32         dcgOptional//1,
   33         dcgZeroOrMore//1,
   34         dcgOptionalGreedy//1,
   35         dcgAnd//2,
   36         dcgAnd//3,
   37         dcgAnd//4,
   38         dcgMust//1,
   39         %dumpList/1,
   40         dcgSeqLen//1,
   41         dcgOr//2,
   42         dcgNot//1,
   43         theString//1,
   44         theString//2,
   45         theText//1,
   46         theCode//1,
   47         dcgLenBetween/4,
   48         notrace_catch_fail/1,
   49         notrace_catch_fail/3,
   50         % unit test functions
   51         do_dcgTest/3,
   52         do_dcgTest_startsWith/3,
   53         decl_dcgTest_startsWith/2,
   54         decl_dcgTest_startsWith/3,
   55         decl_dcgTest/2,
   56         decl_dcgTest/3,
   57         dcgReorder/4
   58	 ]).

   67:- set_module(class(library)).   68
   69:- meta_predicate track_stream(*,0).   70:- meta_predicate read_string_until(*,*,//,?,?).   71:- meta_predicate read_string_until_pairs(*,//,?,?).   72
   73:- system:use_module(library(listing)).   74:- system:use_module(library(lists)).   75:- system:use_module(library(time)).   76:- system:use_module(library(readutil)).   77
   78
   79:- dynamic(t_l:dcg_meta_reader_options/2).   80:- thread_local(t_l:dcg_meta_reader_options/2).   81
   82set_dcg_meta_reader_options(N,V):- retractall(t_l:dcg_meta_reader_options(N,_)),asserta(t_l:dcg_meta_reader_options(N,V)).
   83get_dcg_meta_reader_options(N,V):- t_l:dcg_meta_reader_options(N,V).
   84
   85
   86
   87% Portray ASCII code sequences (for debugging DCGs)
   88user:portray(List):- compound(List),compound_name_arity([_,_],F,A),compound_name_arity(List,F,A),
   89    List=[H|_],integer(H),H>9,user_portray_dcg_seq(List).
   90
   91user_portray_dcg_seq(List):- \+ is_list(List),!,between(32,1,Len),length(Left,Len),append(Left,_,List), ground(Left),!,
   92   catch(atom_codes(W,Left),_,fail),format("|~w ___|",[W]).
   93user_portray_dcg_seq(List):- is_codelist(List), catch(atom_codes(Atom,List),_,fail),length(List,Len),
   94  (Len < 32 -> format("`~w`",[Atom]) ;
   95    (length(Left,26),append(Left,_Rest,List),format(atom(Print),"~s",[Left]),format("|~w ... |",[Print]))).
   96
   97
   98% :- ensure_loaded(library(logicmoo_utils)).
   99% :- ensure_loaded(library(logicmoo_util_strings)).
  100
  101:- meta_predicate bx(0).  102:- meta_predicate expr_with_text(*,2,*,*,*).  103:- meta_predicate locally_setval(*,*,0).  104:- meta_predicate notrace_catch_fail(0).  105:- meta_predicate notrace_catch_fail(0,?,0).  106:- meta_predicate phrase_from_buffer_codes(//,*).  107:- meta_predicate phrase_from_buffer_codes_nd(//,*).  108:- meta_predicate phrase_from_pending_stream(*,//,*).  109:- meta_predicate phrase_from_pending_stream(//,?).  110:- meta_predicate phrase_from_stream_lazy_part(//,*).  111:- meta_predicate read_string_until(*,*,//,?,?).  112:- meta_predicate read_string_until_no_esc(*,//,?,?).  113:- meta_predicate read_string_until_pairs(*,//,?,?).  114:- meta_predicate zalwayz(//,?,?).  115:- meta_predicate(zalwayz(0)).  116:- meta_predicate track_stream(*,0).  117:- meta_predicate always_b(//,?,?).  118:- meta_predicate phrase_from_stream_nd(//,+).  119:- meta_predicate read_string_until(*,//,?,?).  120
  121
  122:- meta_predicate dcgLeftOfMid(?,//,?,?).  123:- meta_predicate dcgLeftMidRight(//,//,//,?,?).  124
  125:- meta_predicate dcgAnd(//,//,//,//,?,?).  126:- meta_predicate dcgAnd(//,//,//,?,?).  127:- meta_predicate dcgAnd(//,//,?,?).  128:- meta_predicate dcgAndRest(//,*,*,*).  129:- meta_predicate dcgBoth(//,//,*,*).  130:- meta_predicate dcgIgnore(//,?,?).  131:- meta_predicate dcgLeftOf(//,*,*,*).  132:- meta_predicate dcgMust(//,?,?).  133:- meta_predicate dcgMidLeft(//,*,//,*,?).  134:- meta_predicate dcgNot(//,?,?).  135:- meta_predicate dcgOnce(//,?,?).  136:- meta_predicate dcgOnceOr(//,//,?,?).  137:- meta_predicate dcgOneOrMore(//,?,*).  138:- meta_predicate dcgOptional(//,?,?).  139:- meta_predicate dcgOptionalGreedy(//,?,?).  140:- meta_predicate dcgOr(//,//,//,//,//,?,?).  141:- meta_predicate dcgOr(//,//,//,//,?,?).  142:- meta_predicate dcgOr(//,//,//,?,?).  143:- meta_predicate dcgOr(//,//,?,?).  144:- meta_predicate dcgReorder(//,//,?,?).  145:- meta_predicate dcgStartsWith(//,?,?).  146:- meta_predicate dcgStartsWith0(//,?,*).  147:- meta_predicate dcgStartsWith1(//,?,?).  148:- meta_predicate dcgTraceOnFailure(0).  149:- meta_predicate dcgWhile(?,//,?,?).  150:- meta_predicate dcgZeroOrMore(//,?,*).  151:- meta_predicate decl_dcgTest(?,?).  152:- meta_predicate decl_dcgTest(?,?,?).  153:- meta_predicate decl_dcgTest_startsWith(?,?,?).  154:- meta_predicate do_dcgTest(*,//,0).  155:- meta_predicate do_dcgTest_startsWith(?,//,?).  156:- meta_predicate suggestVar(2,*,?).  157:- meta_predicate theAll(//,?,?).  158:- meta_predicate theCode(?,?,?).  159
  160% :- meta_predicate decl_dcgTest(?,//).
  161% :- meta_predicate decl_dcgTest_startsWith(?,*,0).
  162% :- meta_predicate decl_dcgTest(?,//,0).
  163% :- meta_predicate theCode(0,*,*).
  164
  165% this is a backwards compatablity block for SWI-Prolog 6.6.6
  166
  167:- if(current_prolog_flag(dialect,swi)).  168:- dynamic(double_quotes_was_in_dcg/1).  169:- current_prolog_flag(double_quotes,WAS),asserta(double_quotes_was_in_dcg(WAS)).  170:- retract(double_quotes_was_in_dcg(WAS)),set_prolog_flag(double_quotes,WAS).  171:- current_prolog_flag(double_quotes,WAS),asserta(double_quotes_was_in_dcg(WAS)).  172:- set_prolog_flag(double_quotes,string).  173:- endif.  174
  175isVarOrVAR(V):-var(V),!.
  176isVarOrVAR('$VAR'(_)).
  177isVar(V):- (isVarOrVAR(V);isQVar(V)),!.
  178isQVar(Cvar):-atom(Cvar),atom_concat('?',_,Cvar).
  179
  180:- dynamic
  181   decl_dcgTest/2,
  182   decl_dcgTest/3,
  183   decl_dcgTest_startsWith/2,
  184   decl_dcgTest_startsWith/3.  185
  186
  187decl_dcgTest(X,Y):- nonvar(Y),!,do_dcgTest(X,Y,true).
  188decl_dcgTest(X,Y,Z):- nonvar(Y),!,do_dcgTest(X,Y,Z).
  189decl_dcgTest_startsWith(X,Y):- nonvar(Y),!,do_dcgTest(X,dcgStartsWith(Y),true).
  190decl_dcgTest_startsWith(X,Y,Z):- nonvar(Y),!,do_dcgTest(X,dcgStartsWith(Y),Z).
  191% ========================================================================
  192% getWhatnot helpers
  193% ========================================================================
  194
  195getText([],[]).
  196getText(L,Txt):-member([txt|Txt],L),!.
  197getText([L|List],Text):-getText(L,Text1),getText(List,Text2),append(Text1,Text2,Text),!.
  198getText(F,S):-compound_name_arity(F,_,3),arg(2,F,S),!.
  199getText(S,S).
  200
  201
  202% ========================================================================
  203% theWhatnot helpers  (parses contents of terminals)
  204% ========================================================================
  205:- style_check(-discontiguous).  206
  207
  208
  209equals_text(S,Data):- is_list(Data),member([txt,S0],Data),!,equals_text(S,S0).
  210equals_text(S,S):- !.
  211%equals_text(S,S0):- var(S),var(S0),!,S=S0.
  212equals_text(S,S0):- var(S0),text_to_string(S,S0),!.
  213equals_text(S,S0):- var(S),text_to_string(S0,S),!.
  214equals_text(S,S0):- text_to_string(S,SS),text_to_string(S0,SS).
  215
  216decl_dcgTest("this is text",theText([this,is,text])).
  217
  218% Text
  219
  220theText(Text) --> {Text==[],!},[].
  221theText([S|Text]) --> {nonvar(S),!},theText0(S),!,theText(Text).
  222
  223theText([S|Text]) --> theText0(S),theText(Text).
  224theText([]) --> [].
  225
  226%theText([S|Text],[S0|TextData],More):- member([txt,S0|TextData],Data),equals_text(S,S0),append(Text,More,TextData).
  227
  228%  dtrace, do_dcgTest_startsWith("this is text", dcg_meta:dcgStartsWith1(theText(["this"])), true) .
  229
  230% Looser text test?
  231theText0(_,W,_):- W==[],!,fail.
  232theText0(S) --> {atomic(S),atom_concat('"',Right,S),atom_concat(New,'"',Right),!},theText(New).
  233theText0(S) --> {atomic(S),concat_atom([W1,W2|List],' ',S),!},theText([W1,W2|List]).
  234theText0(S) --> {!}, [Data],{equals_text(S,Data)}.
  235
  236
  237
  238
  239decl_dcgTest("this is a string",theString("this is a string")).
  240theString(String) --> theString(String, " ").
  241
  242atomic_to_string(S,S):- string(S),!.
  243atomic_to_string(S,Str):-sformat(Str,'~w',[S]).
  244
  245atomics_to_string_str(L,S,A):-catch(atomics_to_string(L,S,A),_,fail).
  246atomics_to_string_str(L,S,A):-atomics_to_string_str0(L,S,A).
  247
  248atomics_to_string_str0([],_Sep,""):-!.
  249atomics_to_string_str0([S],_Sep,String):-atom(S),!,string_to_atom(String,S).
  250atomics_to_string_str0([S],_Sep,S):- string(S),!.
  251atomics_to_string_str0([S|Text],Sep,String):-
  252   atomic_to_string(S,StrL),
  253   atomics_to_string_str0(Text,Sep,StrR),!,
  254   new_a2s([StrL,StrR],Sep,String).
  255
  256% theString(String,Sep) --> [S|Text], {atomic_list_concat_catch([S|Text],Sep,String),!}.
  257theString(String,Sep) --> [S|Text], {atomics_to_string_str([S|Text],Sep,String),!}.
  258
  259decl_dcgTest_startsWith([a,b|_],theCode(X=1),X==1).
  260decl_dcgTest_startsWith("anything",theCode(X=1),X==1).
  261decl_dcgTest("",theCode(X=1),X==1).
  262theCode(Code) --> [],{Code}.
  263
  264
  265decl_dcgTest([a,b|C],theAll([a,b|C])).
  266% theAll(X)--> X.
  267theAll(X, B, C) :- var(X),X=B,C=[],!.
  268theAll(X, B, C) :- phrase(X, B, C).
  269
  270decl_dcgTest([a,b|C],theRest(X),X==[a,b|C]).
  271theRest(X, X, []).
  272
  273
  274
  275theName(Var,S,_) :-getText(S,Text),suggestVar(=,Text,Var),!.
  276
  277%suggestVar(_,Subj,Subj2):-makeName(Subj,Subj2),!.
  278
  279suggestVar(_Gensym,Subj,Subj):-var(Subj),!.%,true,!.
  280suggestVar(_Gensym,Subj,_Subj2):-var(Subj),!.%,true,!.
  281suggestVar(Gensym,[W|ORDS],Subj):-!,ignore((once((nonvar(ORDS),toPropercase([W|ORDS],Proper),concat_atom(['Hypothetic'|Proper],'-',Suj),call(Gensym,Suj,SubjSl),ignore(SubjSl=Subj))))),!.
  282%suggestVar(Gensym,[W|ORDS],Subj):-!,ignore(quietly_pfs(once((nonvar(ORDS),concat_atom(['?'|[W|ORDS]],'',Suj),call(Gensym,Suj,SubjSl),toUppercase(SubjSl,SubjS),ignore(SubjS=Subj))))),!.
  283suggestVar(_Gensym,[],_):-!.%suggestVar(gensym,[A],Subj),!.
  284suggestVar(Gensym,A,Subj):-suggestVar(Gensym,[A],Subj),!.
  285
  286
  287
  288%makeName(Subj,Subj2):-toCreate(Subj,hypotheticDenotation(Subj,_,string(Words))),!,makeName(Words,Subj2),!.
  289makeName(A,A):-!.
  290makeName(Subj,Subj2):-var(Subj),!,term_to_atom(Subj,Atom),makeName(['Hypothetic',Atom],Subj2),!.
  291makeName([],Subj2):-!,makeName(_Subj,Subj2),!.
  292makeName(Subj,Subj2):-atom(Subj),atom_concat('?',Sub2,Subj),!,makeName(Sub2,Subj2),!.
  293makeName(A,Subj):-atom(A),!,makeName([A],Subj),!.
  294makeName([W|ORDS],Subj):-nonvar(ORDS),!,toPropercase([W|ORDS],PCASE),concat_atom(['Hypothetic'|PCASE],'-',Suj),gensym(Suj,Subj),!.
  295
  296leastOne([_CO|_LSS]).
  297
  298% ========================================================================
  299% dcgWhatnot helpers  (meta interprets)
  300% ========================================================================
  301
  302% TODO: when using the DCG to generate instead of test it will move the C before the P
  303% dcgReorder(P,C) --> P, C.
  304:- export(dcgReorder//2).  305dcgReorder(P, C, B, E):- phrase(P, B, D), phrase(C, D, E).
  306
  307:- export(dcgSeq//2).  308dcgSeq(X,Y,[S0,S1|SS],E):-phrase((X,Y),[S0,S1|SS],E).
  309
  310:- export(dcgBoth//2).  311dcgBoth(DCG1,DCG2,S,R) :- append(L,R,S),phrase(DCG1,L,[]),once(phrase(DCG2,L,[])).
  312
  313dcgAnd(DCG1,DCG2,DCG3,DCG4,S,E) :- phrase(DCG1,S,E),phrase(DCG2,S,E),phrase(DCG3,S,E),phrase(DCG4,S,E).
  314dcgAnd(DCG1,DCG2,DCG3,S,E) :- phrase(DCG1,S,E),phrase(DCG2,S,E),phrase(DCG3,S,E).
  315dcgAnd(DCG1,DCG2,S,E) :- phrase(DCG1,S,E),phrase(DCG2,S,E).
  316dcgOr(DCG1,DCG2,DCG3,DCG4,DCG5,S,E) :- phrase(DCG1,S,E);phrase(DCG2,S,E);phrase(DCG3,S,E);phrase(DCG4,S,E);phrase(DCG5,S,E).
  317dcgOr(DCG1,DCG2,DCG3,DCG4,S,E) :- phrase(DCG1,S,E);phrase(DCG2,S,E);phrase(DCG3,S,E);phrase(DCG4,S,E).
  318dcgOr(DCG1,DCG2,DCG3,S,E) :- phrase(DCG1,S,E);phrase(DCG2,S,E);phrase(DCG3,S,E).
  319dcgOr(DCG1,DCG2,S,E) :- phrase(DCG1,S,E);phrase(DCG2,S,E).
  320dcgOnceOr(DCG1,DCG2,S,E) :- phrase(DCG1,S,E)->true;phrase(DCG2,S,E).
  321dcgNot(DCG2,S,E) :- \+ phrase(DCG2,S,E).
  322dcgIgnore(DCG2,S,E) :- ignore(phrase(DCG2,S,E)).
  323dcgOnce(DCG2,S,E) :- once(phrase(DCG2,S,E)).
  324
  325dcgWhile(True,Frag)-->dcgAnd(dcgOneOrMore(True),Frag).
  326
  327dcgMust((DCG1,List),S,E) :- is_list(List),!,must((phrase(DCG1,S,SE),phrase(List,SE,E))).
  328dcgMust(DCG1,S,E) :- must(phrase(DCG1,S,E)).
  329
  330dcgSeqLen(Len, FB, END) :-
  331        length(CD, Len),
  332        '$append'(CD, END, FB).
  333
  334
  335% addtext a sofa is in here
  336% dcgLenBetween(_,_) --> [_].
  337dcgLenBetween(Start,Start) --> {!}, dcgSeqLen(Start),{!}.
  338dcgLenBetween(Start,End, FB, END) :- FB==[],!, ((Start>End -> between(End,Start,0) ; between(Start,End,0))),must(END=[]).
  339dcgLenBetween(Start,End) --> dcgOnceOr(dcgSeqLen(Start),({(Start>End -> Next is Start-1 ; Next is Start+1)},dcgLenBetween(Next,End))).
  340dcgLenBetween(Len, Start, End, FB, END) :-
  341       (length(CD, Start),
  342        '$append'(CD, END, FB)) -> ignore(End=Start) ;
  343        (
  344            (Start>End -> Next is Start-1 ; Next is Start+1),
  345            dcgLenBetween(Len, Next, End, FB, END)
  346        ).
  347
  348
  349
  350
  351dcgOneOrMore(True) --> True,dcgZeroOrMore(True),{!}.
  352
  353dcgZeroOrMore(True) --> True,{!},dcgZeroOrMore(True),{!}.
  354dcgZeroOrMore(_True) -->[].
  355
  356dcgLeftOf(Mid,[Left|T],S,[MidT|RightT]):-append([Left|T],[MidT|RightT],S),phrase(Mid,MidT),phrase([Left|T],_LeftT).
  357
  358
  359dcgLeftOfMid([Left|T],Mid,S,[MidT|RightT]):-append([Left|T],[MidT|RightT],S),phrase(Mid,MidT),phrase([Left|T],_LeftT).
  360
  361dcgLeftMidRight(Left,Mid,Right) --> dcgLeftOfMid(LeftL,Mid),{phrase(Left,LeftL,[])},Right.
  362
  363dcgMidLeft(Mid,Left,Right) --> dcgLeftOf(Mid,Left),Right.
  364
  365dcgNone --> [].
  366
  367dcgOptional(A)--> dcgOnce(dcgOr(A,dcgNone)).
  368
  369dcgOptionalGreedy(A)--> dcgOnce(dcgOr(A,dcgNone)).
  370
  371dcgTraceOnFailure(X):-once(X;(dtrace(X))).
  372
  373:- export(capitalized//1).  374capitalized([W|Text]) --> theText([W|Text]),{atom_codes(W,[C|_Odes]),is_upper(C)}.
  375
  376substAll(B,[],_R,B):-!.
  377substAll(B,[F|L],R,A):-subst(B,F,R,M),substAll(M,L,R,A).
  378
  379substEach(B,[],B):-!.
  380substEach(B,[F-R|L],A):-subst(B,F,R,M),substEach(M,L,A).
  381
  382dcgAndRest(TheType,_TODO,[S|MORE],[]) :- phrase(TheType,[S],[]),phrase(TheType,[S|MORE],[]).
  383
  384% =======================================================
  385% look ahead but ...
  386% =======================================================
  387
  388% 1) must be first in list
  389% 2) doesnt consume
  390% 3) sees as many items as needed
  391dcgStartsWith(TheType,SMORE,SMORE) :- phrase(TheType,SMORE,_).
  392
  393% tests for the above
  394decl_dcgTest_startsWith("this is text",dcgStartsWith(theText(["this","is"]))).
  395
  396
  397:- export(dcgStartsWith1//1).  398% 1) must be first in list
  399% 2) doesnt consume
  400% 3) sees only 1 item
  401dcgStartsWith1(TheType,[S|MORE],[S|MORE]) :- phrase(TheType,[S],[]).
  402
  403% tests for the above
  404decl_dcgTest_startsWith("this is text",dcgStartsWith1(theText(["this"]))).
  405
  406
  407% 1) must be first in list
  408% 2) consumes like theRest(...)
  409% 3) sees as many items as needed
  410dcgStartsWith0(TheType,SMORE,[]) :- phrase(TheType,SMORE,_).
  411
  412% tests for the above
  413decl_dcgTest("this is text",dcgStartsWith0(theText(["this",is]))).
  414
  415% =======================================================
  416% DCG Tester
  417% =======================================================
  418
  419:- export(do_dcg_util_tests/0).  420do_dcg_util_tests:-
  421   forall(decl_dcgTest(List,Phrase,Call),'@'((do_dcgTest(List,Phrase,Call)),dcg_meta)),
  422   forall(decl_dcgTest_startsWith(List,Phrase,Call),'@'((do_dcgTest_startsWith(List,Phrase,Call)),dcg_meta)).
  423
  424
  425do_dcgTest(Input,DCG,Call):- to_word_list(Input,List),OTEST=do_dcgTest(Input,DCG,Call),copy_term(DCG:OTEST,CDCG:TEST),
  426   once((phrase(DCG,List,Slack),Call,(Slack==[]->dmsg(passed(CDCG,TEST,OTEST));dmsg(warn(Slack,OTEST))))).
  427do_dcgTest(Input,DCG,Call):- dmsg(warn(failed(DCG, do_dcgTest(Input,DCG,Call)))).
  428
  429
  430do_dcgTest_startsWith(Input,DCG,Call):- to_word_list(Input,List),OTEST=do_dcgTest(Input,DCG,Call),copy_term(DCG:OTEST,CDCG:TEST),
  431   once((phrase(DCG,List,Slack),Call,(Slack==[]->wdmsg(warn(CDCG,TEST,OTEST));dmsg(passed(CDCG,TEST,OTEST))))).
  432do_dcgTest_startsWith(Input,DCG,Call):- wdmsg(warn(failed(DCG, do_dcgTest_startsWith(Input,DCG,Call)))).
  433
  434
  435decl_dcgTest(List,Phrase,true):-decl_dcgTest(List,Phrase).
  436decl_dcgTest_startsWith(List,Phrase,true):-decl_dcgTest_startsWith(List,Phrase).
  437
  438
  439
  440% :-source_location(File,_Line),module_property(M,file(File)),!,forall(current_predicate(M:F/A),M:export(F/A)).
  441
  442
  443
  444
  445%dumpList(B):- currentContext(dumpList,Ctx),dumpList(Ctx,B).
  446dumpList(_,AB):-dmsg(dumpList(AB)),!.
  447
  448dumpList(_,[]):-!.
  449%dumpList(Ctx,[A|B]):-!,fmt(Ctx,A),dumpList(Ctx,B),!.
  450%dumpList(Ctx,B):-fmt(Ctx,dumpList(B)).
  451
  452% this is a backwards compatablity block for SWI-Prolog 6.6.6
  453:- if(current_prolog_flag(dialect,swi)).  454:- retract(double_quotes_was_in_dcg(WAS)),set_prolog_flag(double_quotes,WAS).  455:- endif.  456
  457
  458optional(X) --> cwhite, !, optional(X).
  459optional(X) --> X,!, owhite.
  460optional(_) --> [].
  461optional(O,X) --> {debug_var(X,O),append_term(X,O,XO)},!,optional(XO).
  462
  463mw(X) --> cspace,!, mw(X).
  464mw(X) --> X,!, owhite.
  465
  466owhite --> {quietly_pfs(nb_current('$dcgm_whitespace',preserve))},!.
  467owhite --> cwhite.
  468owhite --> [].
  469
  470
  471
  472% cwhite --> comment_expr(S,I,CP),!,{assert(t_l:'$last_comment'('$COMMENT'(S,I,CP)))},!,owhite.
  473cwhite --> cspace,!,owhite.
  474cwhite --> {quietly_pfs(nb_current('$dcgm_comments',consume))},file_comment_expr(CMT),!,{assert(t_l:'$last_comment'(CMT))},!,owhite.
  475cwhite --> {quietly_pfs(nb_current('$dcgm_whitespace',preserve))}, !, {fail}.
  476
  477cspace --> [C], {nonvar(C),charvar(C),!,C\==10,bx(C =< 32)}.
  478
  479charvar(C):- integer(C)-> true; (writeln(charvar(C)),dumpST,writeln(charvar(C)),only_debug(break),fail).
  480
  481one_blank --> [C],!,{C =< 32}.
  482
  483:- meta_predicate(file_meta_with_comments(2,+,+,-)).  484:- meta_predicate(file_meta_with_comments0(2,+,+,-)).  485%file_meta_with_comments(Pred, O) --> [], {clause(t_l:'$last_comment'(O),_,Ref),erase(Ref)},!.
  486/*
  487file_meta_with_comments(Pred, O, A, B) :-
  488 attvar(A),
  489 get_attr(A,pure_input,lazy_input(Stream, PrevPos, Pos, _)),!,
  490 file_meta_with_comments0(Pred, O, A, B).
  491*/
  492file_meta_with_comments(Pred, O, A, B) :-
  493 file_meta_with_comments0(Pred, O, A, B).
  494
  495file_meta_with_comments0(Pred, O) --> one_blank,!,file_meta_with_comments(Pred, O).  % WANT?
  496file_meta_with_comments0(_Pred, C) --> file_comment_expr(C),!.
  497file_meta_with_comments0(_Pred, EOF) --> file_eof,!,{end_of_file=EOF}.
  498
  499file_meta_with_comments0(Pred, Out,S,E):- append_term(Pred,Out,PredOut),
  500  \+ t_l:dcg_meta_reader_options(with_text,true),!,phrase(PredOut,S,E),!.
  501file_meta_with_comments0(Pred, Out,S,E):- append_term(Pred,O,PredO),
  502 expr_with_text(Out,PredO,O,S,E),!.
  503
  504file_comment_expr(C)--> {get_dcg_meta_reader_options(file_comment_reader,Pred), append_term(Pred,C,PredC)},PredC.
  505
  506read_string_until_no_esc(String,End)--> dcg_notrace(read_string_until(noesc,String,End)).
  507read_string_until(String,End)--> read_string_until(esc,String,End).
  508
  509read_string_until(_,[],eoln,S,E):- S==[],!,E=[].
  510read_string_until(esc,[C|S],End) --> `\\`,!, zalwayz(escaped_char(C)),!, read_string_until(esc,S,End),!.
  511read_string_until(_,[],End) --> End, !.
  512%read_string_until(Esc,[35, 36|S],HB) --> {kif_ok}, `&%`, !,read_string_until(Esc,S,HB),!.
  513read_string_until(Esc,[C|S],End) --> [C],!,read_string_until(Esc,S,End),!.
  514
  515
  516read_string_until_pairs([C|S],End) --> `\\`,!, zalwayz(escaped_char(C)),!, read_string_until_pairs(S,End).
  517read_string_until_pairs([],HB) --> HB, !.
  518read_string_until_pairs([C|S],HB) --> [C],read_string_until_pairs(S,HB).
  519
  520escaped_char(C) --> eoln,!,[C].
  521escaped_char(E) --> [C], {atom_codes(Format,[92,C]),format(codes([E|_]),Format,[])},!.
  522escaped_char(Code)  --> [C], {escape_to_char([C],Code)},!.
  523
  524escape_to_char(Txt,Code):- notrace_catch_fail((sformat(S,'_=`\\~s`',[Txt]),read_from_chars(S,_=[Code]))),!.
  525
  526zalwayz_debug:-!.
  527zalwayz_debug:- current_prolog_flag(zalwayz,debug).
  528
  529never_zalwayz(Goal):-
  530 locally(current_prolog_flag(zalwayz,false),Goal).
  531
  532zalwayz_zalwayz(Goal):-
  533 locally(current_prolog_flag(zalwayz,debug),Goal).
  534
  535
  536zalwayz(G,H,T):- \+ zalwayz_debug, !, phrase(G,H,T).
  537zalwayz(G,H,T):- phrase(G,H,T),!.
  538zalwayz(G,H,T):- nb_current('$translation_stream',S),is_stream(S), \+ stream_property(S,tty(true)),!,always_b(G,H,T).
  539zalwayz(G,H,T):- always_b(G,H,T).
  540
  541only_debug(G):- \+ zalwayz_debug, !, nop(G),!.
  542only_debug(G):- !, call(G).
  543
  544%zalwayz(G):-  !, zalwayz(G).
  545zalwayz(G):- \+ zalwayz_debug, !, quietly_pfs(catch(G,_,fail)),!.
  546zalwayz(G):- must(G).
  547%zalwayz(P,S,L):-  !, zalwayz(P,S,L).
  548
  549always_b(G,H,T):- only_debug(break),H=[_|_],writeq(phrase_h(G,H,T)),dcg_print_start_of(H),writeq(phrase(G,H,T)),!,trace,ignore(rtrace(phrase(G,H,T))),!,quietly_pfs,dcg_print_start_of(H),writeq(phrase(G,H,T)), only_debug(break),!,fail.
  550always_b(G,H,T):- writeq(phrase(G,H,T)),dcg_print_start_of(H),writeq(phrase(G,H,T)),!,only_debug(trace),ignore(rtrace(phrase(G,H,T))),!,quietly_pfs,dcg_print_start_of(H),writeq(phrase(G,H,T)), break,!,fail.
  551
  552dcg_print_start_of(H):- (length(L,3000);length(L,300);length(L,30);length(L,10);length(L,1);length(L,0)),append(L,_,H),!,format('~NTEXT: ~s~n',[L]),!.
  553bx(CT2):- notrace_catch_fail(CT2,E,(writeq(E:CT2),only_debug(break))),!.
  554notrace_catch_fail(G,E,C):- catch(G,E,C),!.
  555notrace_catch_fail(G):- quietly_pfs(catch(G,_,fail)),!.
  556clean_fromt_ws([],[]).
  557clean_fromt_ws([D|DCodes],Codes):-
  558  ((\+ char_type(D,white), \+ char_type(D,end_of_line)) -> [D|DCodes]=Codes ; clean_fromt_ws(DCodes,Codes)).
  559
  560:- export(txt_to_codes/2).  561txt_to_codes(S,Codes):- quietly_pfs(is_stream(S)),!,stream_to_lazy_list(S,Codes),!.
  562txt_to_codes(AttVar,AttVarO):- quietly_pfs(attvar(AttVar)),!,AttVarO=AttVar.
  563% txt_to_codes([C|Text],[C|Text]):- integer(C),is_list(Text),!.
  564% txt_to_codes([C|Text],_):- atom(C),atom_length(C,1),!,throw(txt_to_codes([C|Text])).
  565txt_to_codes(Text,Codes):- notrace_catch_fail((text_to_string_safe(Text,String),!,string_codes(String,Codes))),!.
  566
  567phrase_from_pending_stream(Grammar, In):-
  568   remove_pending_buffer_codes(In,CodesPrev),
  569   phrase_from_pending_stream(CodesPrev, Grammar, In).
  570
  571phrase_from_pending_stream(CodesPrev,Grammar,In):- CodesPrev=[_,_|_],
  572   phrase(Grammar,CodesPrev,NewBuffer),!,
  573   append_buffer_codes(In,NewBuffer).
  574phrase_from_pending_stream(CodesPrev,Grammar,In):-
  575  b_setval('$translation_stream',In),
  576  read_codes_from_pending_input(In,Codes),!,
  577  ((quietly_pfs(is_eof_codes(Codes))) ->
  578     phrase_from_eof(Grammar, In);
  579     (append(CodesPrev,Codes,NewCodes), !,
  580       (phrase(Grammar, NewCodes, NewBuffer)
  581        -> append_buffer_codes(In,NewBuffer);
  582          phrase_from_pending_stream(NewCodes,Grammar,In)))).
  583
  584
  585dcg_notrace(G,S,E):- tracing -> setup_call_cleanup(notrace,phrase(G,S,E),trace); phrase(G,S,E).
  586my_lazy_list_location(Loc,S,S):- attvar(S), quietly_pfs(catch(lazy_list_location(Loc,S,S),_,fail)),!.
  587my_lazy_list_location(file(_,_,-1,-1))-->[].
  588
  589
  590track_stream(_In,G):- !,G.
  591track_stream(In,G):- \+ is_stream(In),!,G.
  592track_stream(In,G):-
  593   b_setval('$translation_stream',In),
  594   notrace_catch_fail(stream_position(In,Pos,Pos),_,true),
  595   character_count(In,Chars),
  596   stream_property(In,encoding(Was)),
  597   (setup_call_catcher_cleanup(
  598        nop(sset_stream(In,encoding(octet))),
  599        (ignore(notrace_catch_fail(line_count(In,Line),_,(Line = -1))),
  600         b_setval('$translation_line',Line-Chars),
  601           ((G),!)),
  602        Catcher,
  603        true)->true;Catcher=fail),
  604     track_stream_cleanup(Catcher,In,Was,Pos).
  605
  606track_stream_cleanup(Exit,In,Was,_Pos):-
  607 (Exit==exit ; Exit == (!)),!,
  608   sset_stream(In,encoding(Was)).
  609track_stream_cleanup(Catcher,In,Was,Pos):-
  610   sset_stream(In,encoding(Was)),
  611   ((nonvar(Pos),supports_seek(In))->stream_position(In,_Was,Pos);true),!,
  612   (compound(Catcher)-> (arg(1,Catcher,E),throw(E)) ; fail).
  613
  614sset_stream(S,P):- functor(P,F,A),functor(W,F,A), stream_property(S,W),!,
  615   (P=@=W->true;notrace(catch(set_stream(S,P),_,true))).
  616
  617
  618:- meta_predicate locally_setval(*,*,0).  619
  620locally_setval(Name,Value,Goal):-
  621 (nb_current(Name,Was)->true;Was=[]),
  622  b_setval(Name,Value),
  623  call(Goal),
  624  b_setval(Name,Was).
  625
  626
  627
  628:- thread_local(t_l:'$fake_buffer_codes'/2).  629
  630% parse_meta_stream(Pred,  +Stream, -Expr) is det.
  631%
  632% Parse Expression from a Stream
  633%
  634parse_meta_stream(Pred, S,Expr):-
  635  catch(
  636    parse_meta_stream_1(Pred, S,Expr),
  637    end_of_stream_signal(_Gram,S),
  638    Expr=end_of_file).
  639
  640parse_meta_stream_1(Pred, S,Expr):-
  641  phrase_from_stream_nd(file_meta_with_comments(Pred,Expr),S).
  642
  643
  644:- meta_predicate(quietly_pfs(0)).  645quietly_pfs(G):- !, call(G).
  646%quietly_pfs(G):- quietly(G).
  647%phrase_from_stream_nd(Grammar, In) :-  at_end_of_stream(In),trace,!,phrase_from_eof(Grammar, In).
  648
  649is_tty_alive(In):-
  650  stream_property(In,tty(true)),
  651  stream_property(In,mode(read)),
  652  stream_property(In,end_of_stream(not)).
  653
  654show_stream_info(In):-
  655     quietly_pfs((forall(stream_property(In,(BUF)),
  656    (writeq(show_stream_info(In,(BUF))),nl)))),!.
  657
  658phrase_from_stream_nd(Grammar,In):-
  659   quietly_pfs((peek_pending_codes(In,Codes)->Codes=[_,_|_],
  660   remove_pending_buffer_codes(In,_))),
  661   (phrase(Grammar,Codes,NewBuffer)-> append_buffer_codes(In,NewBuffer);(append_buffer_codes(In,Codes),fail)).
  662
  663phrase_from_stream_nd(Grammar, In) :- at_end_of_stream(In),
  664  peek_pending_codes(In,Pend),is_eof_codes(Pend),!,phrase_from_eof(Grammar, In). %
  665%phrase_from_stream_nd(Grammar, _) :- clause(t_l:'$last_comment'(I),_,Ref),I=Grammar,erase(Ref).
  666
  667phrase_from_stream_nd(Grammar, In) :- stream_property(In,tty(true)),!,
  668 repeat,
  669 (is_tty_alive(In)-> true ; throw(end_of_stream_signal(Grammar,In))),
  670 phrase_from_pending_stream(Grammar, In).
  671
  672phrase_from_stream_nd(Grammar, In) :-  supports_seek(In),
  673    ignore(notrace_catch_fail(sset_stream(In,buffer_size(819200)))),
  674    ignore(notrace_catch_fail(sset_stream(In,buffer_size(16384)))),
  675    ignore(notrace_catch_fail(sset_stream(In,encoding(octet)))),
  676    ignore(notrace_catch_fail(sset_stream(In,timeout(3.0)))),
  677    %sset_stream(In,buffer_size(5)), sset_stream(In,encoding(octet)), sset_stream(In,timeout(3.0)),sset_stream(In,type(text)),%sset_stream(In,buffer(false)),
  678   repeat, (at_end_of_stream(In)->(!,fail);true),
  679
  680    character_count(In, FailToPosition),
  681    ((phrase_from_stream_lazy_part(Grammar, In) *-> true ; (seek(In,FailToPosition,bof,_),!,fail))),!.
  682
  683phrase_from_stream_nd(Grammar, In) :- \+ supports_seek(In),!,
  684    if_debugging(sreader,show_stream_info(In)),
  685    read_stream_to_codes(In,Codes),
  686    b_setval('$translation_stream',In),
  687    append_buffer_codes(In,Codes),!,
  688    phrase_from_buffer_codes(Grammar,In).
  689
  690phrase_from_stream_nd(Grammar, In) :- stream_property(In,file_name(_Name)),!,
  691    if_debugging(sreader,show_stream_info(In)),
  692    read_stream_to_codes(In,Codes),
  693    b_setval('$translation_stream',In),
  694    append_buffer_codes(In,Codes),!,
  695    phrase_from_buffer_codes(Grammar,In).
  696
  697
  698phrase_from_stream_nd(Grammar, In) :- \+ supports_seek(In),!, phrase_from_pending_stream(Grammar, In).
  699%phrase_from_stream_nd(Grammar, In) :- b_setval('$translation_stream',In), quietly(phrase_from_stream_nd(Grammar, In)).
  700phrase_from_stream_nd(Grammar, In) :-  supports_seek(In),
  701    %sset_stream(In,buffer_size(819200)),sset_stream(In,buffer_size(16384)), sset_stream(In,encoding(octet)), sset_stream(In,timeout(3.0)),
  702    %sset_stream(In,buffer_size(5)), sset_stream(In,encoding(octet)), sset_stream(In,timeout(3.0)),sset_stream(In,type(text)),%sset_stream(In,buffer(false)),
  703    character_count(In, FailToPosition),
  704    ((phrase_from_stream_lazy_part(Grammar, In) -> true ; (seek(In,FailToPosition,bof,_),!,fail))),!.
  705
  706
  707phrase_from_stream_lazy_part(Grammar, In):-
  708    check_pending_buffer_codes(In),
  709    seek(In, 0, current, Prev),
  710    stream_to_lazy_list(In, List),
  711    nb_setval('$translation_line',Prev),!,
  712    phrase(Grammar, List, More) ->
  713    zalwayz((
  714       length(List,Used),!,
  715       length(More,UnUsed),!,
  716       if_debugging(sreader,wdmsg((Offset is Used - UnUsed + Prev))),
  717       bx(zalwayz(Offset is Used - UnUsed + Prev)),
  718       % dbginfo((Offset is Used - UnUsed + Prev)) ->
  719       seek(In,Offset,bof,_NewPos))).
  720%phrase_from_stream_lazy_part(Grammar, In):- phrase_from_file_part_c(Grammar, In).
  721
  722
  723peek_pending_codes(In,Codes):- peek_pending_codes0(In,Codes0),!,Codes=Codes0.
  724peek_pending_codes0(In,Codes):- (t_l:'$fake_buffer_codes'(In,DCodes);Codes=[]),!,clean_fromt_ws(DCodes,Codes).
  725
  726check_pending_buffer_codes(In):- peek_pending_codes(In,Codes),
  727  (Codes==[]->true;(throw(remove_pending_buffer_codes(In,Codes)))),!.
  728
  729clear_pending_buffer_codes:- forall(retract(t_l:'$fake_buffer_codes'(_In,_DCodes)),true).
  730remove_pending_buffer_codes(In,Codes):- retract(t_l:'$fake_buffer_codes'(In,DCodes)),!,clean_fromt_ws(DCodes,Codes).
  731remove_pending_buffer_codes(_In,[]). % for first read
  732
  733append_buffer_codes(In,Codes):- retract(t_l:'$fake_buffer_codes'(In,CodesPrev)),!,append(CodesPrev,Codes,NewCodes),assertz(t_l:'$fake_buffer_codes'(In,NewCodes)),!.
  734append_buffer_codes(In,Codes):- assertz(t_l:'$fake_buffer_codes'(In,Codes)),!.
  735
  736wait_on_input(In):- stream_property(In,end_of_stream(Not)),Not\==not,!.
  737wait_on_input(In):- repeat,wait_for_input([In],List,1.0),List==[In],!.
  738
  739read_codes_from_pending_input(In,Codes):- \+ is_stream(In),!,remove_pending_buffer_codes(In,Codes).
  740read_codes_from_pending_input(In,Codes):- stream_property(In,end_of_stream(Not)),Not\==not,!,(Not==at->Codes=end_of_file;Codes=[-1]).
  741read_codes_from_pending_input(In,Codes):-  stream_property(In, buffer(none)),!,
  742   repeat,
  743    once((wait_on_input(In),
  744    read_pending_codes(In,Codes,[]))),
  745    (Codes==[] -> (sleep(0.01),fail); true),!.
  746read_codes_from_pending_input(In,[Code|Codes]):-  get_code(In,Code),read_pending_codes(In,Codes,[]),!.
  747throw_reader_error(Error):- wdmsg(throw(reader_error(Error))),dumpST,wdmsg(throw(reader_error(Error))),throw(reader_error(Error)).
  748
  749supports_seek(In):- notrace_catch_fail(stream_property(In,reposition(true))).
  750% supports_seek(In):- quietly_pfs((notrace_catch_fail((notrace_catch_fail((seek(In, 1, current, _),seek(In, -1, current, _)),error(permission_error(reposition, stream, _), _Ctx),fail)),error(_,_),true))).
  751
  752phrase_from_eof(Grammar, _):- var(Grammar),!,unify_next_or_eof(Grammar),!.
  753%phrase_from_eof(Grammar, _):- compound(Grammar),!,arg(1,Grammar,TV),unify_next_or_eof(TV),!.
  754phrase_from_eof(Grammar, _):- term_variables(Grammar,[TV|_]),unify_next_or_eof(TV),!.
  755phrase_from_eof(Grammar, In):- throw(end_of_stream_signal(Grammar,In)).
  756
  757unify_next_or_eof(O) :- clause(t_l:'$last_comment'(I),_,Ref),!,I=O,erase(Ref).
  758unify_next_or_eof(end_of_file).

 parse_meta_ascii(Pred, +Codes, -Expr) is det

Parse Expression Codes.

  765parse_meta_ascii(Pred, S, Expr) :- is_stream(S),!,parse_meta_stream(Pred, S,Expr).
  766%parse_meta_ascii(Pred, S, Expr) :- open_string(S,SIS),!,parse_meta_stream(Pred, SIS,Expr).
  767parse_meta_ascii(Pred, Text, Expr):-
  768  quietly_pfs(txt_to_codes(Text,Codes)),
  769  =(ascii_,In),
  770  append_buffer_codes(In,[10]),
  771  append_buffer_codes(In,Codes),!,
  772  phrase_from_buffer_codes_nd(file_meta_with_comments(Pred,Expr), In).
  773
  774phrase_from_buffer_codes_nd(Grammar, In) :- peek_pending_codes(In,Pend),is_eof_codes(Pend),!,phrase_from_eof(Grammar,In).
  775phrase_from_buffer_codes_nd(Grammar, In) :-
  776  repeat,
  777  (phrase_from_buffer_codes(Grammar, In) *->
  778    ((peek_pending_codes(In,Pend),is_eof_codes(Pend))->!;true);(!,fail)).
  779
  780%phrase_from_buffer_codes(_Grammar, _In) :- peek_pending_codes(In,Pend),is_eof_codes(Pend),!,fail.
  781phrase_from_buffer_codes(Grammar, In):-
  782   quietly_pfs((remove_pending_buffer_codes(In,NewCodes), NewCodes \== [])),!,
  783   (must_or_rtrace(phrase(Grammar, NewCodes, More))->append_buffer_codes(In,More);(append_buffer_codes(In,NewCodes),!,fail)).
  784
  785
  786skipping_buffer_codes(Goal):-
  787 setup_call_cleanup(
  788   quietly_pfs((remove_pending_buffer_codes(In,OldCodes), clear_pending_buffer_codes)),
  789     Goal,
  790     quietly_pfs((clear_pending_buffer_codes,append_buffer_codes(In,OldCodes)))).
  791
  792is_eof_codes(Codes):- var(Codes),!,fail.
  793is_eof_codes(Codes):- Codes == [],!.
  794is_eof_codes(Codes):- Codes = [Code],!,is_eof_codes(Code).
  795is_eof_codes(end_of_file).
  796is_eof_codes(-1).
  797
  798file_eof(I,O):- notrace(file_eof0(I,O)).
  799file_eof0(I,O):- I==end_of_file,!,O=[].
  800file_eof0 --> [X],{ attvar(X), X = -1},!.
  801file_eof0 --> [X],{ attvar(X), X = end_of_file},!.
  802file_eof0 --> [X],{ var(X), X = -1},!.
  803file_eof0 --> [X],{ X = -1},!.
  804
  805expr_with_text(Out,DCG,O,S,E):-
  806   zalwayz(lazy_list_character_count(StartPos,S,M)),%integer(StartPos),
  807   call(DCG,M,ME),
  808   lazy_list_character_count(EndPos,ME,E),!,
  809   expr_with_text2(Out,DCG,O,StartPos,M,ME,EndPos,S,E).
  810
  811expr_with_text2(Out,_ ,O,StartPos,M,ME,EndPos,_,_):-
  812   integer(StartPos),integer(EndPos),!,
  813   bx(Len is EndPos - StartPos),length(Grabber,Len),!,
  814   get_some_with_comments(O,Grabber,Out,M,ME),!.
  815expr_with_text2(Out,_ ,O,end_of_file-StartPos,M,ME,end_of_file-EndPos,_,_):-
  816   integer(StartPos),integer(EndPos),!,
  817   bx(Len is StartPos - EndPos),length(Grabber,Len),!,
  818   get_some_with_comments(O,Grabber,Out,M,ME),!.
  819
  820expr_with_text2(Out,DCG,O,StartPos,M,ME,EndPos,S,E):-
  821   writeq(expr_with_text2(Out,DCG,O,StartPos,EndPos,S,E)),nl,
  822   get_some_with_comments(O,_Grabber,Out,M,ME),!.
  823
  824
  825%expr_with_text(Out,DCG,O,S,E):-
  826%   call(DCG,S,E) -> append(S,Some,E) -> get_some_with_comments(O,Some,Out,S,E),!.
  827get_some_with_comments(O,_,O,_,_):- compound(O),compound_name_arity(O,'$COMMENT',_),!.
  828get_some_with_comments(O,Txt,with_text(O,Str),S,_E):-append(Txt,_,S),!,text_to_string(Txt,Str).
  829
  830
  831dcg_peek_meta(Grammar,List,List):- (var(Grammar)->((N=2;N=1;between(3,20,N)),length(Grammar,N)); true),phrase(Grammar,List,_),!.
  832
  833
  834
  835
  836eoln --> [C],!, {nonvar(C),charvar(C),eoln(C)},!.
  837eoln(10).
  838eoln(13).
  839eoln --> \+ dcg_peek_meta([_]).
  840
  841:- meta_predicate(parse_meta_term(2,+,-)).  842
  843parse_meta_term(Pred, S, Expr) :- is_stream(S),!, parse_meta_stream(Pred, S,Expr).
  844parse_meta_term(Pred, string(String), Expr) :- !,parse_meta_ascii(Pred, String, Expr).
  845parse_meta_term(Pred, atom(String), Expr) :- !,parse_meta_ascii(Pred, String, Expr).
  846parse_meta_term(Pred, text(String), Expr) :- !,parse_meta_ascii(Pred, String, Expr).
  847parse_meta_term(Pred, (String), Expr) :- string(String),!,parse_meta_ascii(Pred, String, Expr).
  848parse_meta_term(Pred, [E|List], Expr) :- !, parse_meta_ascii(Pred, [E|List], Expr).
  849parse_meta_term(Pred, Other, Expr) :-
  850 quietly((l_open_input(Other,In)->Other\=@=In)),!,
  851   repeat, (at_end_of_stream(In)->(!,fail);true),
  852    parse_meta_term(Pred, In, Expr).
  853
  854
  855quoted_string(Text) --> (double_quoted_string(Text); single_quoted_string(Text)),!.
  856
  857double_quoted_string(Text)           --> `"`, !, zalwayz(s_string_cont(`"`,Text)),!.
  858single_quoted_string(Text)           --> `'`, !, zalwayz(s_string_cont(`'`,Text)),!.
  859single_quoted_string(Text)           --> ````, !, zalwayz(s_string_cont((````;`'`),Text)),!.
  860
  861s_string_cont(End,"")        --> End,!.
  862s_string_cont(End,Txt)       --> read_string_until(S,End), {text_to_string_safe(S,Txt)}.
  863
  864dcg_used_chars(DCG1, O, S, E):- phrase(DCG1,S, E),!,O=S.
  865
  866:- fixup_exports.