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    1/*  Part of SWI-Prolog
    2
    3    Author:        Jan Wielemaker
    4    E-mail:        J.Wielemaker@vu.nl
    5    WWW:           http://www.swi-prolog.org
    6    Copyright (c)  1985-2015, University of Amsterdam
    7                              VU University Amsterdam
    8    All rights reserved.
    9
   10    Redistribution and use in source and binary forms, with or without
   11    modification, are permitted provided that the following conditions
   12    are met:
   13
   14    1. Redistributions of source code must retain the above copyright
   15       notice, this list of conditions and the following disclaimer.
   16
   17    2. Redistributions in binary form must reproduce the above copyright
   18       notice, this list of conditions and the following disclaimer in
   19       the documentation and/or other materials provided with the
   20       distribution.
   21
   22    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   23    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   24    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   25    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   26    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   27    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   28    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   29    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   30    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   31    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   32    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   33    POSSIBILITY OF SUCH DAMAGE.
   34*/
   35
   36:- module(quintus,
   37        [ unix/1,
   38%         file_exists/1,
   39
   40          abs/2,
   41          sin/2,
   42          cos/2,
   43          tan/2,
   44          log/2,
   45          log10/2,
   46          pow/3,
   47          ceiling/2,
   48          floor/2,
   49          round/2,
   50          acos/2,
   51          asin/2,
   52          atan/2,
   53          atan2/3,
   54          sign/2,
   55          sqrt/2,
   56
   57          genarg/3,
   58
   59          (mode)/1,
   60          no_style_check/1,
   61          otherwise/0,
   62          simple/1,
   63%         statistics/2,                 % Please access as quintus:statistics/2
   64          prolog_flag/2,
   65
   66          date/1,                       % -date(Year, Month, Day)
   67
   68          current_stream/3,             % ?File, ?Mode, ?Stream
   69          stream_position/3,            % +Stream, -Old, +New
   70          skip_line/0,
   71          skip_line/1,                  % +Stream
   72
   73          compile/1,                    % +File(s)
   74
   75          atom_char/2,
   76          midstring/3,                  % ABC, B, AC
   77          midstring/4,                  % ABC, B, AC, LenA
   78          midstring/5,                  % ABC, B, AC, LenA, LenB
   79          midstring/6,                  % ABC, B, AC, LenA, LenB, LenC
   80
   81          raise_exception/1,            % +Exception
   82          on_exception/3                % +Ball, :Goal, :Recover
   83        ]).   84:- use_module(library(lists), [member/2]).   85
   86/** <module> Quintus compatibility
   87
   88This  module  defines  several  predicates    from  the  Quintus  Prolog
   89libraries. Note that our library structure is totally different. If this
   90library were complete, Prolog  code  could   be  ported  by removing the
   91use_module/1 declarations, relying on the SWI-Prolog autoloader.
   92
   93Bluffers guide to porting:
   94
   95        * Remove =|use_module(library(...))|=
   96        * Run =|?- list_undefined.|=
   97        * Fix problems
   98
   99Of course, this library is incomplete ...
  100*/
  101
  102                /********************************
  103                *      SYSTEM INTERACTION       *
  104                *********************************/
  105
  106%!  unix(+Action)
  107%   interface to  Unix.
  108
  109unix(system(Command)) :-
  110    shell(Command).
  111unix(shell(Command)) :-
  112    shell(Command).
  113unix(shell) :-
  114    shell.
  115unix(access(File, 0)) :-
  116    access_file(File, read).
  117unix(cd) :-
  118    expand_file_name(~, [Home]),
  119    working_directory(_, Home).
  120unix(cd(Dir)) :-
  121    working_directory(_, Dir).
  122unix(args(L)) :-
  123    current_prolog_flag(os_argv, L).
  124unix(argv(L)) :-
  125    current_prolog_flag(os_argv, S),
  126    maplist(to_prolog, S, L).
  127
  128to_prolog(S, A) :-
  129    name(S, L),
  130    name(A, L).
  131
  132
  133                /********************************
  134                *        META PREDICATES        *
  135                *********************************/
  136
  137%!  otherwise
  138%
  139%   For (A -> B ; otherwise -> C)
  140
  141otherwise.
  142
  143
  144                /********************************
  145                *          ARITHMETIC           *
  146                *********************************/
  147
  148%!  abs(+Number, -Absolute)
  149%   Unify `Absolute' with the absolute value of `Number'.
  150
  151abs(Number, Absolute) :-
  152    Absolute is abs(Number).
  153
  154%!  sin(+Angle, -Sine) is det.
  155%!  cos(+Angle, -Cosine) is det.
  156%!  tan(+Angle, -Tangent) is det.
  157%!  log(+X, -NatLog) is det.
  158%!  log10(+X, -Log) is det.
  159%
  160%   Math library predicates. SWI-Prolog (and   ISO) support these as
  161%   functions under is/2, etc.
  162
  163sin(A, V) :-      V is sin(A).
  164cos(A, V) :-      V is cos(A).
  165tan(A, V) :-      V is tan(A).
  166log(A, V) :-      V is log(A).
  167log10(X, V) :-    V is log10(X).
  168pow(X,Y,V) :-     V is X**Y.
  169ceiling(X, V) :-  V is ceil(X).
  170floor(X, V) :-    V is floor(X).
  171round(X, V) :-    V is round(X).
  172sqrt(X, V) :-     V is sqrt(X).
  173acos(X, V) :-     V is acos(X).
  174asin(X, V) :-     V is asin(X).
  175atan(X, V) :-     V is atan(X).
  176atan2(Y, X, V) :- V is atan(Y, X).
  177sign(X, V) :-     V is sign(X).
  178
  179
  180                 /*******************************
  181                 *      TERM MANIPULATION       *
  182                 *******************************/
  183
  184%!  genarg(?Index, +Term, ?Arg) is nondet.
  185%
  186%   Generalised version of ISO arg/3.  SWI-Prolog's arg/3 is already
  187%   genarg/3.
  188
  189genarg(N, T, A) :-
  190    arg(N, T, A).
  191
  192
  193                 /*******************************
  194                 *            FLAGS             *
  195                 *******************************/
  196
  197%!  prolog_flag(?Flag, ?Value) is nondet.
  198%
  199%   Same as ISO current_prolog_flag/2.  Maps =version=.
  200%
  201%   @bug    Should map relevant Quintus flag identifiers.
  202
  203prolog_flag(version, Version) :-
  204    !,
  205    current_prolog_flag(version_data, swi(Major, Minor, Patch, _)),
  206    current_prolog_flag(arch, Arch),
  207    current_prolog_flag(compiled_at, Compiled),
  208    atomic_list_concat(['SWI-Prolog ',
  209                 Major, '.', Minor, '.', Patch,
  210                 ' (', Arch, '): ', Compiled], Version).
  211prolog_flag(Flag, Value) :-
  212    current_prolog_flag(Flag, Value).
  213
  214
  215                 /*******************************
  216                 *          STATISTICS          *
  217                 *******************************/
  218
  219%       Here used to be a definition of Quintus statistics/2 in traditional
  220%       SWI-Prolog statistics/2.  The current built-in emulates Quintus
  221%       almost completely.
  222
  223
  224                 /*******************************
  225                 *           DATE/TIME          *
  226                 *******************************/
  227
  228%!  date(-Date) is det.
  229%
  230%   Get current date as date(Y,M,D)
  231
  232date(Date) :-
  233    get_time(T),
  234    stamp_date_time(T, DaTime, local),
  235    date_time_value(date, DaTime, Date).
  236
  237
  238                /********************************
  239                *          STYLE CHECK          *
  240                *********************************/
  241
  242%!  no_style_check(Style) is det.
  243%
  244%   Same as SWI-Prolog =|style_check(-Style)|=.   The Quintus option
  245%   =single_var= is mapped to =singleton=.
  246%
  247%   @see style_check/1.
  248
  249q_style_option(single_var, singleton) :- !.
  250q_style_option(Option, Option).
  251
  252no_style_check(QOption) :-
  253    q_style_option(QOption, SWIOption),
  254    style_check(-SWIOption).
  255
  256
  257                /********************************
  258                *         DIRECTIVES            *
  259                *********************************/
  260
  261%!  mode(+ModeDecl) is det.
  262%
  263%   Ignore a DEC10/Quintus `:-   mode(Head)`  declaration. Typically
  264%   these declarations are written in   operator  form. The operator
  265%   declaration is not part of the   Quintus  emulation library. The
  266%   following declaration is compatible with Quintus:
  267%
  268%     ==
  269%     :- op(1150, fx, [(mode)]).
  270%     ==
  271
  272mode(_).
  273
  274
  275                 /*******************************
  276                 *            TYPES             *
  277                 *******************************/
  278
  279%!  simple(@Term) is semidet.
  280%
  281%   Term is atomic or a variable.
  282
  283simple(X) :-
  284    (   atomic(X)
  285    ->  true
  286    ;   var(X)
  287    ).
  288
  289
  290                 /*******************************
  291                 *            STREAMS           *
  292                 *******************************/
  293
  294%!  current_stream(?Object, ?Mode, ?Stream)
  295%
  296%   SICStus/Quintus and backward compatible predicate.  New code should
  297%   be using the ISO compatible stream_property/2.
  298
  299current_stream(Object, Mode, Stream) :-
  300    stream_property(Stream, mode(FullMode)),
  301    stream_mode(FullMode, Mode),
  302    (   stream_property(Stream, file_name(Object0))
  303    ->  true
  304    ;   stream_property(Stream, file_no(Object0))
  305    ->  true
  306    ;   Object0 = []
  307    ),
  308    Object = Object0.
  309
  310stream_mode(read,   read).
  311stream_mode(write,  write).
  312stream_mode(append, write).
  313stream_mode(update, write).
  314
  315%!  stream_position(+Stream, -Old, +New)
  316%
  317%   True when Old is the current position   in Stream and the stream
  318%   has been repositioned to New.
  319%
  320%   @deprecated New code should use the ISO predicates
  321%   stream_property/2 and set_stream_position/2.
  322
  323stream_position(Stream, Old, New) :-
  324    stream_property(Stream, position(Old)),
  325    set_stream_position(Stream, New).
  326
  327
  328%!  skip_line is det.
  329%!  skip_line(Stream) is det.
  330%
  331%   Skip  the  rest  of  the  current  line  (on  Stream).  Same  as
  332%   =|skip(0'\n)|=.
  333
  334skip_line :-
  335    skip(10).
  336skip_line(Stream) :-
  337    skip(Stream, 10).
  338
  339
  340                 /*******************************
  341                 *         COMPILATION          *
  342                 *******************************/
  343
  344%!  compile(+Files) is det.
  345%
  346%   Compile   files.   SWI-Prolog   doesn't    distinguish   between
  347%   compilation and consult.
  348%
  349%   @see load_files/2.
  350
  351:- meta_predicate
  352    compile(:).  353
  354compile(Files) :-
  355    consult(Files).
  356
  357                 /*******************************
  358                 *         ATOM-HANDLING        *
  359                 *******************************/
  360
  361%!  atom_char(+Char, -Code) is det.
  362%!  atom_char(-Char, +Code) is det.
  363%
  364%   Same as ISO char_code/2.
  365
  366atom_char(Char, Code) :-
  367    char_code(Char, Code).
  368
  369%!  midstring(?ABC, ?B, ?AC) is nondet.
  370%!  midstring(?ABC, ?B, ?AC, LenA) is nondet.
  371%!  midstring(?ABC, ?B, ?AC, LenA, LenB) is nondet.
  372%!  midstring(?ABC, ?B, ?AC, LenA, LenB, LenC) is nondet.
  373%
  374%   Too difficult to explain.  See the Quintus docs.  As far as I
  375%   understand them the code below emulates this function just fine.
  376
  377midstring(ABC, B, AC) :-
  378    midstring(ABC, B, AC, _, _, _).
  379midstring(ABC, B, AC, LenA) :-
  380    midstring(ABC, B, AC, LenA, _, _).
  381midstring(ABC, B, AC, LenA, LenB) :-
  382    midstring(ABC, B, AC, LenA, LenB, _).
  383midstring(ABC, B, AC, LenA, LenB, LenC) :-      % -ABC, +B, +AC
  384    var(ABC),
  385    !,
  386    atom_length(AC, LenAC),
  387    (   nonvar(LenA) ; nonvar(LenC)
  388    ->  plus(LenA, LenC, LenAC)
  389    ;   true
  390    ),
  391    sub_atom(AC, 0, LenA, _, A),
  392    LenC is LenAC - LenA,
  393    sub_atom(AC, _, LenC, 0, C),
  394    atom_length(B, LenB),
  395    atomic_list_concat([A,B,C], ABC).
  396midstring(ABC, B, AC, LenA, LenB, LenC) :-
  397    sub_atom(ABC, LenA, LenB, LenC, B),
  398    sub_atom(ABC, 0, LenA, _, A),
  399    sub_atom(ABC, _, LenC, 0, C),
  400    atom_concat(A, C, AC).
  401
  402
  403                 /*******************************
  404                 *           EXCEPTIONS         *
  405                 *******************************/
  406
  407%!  raise_exception(+Term)
  408%
  409%   Quintus compatible exception handling
  410
  411raise_exception(Term) :-
  412    throw(Term).
  413
  414%!  on_exception(+Template, :Goal, :Recover)
  415
  416:- meta_predicate
  417    on_exception(+, 0, 0).  418
  419on_exception(Except, Goal, Recover) :-
  420    catch(Goal, Except, Recover)