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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:- autoload(library(apply),[maplist/3]).   85:- autoload(library(date),[date_time_value/3]).   86:- autoload(library(shell),[shell/0]).   87
   88
   89/** <module> Quintus compatibility
   90
   91This  module  defines  several  predicates    from  the  Quintus  Prolog
   92libraries. Note that our library structure is totally different. If this
   93library were complete, Prolog  code  could   be  ported  by removing the
   94use_module/1 declarations, relying on the SWI-Prolog autoloader.
   95
   96Bluffers guide to porting:
   97
   98        * Remove =|use_module(library(...))|=
   99        * Run =|?- list_undefined.|=
  100        * Fix problems
  101
  102Of course, this library is incomplete ...
  103*/
  104
  105                /********************************
  106                *      SYSTEM INTERACTION       *
  107                *********************************/
  108
  109%!  unix(+Action)
  110%
  111%   This predicate provides a  partial   emulation  of the corresponding
  112%   Quintus predicate. It  provides  access   to  some  operating system
  113%   features and unlike the  name  suggests,   is  not  operating system
  114%   specific. Defined actions are below.
  115%
  116%     - system(+Command)
  117%       Equivalent to shell(Command)
  118%     - shell(+Command)
  119%       Equivalent to shell(Command)
  120%     - access(File, 0)
  121%       Equivalent to access_file(File, read)
  122%     - cd(Dir)
  123%       Equivalent to working_directory(_, Dir)
  124%     - args(List)
  125%       Equivalent to current_prolog_flag(os_argv, List).
  126%     - argv(List)
  127%       Equivalent to args(List), but arguments that are syntactically
  128%       valid numbers are passed as a number.
  129
  130unix(system(Command)) :-
  131    shell(Command).
  132unix(shell(Command)) :-
  133    shell(Command).
  134unix(shell) :-
  135    shell.
  136unix(access(File, 0)) :-
  137    access_file(File, read).
  138unix(cd) :-
  139    expand_file_name(~, [Home]),
  140    working_directory(_, Home).
  141unix(cd(Dir)) :-
  142    working_directory(_, Dir).
  143unix(args(L)) :-
  144    current_prolog_flag(os_argv, L).
  145unix(argv(L)) :-
  146    current_prolog_flag(os_argv, S),
  147    maplist(to_prolog, S, L).
  148
  149to_prolog(S, A) :-
  150    name(S, L),
  151    name(A, L).
  152
  153
  154                /********************************
  155                *        META PREDICATES        *
  156                *********************************/
  157
  158%!  otherwise
  159%
  160%   For (A -> B ; otherwise -> C)
  161
  162otherwise.
  163
  164
  165                /********************************
  166                *          ARITHMETIC           *
  167                *********************************/
  168
  169%!  abs(+Number, -Absolute)
  170%   Unify `Absolute' with the absolute value of `Number'.
  171
  172abs(Number, Absolute) :-
  173    Absolute is abs(Number).
  174
  175%!  sin(+Angle, -Sine) is det.
  176%!  cos(+Angle, -Cosine) is det.
  177%!  tan(+Angle, -Tangent) is det.
  178%!  log(+X, -NatLog) is det.
  179%!  log10(+X, -Log) is det.
  180%!  pow(+X, +Y, -Pow) is det.
  181%!  ceiling(+X, -Value) is det.
  182%!  floor(+X, -Value) is det.
  183%!  round(+X, -Value) is det.
  184%!  sqrt(+X, -Value) is det.
  185%!  acos(+X, -Value) is det.
  186%!  asin(+X, -Value) is det.
  187%!  atan(+X, -Value) is det.
  188%!  atan2(+Y, +X, -Value) is det.
  189%!  sign(+X, -Value) is det.
  190%
  191%   Math library predicates. SWI-Prolog (and   ISO) support these as
  192%   functions under is/2, etc.
  193%
  194%   @compat Quintus Prolog.
  195%   @deprecated Do not use these predicates except for compatibility
  196%   reasons.
  197
  198sin(A, V) :-      V is sin(A).
  199cos(A, V) :-      V is cos(A).
  200tan(A, V) :-      V is tan(A).
  201log(A, V) :-      V is log(A).
  202log10(X, V) :-    V is log10(X).
  203pow(X,Y,V) :-     V is X**Y.
  204ceiling(X, V) :-  V is ceil(X).
  205floor(X, V) :-    V is floor(X).
  206round(X, V) :-    V is round(X).
  207sqrt(X, V) :-     V is sqrt(X).
  208acos(X, V) :-     V is acos(X).
  209asin(X, V) :-     V is asin(X).
  210atan(X, V) :-     V is atan(X).
  211atan2(Y, X, V) :- V is atan(Y, X).
  212sign(X, V) :-     V is sign(X).
  213
  214
  215                 /*******************************
  216                 *      TERM MANIPULATION       *
  217                 *******************************/
  218
  219%!  genarg(?Index, +Term, ?Arg) is nondet.
  220%
  221%   Generalised version of ISO arg/3.  SWI-Prolog's arg/3 is already
  222%   genarg/3.
  223
  224genarg(N, T, A) :-
  225    arg(N, T, A).
  226
  227
  228                 /*******************************
  229                 *            FLAGS             *
  230                 *******************************/
  231
  232%!  prolog_flag(?Flag, ?Value) is nondet.
  233%
  234%   Same as ISO current_prolog_flag/2.  Maps =version=.
  235%
  236%   @bug    Should map relevant Quintus flag identifiers.
  237
  238prolog_flag(version, Version) :-
  239    !,
  240    current_prolog_flag(version_data, swi(Major, Minor, Patch, _)),
  241    current_prolog_flag(arch, Arch),
  242    current_prolog_flag(compiled_at, Compiled),
  243    atomic_list_concat(['SWI-Prolog ',
  244                 Major, '.', Minor, '.', Patch,
  245                 ' (', Arch, '): ', Compiled], Version).
  246prolog_flag(Flag, Value) :-
  247    current_prolog_flag(Flag, Value).
  248
  249
  250                 /*******************************
  251                 *          STATISTICS          *
  252                 *******************************/
  253
  254%       Here used to be a definition of Quintus statistics/2 in traditional
  255%       SWI-Prolog statistics/2.  The current built-in emulates Quintus
  256%       almost completely.
  257
  258
  259                 /*******************************
  260                 *           DATE/TIME          *
  261                 *******************************/
  262
  263%!  date(-Date) is det.
  264%
  265%   Get current date as date(Y,M,D)
  266
  267date(Date) :-
  268    get_time(T),
  269    stamp_date_time(T, DaTime, local),
  270    date_time_value(date, DaTime, Date).
  271
  272
  273                /********************************
  274                *          STYLE CHECK          *
  275                *********************************/
  276
  277%!  no_style_check(Style) is det.
  278%
  279%   Same as SWI-Prolog =|style_check(-Style)|=.   The Quintus option
  280%   =single_var= is mapped to =singleton=.
  281%
  282%   @see style_check/1.
  283
  284q_style_option(single_var, singleton) :- !.
  285q_style_option(Option, Option).
  286
  287no_style_check(QOption) :-
  288    q_style_option(QOption, SWIOption),
  289    style_check(-SWIOption).
  290
  291
  292                /********************************
  293                *         DIRECTIVES            *
  294                *********************************/
  295
  296%!  mode(+ModeDecl) is det.
  297%
  298%   Ignore a DEC10/Quintus `:-   mode(Head)`  declaration. Typically
  299%   these declarations are written in   operator  form. The operator
  300%   declaration is not part of the   Quintus  emulation library. The
  301%   following declaration is compatible with Quintus:
  302%
  303%     ==
  304%     :- op(1150, fx, [(mode)]).
  305%     ==
  306
  307mode(_).
  308
  309
  310                 /*******************************
  311                 *            TYPES             *
  312                 *******************************/
  313
  314%!  simple(@Term) is semidet.
  315%
  316%   Term is atomic or a variable.
  317
  318simple(X) :-
  319    (   atomic(X)
  320    ->  true
  321    ;   var(X)
  322    ).
  323
  324
  325                 /*******************************
  326                 *            STREAMS           *
  327                 *******************************/
  328
  329%!  current_stream(?Object, ?Mode, ?Stream)
  330%
  331%   SICStus/Quintus and backward compatible predicate.  New code should
  332%   be using the ISO compatible stream_property/2.
  333
  334current_stream(Object, Mode, Stream) :-
  335    stream_property(Stream, mode(FullMode)),
  336    stream_mode(FullMode, Mode),
  337    (   stream_property(Stream, file_name(Object0))
  338    ->  true
  339    ;   stream_property(Stream, file_no(Object0))
  340    ->  true
  341    ;   Object0 = []
  342    ),
  343    Object = Object0.
  344
  345stream_mode(read,   read).
  346stream_mode(write,  write).
  347stream_mode(append, write).
  348stream_mode(update, write).
  349
  350%!  stream_position(+Stream, -Old, +New)
  351%
  352%   True when Old is the current position   in Stream and the stream
  353%   has been repositioned to New.
  354%
  355%   @deprecated New code should use the ISO predicates
  356%   stream_property/2 and set_stream_position/2.
  357
  358stream_position(Stream, Old, New) :-
  359    stream_property(Stream, position(Old)),
  360    set_stream_position(Stream, New).
  361
  362
  363%!  skip_line is det.
  364%!  skip_line(Stream) is det.
  365%
  366%   Skip  the  rest  of  the  current  line  (on  Stream).  Same  as
  367%   =|skip(0'\n)|=.
  368
  369skip_line :-
  370    skip(10).
  371skip_line(Stream) :-
  372    skip(Stream, 10).
  373
  374
  375                 /*******************************
  376                 *         COMPILATION          *
  377                 *******************************/
  378
  379%!  compile(+Files) is det.
  380%
  381%   Compile   files.   SWI-Prolog   doesn't    distinguish   between
  382%   compilation and consult.
  383%
  384%   @see load_files/2.
  385
  386:- meta_predicate
  387    compile(:).  388
  389compile(Files) :-
  390    consult(Files).
  391
  392                 /*******************************
  393                 *         ATOM-HANDLING        *
  394                 *******************************/
  395
  396%!  atom_char(+Char, -Code) is det.
  397%!  atom_char(-Char, +Code) is det.
  398%
  399%   Same as ISO char_code/2.
  400
  401atom_char(Char, Code) :-
  402    char_code(Char, Code).
  403
  404%!  midstring(?ABC, ?B, ?AC) is nondet.
  405%!  midstring(?ABC, ?B, ?AC, LenA) is nondet.
  406%!  midstring(?ABC, ?B, ?AC, LenA, LenB) is nondet.
  407%!  midstring(?ABC, ?B, ?AC, LenA, LenB, LenC) is nondet.
  408%
  409%   Too difficult to explain.  See the Quintus docs.  As far as I
  410%   understand them the code below emulates this function just fine.
  411
  412midstring(ABC, B, AC) :-
  413    midstring(ABC, B, AC, _, _, _).
  414midstring(ABC, B, AC, LenA) :-
  415    midstring(ABC, B, AC, LenA, _, _).
  416midstring(ABC, B, AC, LenA, LenB) :-
  417    midstring(ABC, B, AC, LenA, LenB, _).
  418midstring(ABC, B, AC, LenA, LenB, LenC) :-      % -ABC, +B, +AC
  419    var(ABC),
  420    !,
  421    atom_length(AC, LenAC),
  422    (   nonvar(LenA) ; nonvar(LenC)
  423    ->  plus(LenA, LenC, LenAC)
  424    ;   true
  425    ),
  426    sub_atom(AC, 0, LenA, _, A),
  427    LenC is LenAC - LenA,
  428    sub_atom(AC, _, LenC, 0, C),
  429    atom_length(B, LenB),
  430    atomic_list_concat([A,B,C], ABC).
  431midstring(ABC, B, AC, LenA, LenB, LenC) :-
  432    sub_atom(ABC, LenA, LenB, LenC, B),
  433    sub_atom(ABC, 0, LenA, _, A),
  434    sub_atom(ABC, _, LenC, 0, C),
  435    atom_concat(A, C, AC).
  436
  437
  438                 /*******************************
  439                 *           EXCEPTIONS         *
  440                 *******************************/
  441
  442%!  raise_exception(+Term)
  443%
  444%   Quintus compatible exception handling
  445
  446raise_exception(Term) :-
  447    throw(Term).
  448
  449%!  on_exception(+Template, :Goal, :Recover)
  450
  451:- meta_predicate
  452    on_exception(+, 0, 0).  453
  454on_exception(Except, Goal, Recover) :-
  455    catch(Goal, Except, Recover)