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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)  2007-2015, 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(pldoc_latex,
   37          [ doc_latex/3,                % +Items, +OutFile, +Options
   38            latex_for_file/3,           % +FileSpec, +Out, +Options
   39            latex_for_wiki_file/3,      % +FileSpec, +Out, +Options
   40            latex_for_predicates/3      % +PI, +Out, +Options
   41          ]).   42:- use_module(library(pldoc)).   43:- use_module(library(readutil)).   44:- use_module(library(error)).   45:- use_module(library(apply)).   46:- use_module(library(option)).   47:- use_module(library(lists)).   48:- use_module(library(debug)).   49:- use_module(pldoc(doc_wiki)).   50:- use_module(pldoc(doc_process)).   51:- use_module(pldoc(doc_modes)).   52:- use_module(library(pairs), [pairs_values/2]).   53:- use_module(library(prolog_source), [file_name_on_path/2]).   54:- use_module(library(prolog_xref), [xref_hook/1]).   55:- use_module(pldoc(doc_html),          % we cannot import all as the
   56              [ doc_file_objects/5,     % \commands have the same name
   57                unquote_filespec/2,
   58                doc_tag_title/2,
   59                existing_linked_file/2,
   60                pred_anchor_name/3,
   61                private/2,
   62                (multifile)/2,
   63                is_pi/1,
   64                is_op_type/2
   65              ]).   66
   67/** <module> PlDoc LaTeX backend
   68
   69This  module  translates  the  Herbrand   term  from  the  documentation
   70extracting module doc_wiki.pl into a  LaTeX   document  for  us with the
   71pl.sty LaTeX style file. The function of  this module is very similar to
   72doc_html.pl, providing the HTML backend,  and the implementation follows
   73the same paradigm. The module can
   74
   75        * Generate LaTeX documentation for a Prolog file, both for
   76        printing and embedding in a larger document using
   77        latex_for_file/3.
   78
   79        * Generate LaTeX from a Wiki file using latex_for_wiki_file/3
   80
   81        * Generate LaTeX for a single predicate or a list of predicates
   82        for embedding in a document using latex_for_predicates/3.
   83
   84@tbd See TODO
   85@author Jan Wielemaker
   86*/
   87
   88:- predicate_options(doc_latex/3, 3,
   89                     [ stand_alone(boolean),
   90                       public_only(boolean),
   91                       section_level(oneof([section,subsection,subsubsection])),
   92                       summary(atom)
   93                     ]).   94:- predicate_options(latex_for_file/3, 3,
   95                     [ stand_alone(boolean),
   96                       public_only(boolean),
   97                       section_level(oneof([section,subsection,subsubsection]))
   98                     ]).   99:- predicate_options(latex_for_predicates/3, 3,
  100                     [                          % no options
  101                     ]).  102:- predicate_options(latex_for_wiki_file/3, 3,
  103                     [ stand_alone(boolean),
  104                       public_only(boolean),
  105                       section_level(oneof([section,subsection,subsubsection]))
  106                     ]).  107
  108
  109:- thread_local
  110    options/1,
  111    documented/1.  112
  113current_options(Options) :-
  114    options(Current),
  115    !,
  116    Options = Current.
  117current_options([]).
  118
  119%!  doc_latex(+Spec, +OutFile, +Options) is det.
  120%
  121%   Process one or  more  objects,  writing   the  LaTeX  output  to
  122%   OutFile.  Spec is one of:
  123%
  124%     - Name/Arity
  125%       Generate documentation for predicate
  126%     - Name//Arity
  127%       Generate documentation for DCG rule
  128%     - File
  129%       If File is a prolog file (as defined by
  130%       user:prolog_file_type/2), process using
  131%       latex_for_file/3, otherwise process using
  132%       latex_for_wiki_file/3.
  133%
  134%   Typically Spec is either a  list  of   filenames  or  a  list of
  135%   predicate indicators.   Defined options are:
  136%
  137%     - stand_alone(+Bool)
  138%       If =true= (default), create a document that can be run
  139%       through LaTeX.  If =false=, produce a document to be
  140%       included in another LaTeX document.
  141%     - public_only(+Bool)
  142%       If =true= (default), only emit documentation for
  143%       exported predicates.
  144%     - section_level(+Level)
  145%       Outermost section level produced. Level is the
  146%       name of a LaTeX section command.  Default is =section=.
  147%     - summary(+File)
  148%       Write summary declarations to the named File.
  149%     - modules(+List)
  150%       If [[Name/Arity]] needs to be resolved, search for the
  151%       predicates in the given modules.
  152%     - module(+Module)
  153%       Same as modules([Module]).
  154
  155doc_latex(Spec, OutFile, Options) :-
  156    load_urldefs,
  157    merge_options(Options,
  158                  [ include_reexported(true)
  159                  ],
  160                  Options1),
  161    retractall(documented(_)),
  162    setup_call_cleanup(
  163        asserta(options(Options), Ref),
  164        phrase(process_items(Spec, [body], Options1), Tokens),
  165        erase(Ref)),
  166    setup_call_cleanup(
  167        open(OutFile, write, Out),
  168        print_latex(Out, Tokens, Options1),
  169        close(Out)),
  170    latex_summary(Options).
  171
  172process_items([], Mode, _) -->
  173    !,
  174    pop_mode(body, Mode, _).
  175process_items([H|T], Mode, Options) -->
  176    process_items(H, Mode, Mode1, Options),
  177    process_items(T, Mode1, Options).
  178process_items(Spec, Mode, Options) -->
  179    {Mode = [Mode0|_]},
  180    process_items(Spec, Mode, Mode1, Options),
  181    pop_mode(Mode0, Mode1, _).
  182
  183process_items(PI, Mode0, Mode, Options) -->
  184    { is_pi(PI) },
  185    !,
  186    need_mode(description, Mode0, Mode),
  187    latex_tokens_for_predicates(PI, Options).
  188process_items(FileSpec, Mode0, Mode, Options) -->
  189    {   (   absolute_file_name(FileSpec,
  190                               [ file_type(prolog),
  191                                 access(read),
  192                                 file_errors(fail)
  193                               ],
  194                               File)
  195        ->  true
  196        ;   absolute_file_name(FileSpec,
  197                               [ access(read)
  198                               ],
  199                               File)
  200        ),
  201        file_name_extension(_Base, Ext, File)
  202    },
  203    need_mode(body, Mode0, Mode),
  204    (   { user:prolog_file_type(Ext, prolog) }
  205    ->  latex_tokens_for_file(File, Options)
  206    ;   latex_tokens_for_wiki_file(File, Options)
  207    ).
  208
  209
  210%!  latex_for_file(+File, +Out, +Options) is det.
  211%
  212%   Generate a LaTeX description of all commented predicates in
  213%   File, writing the LaTeX text to the stream Out. Supports
  214%   the options =stand_alone=, =public_only= and =section_level=.
  215%   See doc_latex/3 for a description of the options.
  216
  217latex_for_file(FileSpec, Out, Options) :-
  218    load_urldefs,
  219    phrase(latex_tokens_for_file(FileSpec, Options), Tokens),
  220    print_latex(Out, Tokens, Options).
  221
  222
  223%!  latex_tokens_for_file(+FileSpec, +Options)//
  224
  225latex_tokens_for_file(FileSpec, Options, Tokens, Tail) :-
  226    absolute_file_name(FileSpec,
  227                       [ file_type(prolog),
  228                         access(read)
  229                       ],
  230                       File),
  231    doc_file_objects(FileSpec, File, Objects, FileOptions, Options),
  232    asserta(options(Options), Ref),
  233    call_cleanup(phrase(latex([ \file_header(File, FileOptions)
  234                              | \objects(Objects, FileOptions)
  235                              ]),
  236                        Tokens, Tail),
  237                 erase(Ref)).
  238
  239
  240%!  latex_for_wiki_file(+File, +Out, +Options) is det.
  241%
  242%   Write a LaTeX translation of  a  Wiki   file  to  the steam Out.
  243%   Supports   the   options   =stand_alone=,    =public_only=   and
  244%   =section_level=.  See  doc_latex/3  for  a  description  of  the
  245%   options.
  246
  247latex_for_wiki_file(FileSpec, Out, Options) :-
  248    load_urldefs,
  249    phrase(latex_tokens_for_wiki_file(FileSpec, Options), Tokens),
  250    print_latex(Out, Tokens, Options).
  251
  252latex_tokens_for_wiki_file(FileSpec, Options, Tokens, Tail) :-
  253    absolute_file_name(FileSpec, File,
  254                       [ access(read)
  255                       ]),
  256    read_file_to_codes(File, String, []),
  257    b_setval(pldoc_file, File),
  258    asserta(options(Options), Ref),
  259    call_cleanup((wiki_codes_to_dom(String, [], DOM),
  260                  phrase(latex(DOM), Tokens, Tail)
  261                 ),
  262                 (nb_delete(pldoc_file),
  263                  erase(Ref))).
  264
  265
  266%!  latex_for_predicates(+PI:list, +Out, +Options) is det.
  267%
  268%   Generate LaTeX for a list  of   predicate  indicators. This does
  269%   *not*   produce   the    \begin{description}...\end{description}
  270%   environment, just a plain list   of \predicate, etc. statements.
  271%   The current implementation ignores Options.
  272
  273latex_for_predicates(Spec, Out, Options) :-
  274    load_urldefs,
  275    phrase(latex_tokens_for_predicates(Spec, Options), Tokens),
  276    print_latex(Out, [nl_exact(0)|Tokens], Options).
  277
  278latex_tokens_for_predicates([], _Options) --> !.
  279latex_tokens_for_predicates([H|T], Options) -->
  280    !,
  281    latex_tokens_for_predicates(H, Options),
  282    latex_tokens_for_predicates(T, Options).
  283latex_tokens_for_predicates(PI, Options) -->
  284    { generic_pi(PI),
  285      !,
  286      (   doc_comment(PI, Pos, _Summary, Comment)
  287      ->  true
  288      ;   Comment = ''
  289      )
  290    },
  291    object(PI, Pos, Comment, [description], _, Options).
  292latex_tokens_for_predicates(Spec, Options) -->
  293    { findall(PI, documented_pi(Spec, PI, Options), List),
  294      (   List == []
  295      ->  print_message(warning, pldoc(no_predicates_from(Spec)))
  296      ;   true
  297      )
  298    },
  299    latex_tokens_for_predicates(List, Options).
  300
  301documented_pi(Spec, PI, Options) :-
  302    option(modules(List), Options),
  303    member(M, List),
  304    generalise_spec(Spec, PI, M),
  305    doc_comment(PI, _Pos, _Summary, _Comment),
  306    !.
  307documented_pi(Spec, PI, Options) :-
  308    option(module(M), Options),
  309    generalise_spec(Spec, PI, M),
  310    doc_comment(PI, _Pos, _Summary, _Comment),
  311    !.
  312documented_pi(Spec, PI, _Options) :-
  313    generalise_spec(Spec, PI, _),
  314    doc_comment(PI, _Pos, _Summary, _Comment).
  315
  316generic_pi(Module:Name/Arity) :-
  317    atom(Module), atom(Name), integer(Arity),
  318    !.
  319generic_pi(Module:Name//Arity) :-
  320    atom(Module), atom(Name), integer(Arity).
  321
  322generalise_spec(Name/Arity, M:Name/Arity, M).
  323generalise_spec(Name//Arity, M:Name//Arity, M).
  324
  325
  326                 /*******************************
  327                 *       LATEX PRODUCTION       *
  328                 *******************************/
  329
  330:- thread_local
  331    fragile/0.                      % provided when in fragile mode
  332
  333latex([]) -->
  334    !,
  335    [].
  336latex(Atomic) -->
  337    { string(Atomic),
  338      atom_string(Atom, Atomic),
  339      sub_atom(Atom, 0, _, 0, 'LaTeX')
  340    },
  341    !,
  342    [ latex('\\LaTeX{}') ].
  343latex(Atomic) -->                       % can this actually happen?
  344    { atomic(Atomic),
  345      !,
  346      atom_string(Atom, Atomic),
  347      findall(x, sub_atom(Atom, _, _, _, '\n'), Xs),
  348      length(Xs, Lines)
  349    },
  350    (   {Lines == 0}
  351    ->  [ Atomic ]
  352    ;   [ nl(Lines) ]
  353    ).
  354latex(List) -->
  355    latex_special(List, Rest),
  356    !,
  357    latex(Rest).
  358latex(w(Word)) -->
  359    [ Word ].
  360latex([H|T]) -->
  361    !,
  362    (   latex(H)
  363    ->  latex(T)
  364    ;   { print_message(error, latex(failed(H))) },
  365        latex(T)
  366    ).
  367
  368% high level commands
  369latex(h1(Attrs, Content)) -->
  370    latex_section(0, Attrs, Content).
  371latex(h2(Attrs, Content)) -->
  372    latex_section(1, Attrs, Content).
  373latex(h3(Attrs, Content)) -->
  374    latex_section(2, Attrs, Content).
  375latex(h4(Attrs, Content)) -->
  376    latex_section(3, Attrs, Content).
  377latex(p(Content)) -->
  378    [ nl_exact(2) ],
  379    latex(Content).
  380latex(blockquote(Content)) -->
  381    latex(cmd(begin(quote))),
  382    latex(Content),
  383    latex(cmd(end(quote))).
  384latex(center(Content)) -->
  385    latex(cmd(begin(center))),
  386    latex(Content),
  387    latex(cmd(end(center))).
  388latex(a(Attrs, Content)) -->
  389    { attribute(href(HREF), Attrs) },
  390    (   {HREF == Content}
  391    ->  latex(cmd(url(url_escape(HREF))))
  392    ;   { atom_concat(#,Sec,HREF) }
  393    ->  latex([Content, ' (', cmd(secref(Sec)), ')'])
  394    ;   latex(cmd(href(url_escape(HREF), Content)))
  395    ).
  396latex(br(_)) -->
  397    latex(latex(\\)).
  398latex(hr(_)) -->
  399    latex(cmd(hrule)).
  400latex(code(CodeList)) -->
  401    { is_list(CodeList),
  402      !,
  403      atomic_list_concat(CodeList, Atom)
  404    },
  405    (   {fragile}
  406    ->  latex(cmd(const(Atom)))
  407    ;   [ verb(Atom) ]
  408    ).
  409latex(code(Code)) -->
  410    { identifier(Code) },
  411    !,
  412    latex(cmd(const(Code))).
  413latex(code(Code)) -->
  414    (   {fragile}
  415    ->  latex(cmd(const(Code)))
  416    ;   [ verb(Code) ]
  417    ).
  418latex(b(Code)) -->
  419    latex(cmd(textbf(Code))).
  420latex(strong(Code)) -->
  421    latex(cmd(textbf(Code))).
  422latex(i(Code)) -->
  423    latex(cmd(textit(Code))).
  424latex(var(Var)) -->
  425    latex(cmd(arg(Var))).
  426latex(pre(_Class, Code)) -->
  427    [ nl_exact(2), code(Code), nl_exact(2) ].
  428latex(ul(Content)) -->
  429    { if_short_list(Content, shortlist, itemize, Env) },
  430    latex(cmd(begin(Env))),
  431    latex(Content),
  432    latex(cmd(end(Env))).
  433latex(ol(Content)) -->
  434    latex(cmd(begin(enumerate))),
  435    latex(Content),
  436    latex(cmd(end(enumerate))).
  437latex(li(Content)) -->
  438    latex(cmd(item)),
  439    latex(Content).
  440latex(dl(_, Content)) -->
  441    latex(cmd(begin(description))),
  442    latex(Content),
  443    latex(cmd(end(description))).
  444latex(dd(_, Content)) -->
  445    latex(Content).
  446latex(dd(Content)) -->
  447    latex(Content).
  448latex(dt(class=term, \term(Text, Term, Bindings))) -->
  449    termitem(Text, Term, Bindings).
  450latex(dt(Content)) -->
  451    latex(cmd(item(opt(Content)))).
  452latex(table(Attrs, Content)) -->
  453    latex_table(Attrs, Content).
  454latex(\Cmd, List, Tail) :-
  455    call(Cmd, List, Tail).
  456
  457% low level commands
  458latex(latex(Text)) -->
  459    [ latex(Text) ].
  460latex(cmd(Term)) -->
  461    { Term =.. [Cmd|Args] },
  462    indent(Cmd),
  463    [ cmd(Cmd) ],
  464    latex_arguments(Args),
  465    outdent(Cmd).
  466
  467indent(begin) --> !,           [ nl(2) ].
  468indent(end) --> !,             [ nl_exact(1) ].
  469indent(section) --> !,         [ nl(2) ].
  470indent(subsection) --> !,      [ nl(2) ].
  471indent(subsubsection) --> !,   [ nl(2) ].
  472indent(item) --> !,            [ nl(1), indent(4) ].
  473indent(definition) --> !,      [ nl(1), indent(4) ].
  474indent(tag) --> !,             [ nl(1), indent(4) ].
  475indent(termitem) --> !,        [ nl(1), indent(4) ].
  476indent(prefixtermitem) --> !,  [ nl(1), indent(4) ].
  477indent(infixtermitem) --> !,   [ nl(1), indent(4) ].
  478indent(postfixtermitem) --> !, [ nl(1), indent(4) ].
  479indent(predicate) --> !,       [ nl(1), indent(4) ].
  480indent(dcg) --> !,             [ nl(1), indent(4) ].
  481indent(infixop) --> !,         [ nl(1), indent(4) ].
  482indent(prefixop) --> !,        [ nl(1), indent(4) ].
  483indent(postfixop) --> !,       [ nl(1), indent(4) ].
  484indent(predicatesummary) --> !,[ nl(1) ].
  485indent(dcgsummary) --> !,      [ nl(1) ].
  486indent(oppredsummary) --> !,   [ nl(1) ].
  487indent(hline) --> !,           [ nl(1) ].
  488indent(_) -->                  [].
  489
  490outdent(begin) --> !,           [ nl_exact(1) ].
  491outdent(end) --> !,             [ nl(2) ].
  492outdent(item) --> !,            [ ' ' ].
  493outdent(tag) --> !,             [ nl(1) ].
  494outdent(termitem) --> !,        [ nl(1) ].
  495outdent(prefixtermitem) --> !,  [ nl(1) ].
  496outdent(infixtermitem) --> !,   [ nl(1) ].
  497outdent(postfixtermitem) --> !, [ nl(1) ].
  498outdent(definition) --> !,      [ nl(1) ].
  499outdent(section) --> !,         [ nl(2) ].
  500outdent(subsection) --> !,      [ nl(2) ].
  501outdent(subsubsection) --> !,   [ nl(2) ].
  502outdent(predicate) --> !,       [ nl(1) ].
  503outdent(dcg) --> !,             [ nl(1) ].
  504outdent(infixop) --> !,         [ nl(1) ].
  505outdent(prefixop) --> !,        [ nl(1) ].
  506outdent(postfixop) --> !,       [ nl(1) ].
  507outdent(predicatesummary) --> !,[ nl(1) ].
  508outdent(dcgsummary) --> !,      [ nl(1) ].
  509outdent(oppredsummary) --> !,   [ nl(1) ].
  510outdent(hline) --> !,           [ nl(1) ].
  511outdent(_) -->                  [].
  512
  513%!  latex_special(String, Rest)// is semidet.
  514%
  515%   Deals with special sequences of symbols.
  516
  517latex_special(In, Rest) -->
  518    { url_chars(In, Chars, Rest),
  519      special(Chars),
  520      atom_chars(Atom, Chars),
  521      urldef_name(Atom, Name)
  522    },
  523    !,
  524    latex([cmd(Name), latex('{}')]).
  525
  526special(Chars) :-
  527    memberchk(\, Chars),
  528    !.
  529special(Chars) :-
  530    length(Chars, Len),
  531    Len > 1.
  532
  533url_chars([H|T0], [H|T], Rest) :-
  534    urlchar(H),
  535    !,
  536    url_chars(T0, T, Rest).
  537url_chars(L, [], L).
  538
  539
  540%!  latex_arguments(+Args:list)// is det.
  541%
  542%   Write LaTeX command arguments. If  an   argument  is of the form
  543%   opt(Arg) it is written as  [Arg],   Otherwise  it  is written as
  544%   {Arg}. Note that opt([]) is omitted. I think no LaTeX command is
  545%   designed to handle an empty optional argument special.
  546%
  547%   During processing the arguments it asserts fragile/0 to allow is
  548%   taking care of LaTeX fragile   constructs  (i.e. constructs that
  549%   are not allows inside {...}).
  550
  551latex_arguments(List, Out, Tail) :-
  552    asserta(fragile, Ref),
  553    call_cleanup(fragile_list(List, Out, Tail),
  554                 erase(Ref)).
  555
  556fragile_list([]) --> [].
  557fragile_list([opt([])|T]) -->
  558    !,
  559    fragile_list(T).
  560fragile_list([opt(H)|T]) -->
  561    !,
  562    [ '[' ],
  563    latex_arg(H),
  564    [ ']' ],
  565    fragile_list(T).
  566fragile_list([H|T]) -->
  567    [ curl(open) ],
  568    latex_arg(H),
  569    [ curl(close) ],
  570    fragile_list(T).
  571
  572%!  latex_arg(+In)//
  573%
  574%   Write a LaTeX argument.  If  we  can,   we  will  use  a defined
  575%   urldef_name/2.
  576
  577latex_arg(H) -->
  578    { atomic(H),
  579      atom_string(Atom, H),
  580      urldef_name(Atom, Name)
  581    },
  582    !,
  583    latex(cmd(Name)).
  584latex_arg(H) -->
  585    { maplist(atom, H),
  586      atomic_list_concat(H, Atom),
  587      urldef_name(Atom, Name)
  588    },
  589    !,
  590    latex(cmd(Name)).
  591latex_arg(no_escape(Text)) -->
  592    !,
  593    [no_escape(Text)].
  594latex_arg(url_escape(Text)) -->
  595    !,
  596    [url_escape(Text)].
  597latex_arg(H) -->
  598    latex(H).
  599
  600attribute(Att, Attrs) :-
  601    is_list(Attrs),
  602    !,
  603    option(Att, Attrs).
  604attribute(Att, One) :-
  605    option(Att, [One]).
  606
  607if_short_list(Content, If, Else, Env) :-
  608    (   short_list(Content)
  609    ->  Env = If
  610    ;   Env = Else
  611    ).
  612
  613%!  short_list(+Content) is semidet.
  614%
  615%   True if Content describes the content of a dl or ul/ol list
  616%   where each elemenent has short content.
  617
  618short_list([]).
  619short_list([_,dd(Content)|T]) :-
  620    !,
  621    short_content(Content),
  622    short_list(T).
  623short_list([_,dd(_, Content)|T]) :-
  624    !,
  625    short_content(Content),
  626    short_list(T).
  627short_list([li(Content)|T]) :-
  628    short_content(Content),
  629    short_list(T).
  630
  631short_content(Content) :-
  632    phrase(latex(Content), Tokens),
  633    summed_string_len(Tokens, 0, Len),
  634    Len < 50.
  635
  636summed_string_len([], Len, Len).
  637summed_string_len([H|T], L0, L) :-
  638    atomic(H),
  639    !,
  640    atom_length(H, AL),
  641    L1 is L0 + AL,
  642    summed_string_len(T, L1, L).
  643summed_string_len([_|T], L0, L) :-
  644    summed_string_len(T, L0, L).
  645
  646
  647%!  latex_section(+Level, +Attributes, +Content)// is det.
  648%
  649%   Emit a LaTeX section,  keeping  track   of  the  desired highest
  650%   section level.
  651%
  652%   @param Level    Desired level, relative to the base-level.  Must
  653%                   be a non-negative integer.
  654
  655latex_section(Level, Attrs, Content) -->
  656    { current_options(Options),
  657      option(section_level(LaTexSection), Options, section),
  658      latex_section_level(LaTexSection, BaseLevel),
  659      FinalLevel is BaseLevel+Level,
  660      (   latex_section_level(SectionCommand, FinalLevel)
  661      ->  Term =.. [SectionCommand, Content]
  662      ;   domain_error(latex_section_level, FinalLevel)
  663      )
  664    },
  665    latex(cmd(Term)),
  666    section_label(Attrs).
  667
  668section_label(Attrs) -->
  669    { is_list(Attrs),
  670      memberchk(id(Name), Attrs),
  671      !,
  672      delete_unsafe_label_chars(Name, SafeName),
  673      atom_concat('sec:', SafeName, Label)
  674    },
  675    latex(cmd(label(Label))).
  676section_label(_) -->
  677    [].
  678
  679latex_section_level(chapter,       0).
  680latex_section_level(section,       1).
  681latex_section_level(subsection,    2).
  682latex_section_level(subsubsection, 3).
  683latex_section_level(paragraph,     4).
  684
  685deepen_section_level(Level0, Level1) :-
  686    latex_section_level(Level0, N),
  687    N1 is N + 1,
  688    latex_section_level(Level1, N1).
  689
  690%!  delete_unsafe_label_chars(+LabelIn, -LabelOut)
  691%
  692%   delete unsafe characters from LabelIn. Currently only deletes _,
  693%   as this appears  commonly  through   filenames,  but  cannot  be
  694%   handled through the LaTeX processing chain.
  695
  696delete_unsafe_label_chars(LabelIn, LabelOut) :-
  697    atom_chars(LabelIn, Chars),
  698    delete(Chars, '_', CharsOut),
  699    atom_chars(LabelOut, CharsOut).
  700
  701
  702                 /*******************************
  703                 *         \ COMMANDS           *
  704                 *******************************/
  705
  706%!  include(+File, +Type, +Options)// is det.
  707%
  708%   Called from [[File]].
  709
  710include(PI, predicate, _) -->
  711    !,
  712    (   {   options(Options)
  713        ->  true
  714        ;   Options = []
  715        },
  716        latex_tokens_for_predicates(PI, Options)
  717    ->  []
  718    ;   latex(cmd(item(['[[', \predref(PI), ']]'])))
  719    ).
  720include(File, Type, Options) -->
  721    { existing_linked_file(File, Path) },
  722    !,
  723    include_file(Path, Type, Options).
  724include(File, _, _) -->
  725    latex(code(['[[', File, ']]'])).
  726
  727include_file(Path, image, Options) -->
  728    { option(caption(Caption), Options) },
  729    !,
  730    latex(cmd(begin(figure, [no_escape(htbp)]))),
  731    latex(cmd(begin(center))),
  732    latex(cmd(includegraphics(Path))),
  733    latex(cmd(end(center))),
  734    latex(cmd(caption(Caption))),
  735    latex(cmd(end(figure))).
  736include_file(Path, image, _) -->
  737    !,
  738    latex(cmd(includegraphics(Path))).
  739include_file(Path, Type, _) -->
  740    { assertion(memberchk(Type, [prolog,wiki])),
  741      current_options(Options0),
  742      select_option(stand_alone(_), Options0, Options1, _),
  743      select_option(section_level(Level0), Options1, Options2, section),
  744      deepen_section_level(Level0, Level),
  745      Options = [stand_alone(false), section_level(Level)|Options2]
  746    },
  747    (   {Type == prolog}
  748    ->  latex_tokens_for_file(Path, Options)
  749    ;   latex_tokens_for_wiki_file(Path, Options)
  750    ).
  751
  752%!  file(+File, +Options)// is det.
  753%
  754%   Called from implicitely linked files.  The HTML version creates
  755%   a hyperlink.  We just name the file.
  756
  757file(File, _Options) -->
  758    { fragile },
  759    !,
  760    latex(cmd(texttt(File))).
  761file(File, _Options) -->
  762    latex(cmd(file(File))).
  763
  764%!  predref(+PI)// is det.
  765%
  766%   Called  from  name/arity  or   name//arity    patterns   in  the
  767%   documentation.
  768
  769predref(Module:Name/Arity) -->
  770    !,
  771    latex(cmd(qpredref(Module, Name, Arity))).
  772predref(Module:Name//Arity) -->
  773    latex(cmd(qdcgref(Module, Name, Arity))).
  774predref(Name/Arity) -->
  775    latex(cmd(predref(Name, Arity))).
  776predref(Name//Arity) -->
  777    latex(cmd(dcgref(Name, Arity))).
  778
  779%!  nopredref(+PI)//
  780%
  781%   Called from ``name/arity``.
  782
  783nopredref(Name/Arity) -->
  784    latex(cmd(nopredref(Name, Arity))).
  785
  786%!  flagref(+Flag)//
  787%
  788%   Reference to a Prolog flag
  789
  790flagref(Flag) -->
  791    latex(cmd(prologflag(Flag))).
  792
  793%!  cite(+Citations) is det.
  794%
  795%   Emit a ``\cite{Citations}`` command
  796
  797cite(Citations) -->
  798    { atomic_list_concat(Citations, ',', Atom) },
  799    latex(cmd(cite(Atom))).
  800
  801%!  tags(+Tags:list(Tag)) is det.
  802%
  803%   Emit tag list produced by the   Wiki processor from the @keyword
  804%   commands.
  805
  806tags([\args(Params)|Rest]) -->
  807    !,
  808    args(Params),
  809    tags_list(Rest).
  810tags(List) -->
  811    tags_list(List).
  812
  813tags_list([]) -->
  814    [].
  815tags_list(List) -->
  816    [ nl(2) ],
  817    latex(cmd(begin(tags))),
  818    latex(List),
  819    latex(cmd(end(tags))),
  820    [ nl(2) ].
  821
  822%!  tag(+Tag, +Values:list)// is det.
  823%
  824%   Called from \tag(Name, Values) terms produced by doc_wiki.pl.
  825
  826tag(Tag, [One]) -->
  827    !,
  828    { doc_tag_title(Tag, Title) },
  829    latex([ cmd(tag(Title))
  830          | One
  831          ]).
  832tag(Tag, More) -->
  833    { doc_tag_title(Tag, Title) },
  834    latex([ cmd(mtag(Title)),
  835            \tag_value_list(More)
  836          ]).
  837
  838tag_value_list([H|T]) -->
  839    latex(['- '|H]),
  840    (   { T \== [] }
  841    ->  [latex(' \\\\')],
  842        tag_value_list(T)
  843    ;   []
  844    ).
  845
  846%!  args(+Params:list) is det.
  847%
  848%   Called from \args(List) created by   doc_wiki.pl.  Params is a
  849%   list of arg(Name, Descr).
  850
  851args(Params) -->
  852    latex([ cmd(begin(arguments)),
  853            \arg_list(Params),
  854            cmd(end(arguments))
  855          ]).
  856
  857arg_list([]) -->
  858    [].
  859arg_list([H|T]) -->
  860    argument(H),
  861    arg_list(T).
  862
  863argument(arg(Name,Descr)) -->
  864    [ nl(1) ],
  865    latex(cmd(arg(Name))), [ latex(' & ') ],
  866    latex(Descr), [latex(' \\\\')].
  867
  868%!  file_header(+File, +Options)// is det.
  869%
  870%   Create the file header.
  871
  872file_header(File, Options) -->
  873    { memberchk(file(Title, Comment), Options),
  874      !,
  875      file_synopsis(File, Synopsis)
  876    },
  877    file_title([Synopsis, ': ', Title], File, Options),
  878    { is_structured_comment(Comment, Prefixes),
  879      string_codes(Comment, Codes),
  880      indented_lines(Codes, Prefixes, Lines),
  881      section_comment_header(Lines, _Header, Lines1),
  882      wiki_lines_to_dom(Lines1, [], DOM0),
  883      tags_to_front(DOM0, DOM)
  884    },
  885    latex(DOM),
  886    latex(cmd(vspace('0.7cm'))).
  887file_header(File, Options) -->
  888    { file_synopsis(File, Synopsis)
  889    },
  890    file_title([Synopsis], File, Options).
  891
  892tags_to_front(DOM0, DOM) :-
  893    append(Content, [\tags(Tags)], DOM0),
  894    !,
  895    DOM = [\tags(Tags)|Content].
  896tags_to_front(DOM, DOM).
  897
  898file_synopsis(File, Synopsis) :-
  899    file_name_on_path(File, Term),
  900    unquote_filespec(Term, Unquoted),
  901    format(atom(Synopsis), '~w', [Unquoted]).
  902
  903
  904%!  file_title(+Title:list, +File, +Options)// is det
  905%
  906%   Emit the file-header and manipulation buttons.
  907
  908file_title(Title, File, Options) -->
  909    { option(section_level(Level), Options, section),
  910      Section =.. [Level,Title],
  911      file_base_name(File, BaseExt),
  912      file_name_extension(Base, _, BaseExt),
  913      delete_unsafe_label_chars(Base, SafeBase),
  914      atom_concat('sec:', SafeBase, Label)
  915    },
  916    latex(cmd(Section)),
  917    latex(cmd(label(Label))).
  918
  919
  920%!  objects(+Objects:list, +Options)// is det.
  921%
  922%   Emit the documentation body.
  923
  924objects(Objects, Options) -->
  925    objects(Objects, [body], Options).
  926
  927objects([], Mode, _) -->
  928    pop_mode(body, Mode, _).
  929objects([Obj|T], Mode, Options) -->
  930    object(Obj, Mode, Mode1, Options),
  931    objects(T, Mode1, Options).
  932
  933object(doc(Obj,Pos,Comment), Mode0, Mode, Options) -->
  934    !,
  935    object(Obj, Pos, Comment, Mode0, Mode, Options).
  936object(Obj, Mode0, Mode, Options) -->
  937    { doc_comment(Obj, Pos, _Summary, Comment)
  938    },
  939    !,
  940    object(Obj, Pos, Comment, Mode0, Mode, Options).
  941
  942object(Obj, Pos, Comment, Mode0, Mode, Options) -->
  943    { is_pi(Obj),
  944      !,
  945      is_structured_comment(Comment, Prefixes),
  946      string_codes(Comment, Codes),
  947      indented_lines(Codes, Prefixes, Lines),
  948      strip_module(user:Obj, Module, _),
  949      process_modes(Lines, Module, Pos, Modes, Args, Lines1),
  950      (   private(Obj, Options)
  951      ->  Class = privdef           % private definition
  952      ;   multifile(Obj, Options)
  953      ->  Class = multidef
  954      ;   Class = pubdef            % public definition
  955      ),
  956      (   Obj = Module:_
  957      ->  POptions = [module(Module)|Options]
  958      ;   POptions = Options
  959      ),
  960      DOM = [\pred_dt(Modes, Class, POptions), dd(class=defbody, DOM1)],
  961      wiki_lines_to_dom(Lines1, Args, DOM0),
  962      strip_leading_par(DOM0, DOM1),
  963      assert_documented(Obj)
  964    },
  965    need_mode(description, Mode0, Mode),
  966    latex(DOM).
  967object([Obj|Same], Pos, Comment, Mode0, Mode, Options) -->
  968    !,
  969    object(Obj, Pos, Comment, Mode0, Mode, Options),
  970    { maplist(assert_documented, Same) }.
  971object(Obj, _Pos, _Comment, Mode, Mode, _Options) -->
  972    { debug(pldoc, 'Skipped ~p', [Obj]) },
  973    [].
  974
  975assert_documented(Obj) :-
  976    assert(documented(Obj)).
  977
  978
  979%!  need_mode(+Mode:atom, +Stack:list, -NewStack:list)// is det.
  980%
  981%   While predicates are part of a   description  list, sections are
  982%   not and we therefore  need  to   insert  <dl>...</dl>  into  the
  983%   output. We do so by demanding  an outer environment and push/pop
  984%   the required elements.
  985
  986need_mode(Mode, Stack, Stack) -->
  987    { Stack = [Mode|_] },
  988    !,
  989    [].
  990need_mode(Mode, Stack, Rest) -->
  991    { memberchk(Mode, Stack)
  992    },
  993    !,
  994    pop_mode(Mode, Stack, Rest).
  995need_mode(Mode, Stack, [Mode|Stack]) -->
  996    !,
  997    latex(cmd(begin(Mode))).
  998
  999pop_mode(Mode, Stack, Stack) -->
 1000    { Stack = [Mode|_] },
 1001    !,
 1002    [].
 1003pop_mode(Mode, [H|Rest0], Rest) -->
 1004    latex(cmd(end(H))),
 1005    pop_mode(Mode, Rest0, Rest).
 1006
 1007
 1008%!  pred_dt(+Modes, +Class, Options)// is det.
 1009%
 1010%   Emit the \predicate{}{}{} header.
 1011%
 1012%   @param Modes    List as returned by process_modes/5.
 1013%   @param Class    One of =privdef= or =pubdef=.
 1014%
 1015%   @tbd    Determinism
 1016
 1017pred_dt(Modes, Class, Options) -->
 1018    [nl(2)],
 1019    pred_dt(Modes, [], _Done, [class(Class)|Options]).
 1020
 1021pred_dt([], Done, Done, _) -->
 1022    [].
 1023pred_dt([H|T], Done0, Done, Options) -->
 1024    pred_mode(H, Done0, Done1, Options),
 1025    (   {T == []}
 1026    ->  []
 1027    ;   latex(cmd(nodescription)),
 1028        pred_dt(T, Done1, Done, Options)
 1029    ).
 1030
 1031pred_mode(mode(Head,Vars), Done0, Done, Options) -->
 1032    !,
 1033    { bind_vars(Head, Vars) },
 1034    pred_mode(Head, Done0, Done, Options).
 1035pred_mode(Head is Det, Done0, Done, Options) -->
 1036    !,
 1037    anchored_pred_head(Head, Done0, Done, [det(Det)|Options]).
 1038pred_mode(Head, Done0, Done, Options) -->
 1039    anchored_pred_head(Head, Done0, Done, Options).
 1040
 1041bind_vars(Term, Bindings) :-
 1042    bind_vars(Bindings),
 1043    anon_vars(Term).
 1044
 1045bind_vars([]).
 1046bind_vars([Name=Var|T]) :-
 1047    Var = '$VAR'(Name),
 1048    bind_vars(T).
 1049
 1050%!  anon_vars(+Term) is det.
 1051%
 1052%   Bind remaining variables in Term to '$VAR'('_'), so they are
 1053%   printed as '_'.
 1054
 1055anon_vars(Var) :-
 1056    var(Var),
 1057    !,
 1058    Var = '$VAR'('_').
 1059anon_vars(Term) :-
 1060    compound(Term),
 1061    !,
 1062    Term =.. [_|Args],
 1063    maplist(anon_vars, Args).
 1064anon_vars(_).
 1065
 1066
 1067anchored_pred_head(Head, Done0, Done, Options) -->
 1068    { pred_anchor_name(Head, PI, _Name) },
 1069    (   { memberchk(PI, Done0) }
 1070    ->  { Done = Done0 }
 1071    ;   { Done = [PI|Done0] }
 1072    ),
 1073    pred_head(Head, Options).
 1074
 1075
 1076%!  pred_head(+Term, Options) is det.
 1077%
 1078%   Emit a predicate head. The functor is  typeset as a =span= using
 1079%   class =pred= and the arguments and =var= using class =arglist=.
 1080%
 1081%   @tbd Support determinism in operators
 1082
 1083pred_head(//(Head), Options) -->
 1084    !,
 1085    { pred_attributes(Options, Atts),
 1086      Head =.. [Functor|Args],
 1087      length(Args, Arity)
 1088    },
 1089    latex(cmd(dcg(opt(Atts), Functor, Arity, \pred_args(Args, 1)))).
 1090pred_head(Head, _Options) -->                   % Infix operators
 1091    { Head =.. [Functor,Left,Right],
 1092      Functor \== (:),
 1093      is_op_type(Functor, infix), !
 1094    },
 1095    latex(cmd(infixop(Functor, \pred_arg(Left, 1), \pred_arg(Right, 2)))).
 1096pred_head(Head, _Options) -->                   % Prefix operators
 1097    { Head =.. [Functor,Arg],
 1098      is_op_type(Functor, prefix), !
 1099    },
 1100    latex(cmd(prefixop(Functor, \pred_arg(Arg, 1)))).
 1101pred_head(Head, _Options) -->                   % Postfix operators
 1102    { Head =.. [Functor,Arg],
 1103      is_op_type(Functor, postfix), !
 1104    },
 1105    latex(cmd(postfixop(Functor, \pred_arg(Arg, 1)))).
 1106pred_head(M:Head, Options) -->                 % Qualified predicates
 1107    !,
 1108    { pred_attributes(Options, Atts),
 1109      Head =.. [Functor|Args],
 1110      length(Args, Arity)
 1111    },
 1112    latex(cmd(qpredicate(opt(Atts),
 1113                         M,
 1114                         Functor, Arity, \pred_args(Args, 1)))).
 1115pred_head(Head, Options) -->                    % Plain terms
 1116    { pred_attributes(Options, Atts),
 1117      Head =.. [Functor|Args],
 1118      length(Args, Arity)
 1119    },
 1120    latex(cmd(predicate(opt(Atts),
 1121                        Functor, Arity, \pred_args(Args, 1)))).
 1122
 1123%!  pred_attributes(+Options, -Attributes) is det.
 1124%
 1125%   Create a comma-separated list of   predicate attributes, such as
 1126%   determinism, etc.
 1127
 1128pred_attributes(Options, Attrs) :-
 1129    findall(A, pred_att(Options, A), As),
 1130    insert_comma(As, Attrs).
 1131
 1132pred_att(Options, Det) :-
 1133    option(det(Det), Options).
 1134pred_att(Options, private) :-
 1135    option(class(privdef), Options).
 1136pred_att(Options, multifile) :-
 1137    option(class(multidef), Options).
 1138
 1139insert_comma([H1,H2|T0], [H1, ','|T]) :-
 1140    !,
 1141    insert_comma([H2|T0], T).
 1142insert_comma(L, L).
 1143
 1144
 1145:- if(current_predicate(is_dict/1)). 1146dict_kv_pairs([]) --> [].
 1147dict_kv_pairs([H|T]) -->
 1148    dict_kv(H),
 1149    (   { T == [] }
 1150    ->  []
 1151    ;   latex(', '),
 1152        dict_kv_pairs(T)
 1153    ).
 1154
 1155dict_kv(Key-Value) -->
 1156    latex(cmd(key(Key))),
 1157    latex(':'),
 1158    term(Value).
 1159:- endif. 1160
 1161pred_args([], _) -->
 1162    [].
 1163pred_args([H|T], I) -->
 1164    pred_arg(H, I),
 1165    (   {T==[]}
 1166    ->  []
 1167    ;   latex(', '),
 1168        { I2 is I + 1 },
 1169        pred_args(T, I2)
 1170    ).
 1171
 1172pred_arg(Var, I) -->
 1173    { var(Var) },
 1174    !,
 1175    latex(['Arg', I]).
 1176pred_arg(...(Term), I) -->
 1177    !,
 1178    pred_arg(Term, I),
 1179    latex(cmd(ldots)).
 1180pred_arg(Term, I) -->
 1181    { Term =.. [Ind,Arg],
 1182      mode_indicator(Ind)
 1183    },
 1184    !,
 1185    latex([Ind, \pred_arg(Arg, I)]).
 1186pred_arg(Arg:Type, _) -->
 1187    !,
 1188    latex([\argname(Arg), :, \argtype(Type)]).
 1189pred_arg(Arg, _) -->
 1190    { atom(Arg) },
 1191    !,
 1192    argname(Arg).
 1193pred_arg(Arg, _) -->
 1194    argtype(Arg).                   % arbitrary term
 1195
 1196argname('$VAR'(Name)) -->
 1197    !,
 1198    latex(Name).
 1199argname(Name) -->
 1200    !,
 1201    latex(Name).
 1202
 1203argtype(Term) -->
 1204    { format(string(S), '~W',
 1205             [ Term,
 1206               [ quoted(true),
 1207                 numbervars(true)
 1208               ]
 1209             ]) },
 1210    latex(S).
 1211
 1212%!  term(+Text, +Term, +Bindings)// is det.
 1213%
 1214%   Process the \term element as produced by doc_wiki.pl.
 1215%
 1216%   @tbd    Properly merge with pred_head//1
 1217
 1218term(_, Term, Bindings) -->
 1219    { bind_vars(Bindings) },
 1220    term(Term).
 1221
 1222term('$VAR'(Name)) -->
 1223    !,
 1224    latex(cmd(arg(Name))).
 1225term(Compound) -->
 1226    { callable(Compound),
 1227      !,
 1228      Compound =.. [Functor|Args]
 1229    },
 1230    !,
 1231    term_with_args(Functor, Args).
 1232term(Rest) -->
 1233    latex(Rest).
 1234
 1235term_with_args(Functor, [Left, Right]) -->
 1236    { is_op_type(Functor, infix) },
 1237    !,
 1238    latex(cmd(infixterm(Functor, \term(Left), \term(Right)))).
 1239term_with_args(Functor, [Arg]) -->
 1240    { is_op_type(Functor, prefix) },
 1241    !,
 1242    latex(cmd(prefixterm(Functor, \term(Arg)))).
 1243term_with_args(Functor, [Arg]) -->
 1244    { is_op_type(Functor, postfix) },
 1245    !,
 1246    latex(cmd(postfixterm(Functor, \term(Arg)))).
 1247term_with_args(Functor, Args) -->
 1248    latex(cmd(term(Functor, \pred_args(Args, 1)))).
 1249
 1250
 1251%!  termitem(+Text, +Term, +Bindings)// is det.
 1252%
 1253%   Create a termitem or one of its variations.
 1254
 1255termitem(_Text, Term, Bindings) -->
 1256    { bind_vars(Bindings) },
 1257    termitem(Term).
 1258
 1259termitem('$VAR'(Name)) -->
 1260    !,
 1261    latex(cmd(termitem(var(Name), ''))).
 1262:- if(current_predicate(is_dict/1)). 1263termitem(Dict) -->
 1264    { is_dict(Dict),
 1265      !,
 1266      dict_pairs(Dict, Tag, Pairs)
 1267    },
 1268    latex(cmd(dictitem(Tag, \dict_kv_pairs(Pairs)))).
 1269:- endif. 1270termitem(Compound) -->
 1271    { callable(Compound),
 1272      !,
 1273      Compound =.. [Functor|Args]
 1274    },
 1275    !,
 1276    termitem_with_args(Functor, Args).
 1277termitem(Rest) -->
 1278    latex(cmd(termitem(Rest, ''))).
 1279
 1280termitem_with_args(Functor, [Left, Right]) -->
 1281    { is_op_type(Functor, infix) },
 1282    !,
 1283    latex(cmd(infixtermitem(Functor, \term(Left), \term(Right)))).
 1284termitem_with_args(Functor, [Arg]) -->
 1285    { is_op_type(Functor, prefix) },
 1286    !,
 1287    latex(cmd(prefixtermitem(Functor, \term(Arg)))).
 1288termitem_with_args(Functor, [Arg]) -->
 1289    { is_op_type(Functor, postfix) },
 1290    !,
 1291    latex(cmd(postfixtermitem(Functor, \term(Arg)))).
 1292termitem_with_args({}, [Arg]) -->
 1293    !,
 1294    latex(cmd(curltermitem(\argtype(Arg)))).
 1295termitem_with_args(Functor, Args) -->
 1296    latex(cmd(termitem(Functor, \pred_args(Args, 1)))).
 1297
 1298
 1299%!  latex_table(+Attrs, +Content)// is det.
 1300%
 1301%   Emit a table in LaTeX.
 1302
 1303latex_table(_Attrs, Content) -->
 1304    { max_columns(Content, 0, _, -, Wittness),
 1305      col_align(Wittness, 1, Content, Align),
 1306      atomics_to_string(Align, '|', S0),
 1307      atomic_list_concat(['|',S0,'|'], Format)
 1308    },
 1309%       latex(cmd(begin(table, opt(h)))),
 1310    latex(cmd(begin(quote))),
 1311    latex(cmd(begin(tabulary,
 1312                    no_escape('0.9\\textwidth'),
 1313                    no_escape(Format)))),
 1314    latex(cmd(hline)),
 1315    rows(Content),
 1316    latex(cmd(hline)),
 1317    latex(cmd(end(tabulary))),
 1318    latex(cmd(end(quote))).
 1319%       latex(cmd(end(table))).
 1320
 1321max_columns([], C, C, W, W).
 1322max_columns([tr(List)|T], C0, C, _, W) :-
 1323    length(List, C1),
 1324    C1 >= C0,		% take last as wittness to avoid getting the header
 1325    !,
 1326    max_columns(T, C1, C, List, W).
 1327max_columns([_|T], C0, C, W0, W) :-
 1328    max_columns(T, C0, C, W0, W).
 1329
 1330col_align([], _, _, []).
 1331col_align([CH|CT], Col, Rows, [AH|AT]) :-
 1332    (   member(tr(Cells), Rows),
 1333        nth1(Col, Cells, Cell),
 1334        auto_par(Cell)
 1335    ->  Wrap = auto
 1336    ;   Wrap = false
 1337    ),
 1338    col_align(CH, Wrap, AH),
 1339    Col1 is Col+1,
 1340    col_align(CT, Col1, Rows, AT).
 1341
 1342col_align(td(class=Class,_), Wrap, Align) :-
 1343    align_class(Class, Wrap, Align),
 1344    !.
 1345col_align(_, auto, 'L') :- !.
 1346col_align(_, false, 'l').
 1347
 1348align_class(left,   auto, 'L').
 1349align_class(center, auto, 'C').
 1350align_class(right,  auto, 'R').
 1351align_class(left,   false, 'l').
 1352align_class(center, false, 'c').
 1353align_class(right,  false, 'r').
 1354
 1355rows([]) -->
 1356    [].
 1357rows([tr(Content)|T]) -->
 1358    row(Content),
 1359    rows(T).
 1360
 1361row([]) -->
 1362    [ latex(' \\\\'), nl(1) ].
 1363row([td(_Attrs, Content)|T]) -->
 1364    !,
 1365    row([td(Content)|T]).
 1366row([td(Content)|T]) -->
 1367    latex(Content),
 1368    (   {T == []}
 1369    ->  []
 1370    ;   [ latex(' & ') ]
 1371    ),
 1372    row(T).
 1373row([th(Content)|T]) -->
 1374    latex(cmd(textbf(Content))),
 1375    (   {T == []}
 1376    ->  []
 1377    ;   [ latex(' & ') ]
 1378    ),
 1379    row(T).
 1380
 1381%!  auto_par(+Content) is semidet.
 1382%
 1383%   True when cell Content is a good candidate for auto-wrapping.
 1384
 1385auto_par(Content) :-
 1386    phrase(html_text(Content), Words),
 1387    length(Words, WC),
 1388    WC > 1,
 1389    atomics_to_string(Words, Text),
 1390    string_length(Text, Width),
 1391    Width > 15.
 1392
 1393html_text([]) -->
 1394    !.
 1395html_text([H|T]) -->
 1396    !,
 1397    html_text(H),
 1398    html_text(T).
 1399html_text(\predref(Name/Arity)) -->
 1400    !,
 1401    { format(string(S), '~q/~q', [Name, Arity]) },
 1402    [S].
 1403html_text(Compound) -->
 1404    { compound(Compound),
 1405      !,
 1406      functor(Compound, _Name, Arity),
 1407      arg(Arity, Compound, Content)
 1408    },
 1409    html_text(Content).
 1410html_text(Word) -->
 1411    [Word].
 1412
 1413
 1414
 1415
 1416                 /*******************************
 1417                 *      SUMMARY PROCESSING      *
 1418                 *******************************/
 1419
 1420%!  latex_summary(+Options)
 1421%
 1422%   If Options contains  summary(+File),  write   a  summary  of all
 1423%   documented predicates to File.
 1424
 1425latex_summary(Options) :-
 1426    option(summary(File), Options),
 1427    !,
 1428    findall(Obj, summary_obj(Obj), Objs),
 1429    maplist(pi_sort_key, Objs, Keyed),
 1430    keysort(Keyed, KSorted),
 1431    pairs_values(KSorted, SortedObj),
 1432    phrase(summarylist(SortedObj, Options), Tokens),
 1433    open(File, write, Out),
 1434    call_cleanup(print_latex(Out, Tokens, Options),
 1435                 close(Out)).
 1436latex_summary(_) :-
 1437    retractall(documented(_)).
 1438
 1439summary_obj(Obj) :-
 1440    documented(Obj),
 1441    pi_head(Obj, Head),
 1442    \+ xref_hook(Head).
 1443
 1444pi_head(M:PI, M:Head) :-
 1445    !,
 1446    pi_head(PI, Head).
 1447pi_head(Name/Arity, Head) :-
 1448    functor(Head, Name, Arity).
 1449pi_head(Name//DCGArity, Head) :-
 1450    Arity is DCGArity+2,
 1451    functor(Head, Name, Arity).
 1452
 1453
 1454pi_sort_key(M:PI, PI-(M:PI)) :- !.
 1455pi_sort_key(PI, PI-PI).
 1456
 1457object_name_arity(_:Term, Type, Name, Arity) :-
 1458    nonvar(Term),
 1459    !,
 1460    object_name_arity(Term, Type, Name, Arity).
 1461object_name_arity(Name/Arity, pred, Name, Arity).
 1462object_name_arity(Name//Arity, dcg, Name, Arity).
 1463
 1464summarylist(Objs, Options) -->
 1465    latex(cmd(begin(summarylist, ll))),
 1466    summary(Objs, Options),
 1467    latex(cmd(end(summarylist))).
 1468
 1469summary([], _) -->
 1470    [].
 1471summary([H|T], Options) -->
 1472    summary_line(H, Options),
 1473    summary(T, Options).
 1474
 1475summary_line(Obj, _Options) -->
 1476    { doc_comment(Obj, _Pos, Summary, _Comment),
 1477      !,
 1478      atom_codes(Summary, Codes),
 1479      phrase(pldoc_wiki:line_tokens(Tokens), Codes), % TBD: proper export
 1480      object_name_arity(Obj, Type, Name, Arity)
 1481    },
 1482    (   {Type == dcg}
 1483    ->  latex(cmd(dcgsummary(Name, Arity, Tokens)))
 1484    ;   { strip_module(Obj, M, _),
 1485          current_op(Pri, Ass, M:Name)
 1486        }
 1487    ->  latex(cmd(oppredsummary(Name, Arity, Ass, Pri, Tokens)))
 1488    ;   latex(cmd(predicatesummary(Name, Arity, Tokens)))
 1489    ).
 1490summary_line(Obj, _Options) -->
 1491    { print_message(warning, pldoc(no_summary_for(Obj)))
 1492    }.
 1493
 1494                 /*******************************
 1495                 *          PRINT TOKENS        *
 1496                 *******************************/
 1497
 1498print_latex(Out, Tokens, Options) :-
 1499    latex_header(Out, Options),
 1500    print_latex_tokens(Tokens, Out),
 1501    latex_footer(Out, Options).
 1502
 1503
 1504%!  print_latex_tokens(+Tokens, +Out)
 1505%
 1506%   Print primitive LaTeX tokens to Output
 1507
 1508print_latex_tokens([], _).
 1509print_latex_tokens([nl(N)|T0], Out) :-
 1510    !,
 1511    max_nl(T0, T, N, NL),
 1512    nl(Out, NL),
 1513    print_latex_tokens(T, Out).
 1514print_latex_tokens([nl_exact(N)|T0], Out) :-
 1515    !,
 1516    nl_exact(T0, T,N, NL),
 1517    nl(Out, NL),
 1518    print_latex_tokens(T, Out).
 1519print_latex_tokens([H|T], Out) :-
 1520    print_latex_token(H, Out),
 1521    print_latex_tokens(T, Out).
 1522
 1523print_latex_token(cmd(Cmd), Out) :-
 1524    !,
 1525    format(Out, '\\~w', [Cmd]).
 1526print_latex_token(curl(open), Out) :-
 1527    !,
 1528    format(Out, '{', []).
 1529print_latex_token(curl(close), Out) :-
 1530    !,
 1531    format(Out, '}', []).
 1532print_latex_token(indent(N), Out) :-
 1533    !,
 1534    format(Out, '~t~*|', [N]).
 1535print_latex_token(nl(N), Out) :-
 1536    !,
 1537    format(Out, '~N', []),
 1538    forall(between(2,N,_), nl(Out)).
 1539print_latex_token(verb(Verb), Out) :-
 1540    is_list(Verb), Verb \== [],
 1541    !,
 1542    atomic_list_concat(Verb, Atom),
 1543    print_latex_token(verb(Atom), Out).
 1544print_latex_token(verb(Verb), Out) :-
 1545    !,
 1546    (   member(C, [$,'|',@,=,'"',^,!]),
 1547        \+ sub_atom(Verb, _, _, _, C)
 1548    ->  atom_replace_char(Verb, '\n', ' ', Verb2),
 1549        format(Out, '\\verb~w~w~w', [C,Verb2,C])
 1550    ;   assertion(fail)
 1551    ).
 1552print_latex_token(code(Code), Out) :-
 1553    !,
 1554    format(Out, '~N\\begin{code}~n', []),
 1555    format(Out, '~w', [Code]),
 1556    format(Out, '~N\\end{code}', []).
 1557print_latex_token(latex(Code), Out) :-
 1558    !,
 1559    write(Out, Code).
 1560print_latex_token(w(Word), Out) :-
 1561    !,
 1562    print_latex(Out, Word).
 1563print_latex_token(no_escape(Text), Out) :-
 1564    !,
 1565    write(Out, Text).
 1566print_latex_token(url_escape(Text), Out) :-
 1567    !,
 1568    print_url(Out, Text).
 1569print_latex_token(Rest, Out) :-
 1570    (   atomic(Rest)
 1571    ->  print_latex(Out, Rest)
 1572    ;   %type_error(latex_token, Rest)
 1573        write(Out, Rest)
 1574    ).
 1575
 1576atom_replace_char(In, From, To, Out) :-
 1577    sub_atom(In, _, _, _, From),
 1578    !,
 1579    atom_chars(In, CharsIn),
 1580    replace(CharsIn, From, To, CharsOut),
 1581    atom_chars(Out, CharsOut).
 1582atom_replace_char(In, _, _, In).
 1583
 1584replace([], _, _, []).
 1585replace([H|T0], H, N, [N|T]) :-
 1586    !,
 1587    replace(T0, H, N, T).
 1588replace([H|T0], F, N, [H|T]) :-
 1589    replace(T0, F, N, T).
 1590
 1591
 1592%!  print_latex(+Out, +Text:atomic) is det.
 1593%
 1594%   Print Text, such that it comes out as normal LaTeX text.
 1595
 1596print_latex(Out, String) :-
 1597    atom_string(Atom, String),
 1598    atom_chars(Atom, Chars),
 1599    print_chars(Chars, Out).
 1600
 1601print_chars([], _).
 1602print_chars([H|T], Out) :-
 1603    print_char(H, Out),
 1604    print_chars(T, Out).
 1605
 1606
 1607print_url(Out, String) :-
 1608    string_chars(String, Chars),
 1609    print_url_chars(Chars, Out).
 1610
 1611print_url_chars([], _).
 1612print_url_chars([H|T], Out) :-
 1613    print_url_char(H, Out),
 1614    print_url_chars(T, Out).
 1615
 1616print_url_char('#', Out) :- !, write(Out, '\\#').
 1617print_url_char(C,   Out) :- put_char(Out, C).
 1618
 1619
 1620%!  max_nl(T0, T, M0, M)
 1621%
 1622%   Remove leading sequence of nl(N) and return the maximum of it.
 1623
 1624max_nl([nl(M1)|T0], T, M0, M) :-
 1625    !,
 1626    M2 is max(M1, M0),
 1627    max_nl(T0, T, M2, M).
 1628max_nl([nl_exact(M1)|T0], T, _, M) :-
 1629    !,
 1630    nl_exact(T0, T, M1, M).
 1631max_nl(T, T, M, M).
 1632
 1633nl_exact([nl(_)|T0], T, M0, M) :-
 1634    !,
 1635    max_nl(T0, T, M0, M).
 1636nl_exact([nl_exact(M1)|T0], T, M0, M) :-
 1637    !,
 1638    M2 is max(M1, M0),
 1639    max_nl(T0, T, M2, M).
 1640nl_exact(T, T, M, M).
 1641
 1642
 1643nl(Out, N) :-
 1644    forall(between(1, N, _), nl(Out)).
 1645
 1646
 1647%!  print_char(+Char, +Out) is det.
 1648%
 1649%   Write Char in LaTeX format to Out. This escapes characters for LaTeX
 1650%   where necessary.
 1651
 1652print_char('<', Out) :- !, write(Out, '$<$').
 1653print_char('>', Out) :- !, write(Out, '$>$').
 1654print_char('{', Out) :- !, write(Out, '\\{').
 1655print_char('}', Out) :- !, write(Out, '\\}').
 1656print_char('$', Out) :- !, write(Out, '\\$').
 1657print_char('&', Out) :- !, write(Out, '\\&').
 1658print_char('#', Out) :- !, write(Out, '\\#').
 1659print_char('%', Out) :- !, write(Out, '\\%').
 1660print_char('~', Out) :- !, write(Out, '\\Stilde{}').
 1661print_char('\\',Out) :- !, write(Out, '\\bsl{}').
 1662print_char('^', Out) :- !, write(Out, '\\Shat{}').
 1663print_char('|', Out) :- !, write(Out, '\\Sbar{}').
 1664print_char(C,   Out) :- decompose_char(C, Out), !.
 1665print_char(C,   Out) :- put_char(Out, C).
 1666
 1667%!  decompose_char(+Char) is semidet.
 1668%
 1669%   Deal with diacritics.  Relies  on   Unicode  decomposition,  where a
 1670%   character with diacritics becomes the plain character, followed by a
 1671%   composing diacritics mark.
 1672
 1673:- if(exists_source(library(unicode))). 1674:- use_module(library(unicode)). 1675decompose_char(Char, Out) :-
 1676    char_code(Char, Code),
 1677    Code > 128,
 1678    unicode_map(Char, Decomposed, [decompose]),
 1679    atom_codes(Decomposed, [C,D]),
 1680    diacritic_cmd(D, Cmd),
 1681    format(Out, '\\~w~c', [Cmd, C]).
 1682:- else. 1683decompose_char(_,_) :-
 1684    fail.
 1685:- endif. 1686
 1687diacritic_cmd(768, '`').
 1688diacritic_cmd(769, '\'').
 1689diacritic_cmd(770, '~').
 1690diacritic_cmd(771, '=').
 1691diacritic_cmd(774, 'v').
 1692diacritic_cmd(775, '.').
 1693diacritic_cmd(776, '"').
 1694diacritic_cmd(785, 'u').
 1695diacritic_cmd(807, 'c').
 1696diacritic_cmd(808, 'k').
 1697
 1698%!  identifier(+Atom) is semidet.
 1699%
 1700%   True if Atom is (lower, alnum*).
 1701
 1702identifier(Atom) :-
 1703    atom_chars(Atom, [C0|Chars]),
 1704    char_type(C0, lower),
 1705    all_chartype(Chars, alnum).
 1706
 1707all_chartype([], _).
 1708all_chartype([H|T], Type) :-
 1709    char_type(H, Type),
 1710    all_chartype(T, Type).
 1711
 1712
 1713                 /*******************************
 1714                 *    LATEX SPECIAL SEQUENCES   *
 1715                 *******************************/
 1716
 1717%!  urldef_name(?String, ?DefName)
 1718%
 1719%   True if \DefName is  a  urldef   for  String.  UrlDefs are LaTeX
 1720%   sequences that can be used to  represent strings with symbols in
 1721%   fragile environments. Whenever a word can   be  expressed with a
 1722%   urldef, we will  do  this  to   enhance  the  robustness  of the
 1723%   generated LaTeX code.
 1724
 1725:- dynamic
 1726    urldef_name/2,
 1727    urlchar/1,                      % true if C appears in ine of them
 1728    urldefs_loaded/1. 1729
 1730%!  load_urldefs.
 1731%!  load_urldefs(+File)
 1732%
 1733%   Load   =|\urldef|=   definitions   from    File   and   populate
 1734%   urldef_name/2. See =|pldoc.sty|= for details.
 1735
 1736load_urldefs :-
 1737    urldefs_loaded(_),
 1738    !.
 1739load_urldefs :-
 1740    absolute_file_name(library('pldoc/pldoc.sty'), File,
 1741                       [ access(read) ]),
 1742    load_urldefs(File).
 1743
 1744load_urldefs(File) :-
 1745    urldefs_loaded(File),
 1746    !.
 1747load_urldefs(File) :-
 1748    open(File, read, In),
 1749    call_cleanup((   read_line_to_codes(In, L0),
 1750                     process_urldefs(L0, In)),
 1751                 close(In)),
 1752    assert(urldefs_loaded(File)).
 1753
 1754process_urldefs(end_of_file, _) :- !.
 1755process_urldefs(Line, In) :-
 1756    (   phrase(urldef(Name, String), Line)
 1757    ->  assert(urldef_name(String, Name)),
 1758        assert_chars(String)
 1759    ;   true
 1760    ),
 1761    read_line_to_codes(In, L2),
 1762    process_urldefs(L2, In).
 1763
 1764assert_chars(String) :-
 1765    atom_chars(String, Chars),
 1766    (   member(C, Chars),
 1767        \+ urlchar(C),
 1768        assert(urlchar(C)),
 1769        fail
 1770    ;   true
 1771    ).
 1772
 1773urldef(Name, String) -->
 1774    "\\urldef{\\", string(NameS), "}\\satom{", string(StringS), "}",
 1775    ws,
 1776    (   "%"
 1777    ->  string(_)
 1778    ;   []
 1779    ),
 1780    eol,
 1781    !,
 1782    { atom_codes(Name, NameS),
 1783      atom_codes(String, StringS)
 1784    }.
 1785
 1786ws --> [C], { C =< 32 }, !, ws.
 1787ws --> [].
 1788
 1789string([]) --> [].
 1790string([H|T]) --> [H], string(T).
 1791
 1792eol([],[]).
 1793
 1794
 1795                 /*******************************
 1796                 *         HEADER/FOOTER        *
 1797                 *******************************/
 1798
 1799latex_header(Out, Options) :-
 1800    (   option(stand_alone(true), Options, true)
 1801    ->  forall(header(Line), format(Out, '~w~n', [Line]))
 1802    ;   true
 1803    ),
 1804    forall(generated(Line), format(Out, '~w~n', [Line])).
 1805
 1806latex_footer(Out, Options) :-
 1807    (   option(stand_alone(true), Options, true)
 1808    ->  forall(footer(Line), format(Out, '~w~n', [Line]))
 1809    ;   true
 1810    ).
 1811
 1812header('\\documentclass[11pt]{article}').
 1813header('\\usepackage{times}').
 1814header('\\usepackage{pldoc}').
 1815header('\\sloppy').
 1816header('\\makeindex').
 1817header('').
 1818header('\\begin{document}').
 1819
 1820footer('').
 1821footer('\\printindex').
 1822footer('\\end{document}').
 1823
 1824generated('% This LaTeX document was generated using the LaTeX backend of PlDoc,').
 1825generated('% The SWI-Prolog documentation system').
 1826generated('').
 1827
 1828
 1829		 /*******************************
 1830		 *            MESSAGES		*
 1831		 *******************************/
 1832
 1833:- multifile
 1834    prolog:message//1. 1835
 1836prolog:message(pldoc(no_summary_for(Obj))) -->
 1837    [ 'No summary documentation for ~p'-[Obj] ]