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    1/*  Part of SWI-Prolog
    2
    3    Author:        Marcus Uneson
    4    E-mail:        marcus.uneson@ling.lu.se
    5    WWW:           http://person.sol.lu.se/MarcusUneson/
    6    Copyright (c)  2011-2015, Marcus Uneson
    7    All rights reserved.
    8
    9    Redistribution and use in source and binary forms, with or without
   10    modification, are permitted provided that the following conditions
   11    are met:
   12
   13    1. Redistributions of source code must retain the above copyright
   14       notice, this list of conditions and the following disclaimer.
   15
   16    2. Redistributions in binary form must reproduce the above copyright
   17       notice, this list of conditions and the following disclaimer in
   18       the documentation and/or other materials provided with the
   19       distribution.
   20
   21    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   22    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   23    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   24    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   25    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   26    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   27    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   28    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   29    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   31    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   32    POSSIBILITY OF SUCH DAMAGE.
   33*/
   34
   35:- module(optparse,
   36    [  opt_parse/5,     %+OptsSpec, +CLArgs, -Opts, -PositionalArgs,-ParseOptions
   37       opt_parse/4,     %+OptsSpec, +CLArgs, -Opts, -PositionalArgs,
   38       opt_arguments/3, %+OptsSpec, -Opts, -PositionalArgs
   39       opt_help/2       %+OptsSpec, -Help
   40    ]).   41
   42:- autoload(library(apply),[maplist/3]).   43:- autoload(library(debug),[assertion/1]).   44:- autoload(library(error),[must_be/2]).   45:- autoload(library(lists),[member/2,max_list/2,reverse/2,append/3]).   46:- autoload(library(option),[merge_options/3,option/3]).   47
   48
   49:- set_prolog_flag(double_quotes, codes).   50%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% EXPORTS
   51
   52/** <module> command line parsing
   53
   54This  module  helps  in  building  a    command-line   interface  to  an
   55application. In particular, it provides functions   that  take an option
   56specification and a list of atoms, probably  given to the program on the
   57command line, and  return  a  parsed   representation  (a  list  of  the
   58customary Key(Val) by default; or optionally,   a list of Func(Key, Val)
   59terms in the style of current_prolog_flag/2).   It can also synthesize a
   60simple help text from the options specification.
   61
   62The terminology in the following  is   partly  borrowed from python, see
   63http://docs.python.org/library/optparse.html#terminology . Very briefly,
   64_arguments_ is what you provide on the command line and for many prologs
   65show up as a  list  of   atoms  =|Args|=  in =|current_prolog_flag(argv,
   66Args)|=. For a typical prolog incantation, they can be divided into
   67
   68    * _|runtime arguments|_, which controls the prolog runtime;
   69    conventionally, they are ended by '--';
   70    * _options_, which are key-value pairs (with a boolean value
   71    possibly implicit) intended to control your program in one way
   72    or another; and
   73    * _|positional arguments|_, which is what remains after
   74    all runtime arguments and options have been removed (with
   75    implicit arguments -- true/false for booleans -- filled in).
   76
   77Positional arguments are in  particular   used  for  mandatory arguments
   78without which your program  won't  work  and   for  which  there  are no
   79sensible defaults (e.g,, input file names).  Options, by contrast, offer
   80flexibility by letting  you  change  a   default  setting.  Options  are
   81optional not only by etymology: this library  has no notion of mandatory
   82or required options (see  the  python   docs  for  other rationales than
   83laziness).
   84
   85The command-line arguments enter your program as   a  list of atoms, but
   86the programs perhaps expects booleans, integers,   floats or even prolog
   87terms. You tell the parser so by providing an _|options specification|_.
   88This is just a list of individual   option specifications. One of those,
   89in turn, is a list of ground   prolog terms in the customary Name(Value)
   90format. The following terms are recognized (any others raise error).
   91
   92        * opt(Key)
   93        Key is what the option later will be accessed by, just like for
   94        current_prolog_flag(Key, Value). This term is mandatory (an error is
   95        thrown if missing).
   96
   97        * shortflags(ListOfFlags)
   98        ListOfFlags denotes any single-dashed, single letter args specifying the
   99        current option (=|-s , -K|=, etc). Uppercase letters must be quoted.
  100        Usually ListOfFlags will be a singleton list, but sometimes aliased flags
  101        may be convenient.
  102
  103        * longflags(ListOfFlags)
  104        ListOfFlags denotes any double-dashed arguments specifying
  105        the current option (=|--verbose, --no-debug|=, etc). They are
  106        basically a more readable alternative to short flags, except
  107
  108        1. long flags can be specified as =|--flag value|= or
  109        =|--flag=value|= (but not as =|--flagvalue|=); short flags as
  110        =|-f val|= or =|-fval|= (but not =|-f=val|=)
  111        2. boolean long flags can be specified as =|--bool-flag|=
  112        or =|--bool-flag=true|= or =|--bool-flag true|=; and they can be
  113        negated as =|--no-bool-flag|= or =|--bool-flag=false|= or
  114        =|--bool-flag false|=.
  115
  116        Except that shortflags must be single characters, the
  117        distinction between long and short is in calling convention, not
  118        in namespaces. Thus, if you have shortflags([v]), you can use it
  119        as =|-v2|= or =|-v 2|= or =|--v=2|= or =|--v 2|= (but not
  120        =|-v=2|= or =|--v2|=).
  121
  122        Shortflags and longflags both default to =|[]|=. It can be useful to
  123        have flagless options -- see example below.
  124
  125        * meta(Meta)
  126        Meta is optional and only relevant for the synthesized usage message
  127        and is the name (an atom) of the metasyntactic variable (possibly)
  128        appearing in it together with type and default value (e.g,
  129        =|x:integer=3|=, =|interest:float=0.11|=). It may be useful to
  130        have named variables (=|x|=, =|interest|=) in case you wish to
  131        mention them again in the help text. If not given the =|Meta:|=
  132        part is suppressed -- see example below.
  133
  134        * type(Type)
  135        Type is one of =|boolean, atom, integer, float, term|=.
  136        The corresponding argument will be parsed appropriately. This
  137        term is optional; if not given, defaults to =|term|=.
  138
  139        * default(Default)
  140        Default value. This term is optional; if not given, or if given the
  141        special value '_', an uninstantiated variable is created (and any
  142        type declaration is ignored).
  143
  144        * help(Help)
  145        Help is (usually) an atom of text describing the option in the
  146        help text. This term is optional (but obviously strongly recommended
  147        for all options which have flags).
  148
  149        Long lines are subject to basic word wrapping -- split on white
  150        space, reindent, rejoin. However, you can get more control by
  151        supplying the line breaking yourself: rather than a single line of
  152        text, you can provide a list of lines (as atoms). If you do, they
  153        will be joined with the appropriate indent but otherwise left
  154        untouched (see the option =mode= in the example below).
  155
  156Absence of mandatory option specs or the presence of more than one for a
  157particular option throws an error, as do unknown or incompatible types.
  158
  159As a concrete example from a fictive   application,  suppose we want the
  160following options to be read from the  command line (long flag(s), short
  161flag(s), meta:type=default, help)
  162
  163==
  164--mode                  -m     atom=SCAN       data gathering mode,
  165                                               one of
  166                                                SCAN: do this
  167                                                READ: do that
  168                                                MAKE: make numbers
  169                                                WAIT: do nothing
  170--rebuild-cache         -r     boolean=true    rebuild cache in
  171                                               each iteration
  172--heisenberg-threshold  -t,-h  float=0.1       heisenberg threshold
  173--depths, --iters       -i,-d  K:integer=3     stop after K
  174                                               iterations
  175--distances                    term=[1,2,3,5]  initial prolog term
  176--output-file           -o     FILE:atom=_     write output to FILE
  177--label                 -l     atom=REPORT     report label
  178--verbosity             -v     V:integer=2     verbosity level,
  179                                               1 <= V <= 3
  180==
  181
  182We may also have some configuration  parameters which we currently think
  183not   needs   to   be   controlled   from    the   command   line,   say
  184path('/some/file/path').
  185
  186This interface is  described  by   the  following  options specification
  187(order between the specifications of a particular option is irrelevant).
  188
  189==
  190ExampleOptsSpec =
  191    [ [opt(mode    ), type(atom), default('SCAN'),
  192        shortflags([m]),   longflags(['mode'] ),
  193        help([ 'data gathering mode, one of'
  194             , '  SCAN: do this'
  195             , '  READ: do that'
  196             , '  MAKE: fabricate some numbers'
  197             , '  WAIT: don''t do anything'])]
  198
  199    , [opt(cache), type(boolean), default(true),
  200        shortflags([r]),   longflags(['rebuild-cache']),
  201        help('rebuild cache in each iteration')]
  202
  203    , [opt(threshold), type(float), default(0.1),
  204        shortflags([t,h]),  longflags(['heisenberg-threshold']),
  205        help('heisenberg threshold')]
  206
  207    , [opt(depth), meta('K'), type(integer), default(3),
  208        shortflags([i,d]),longflags([depths,iters]),
  209        help('stop after K iterations')]
  210
  211    , [opt(distances), default([1,2,3,5]),
  212        longflags([distances]),
  213        help('initial prolog term')]
  214
  215    , [opt(outfile), meta('FILE'), type(atom),
  216        shortflags([o]),  longflags(['output-file']),
  217        help('write output to FILE')]
  218
  219    , [opt(label), type(atom), default('REPORT'),
  220        shortflags([l]), longflags([label]),
  221        help('report label')]
  222
  223    , [opt(verbose),  meta('V'), type(integer), default(2),
  224        shortflags([v]),  longflags([verbosity]),
  225        help('verbosity level, 1 <= V <= 3')]
  226
  227    , [opt(path), default('/some/file/path/')]
  228    ].
  229==
  230
  231The  help  text  above  was   accessed  by  =|opt_help(ExamplesOptsSpec,
  232HelpText)|=. The options appear in the same order as in the OptsSpec.
  233
  234Given  =|ExampleOptsSpec|=,  a  command   line  (somewhat  syntactically
  235inconsistent, in order to demonstrate different calling conventions) may
  236look as follows
  237
  238==
  239ExampleArgs = [ '-d5'
  240              , '--heisenberg-threshold', '0.14'
  241              , '--distances=[1,1,2,3,5,8]'
  242              , '--iters', '7'
  243              , '-ooutput.txt'
  244              , '--rebuild-cache', 'true'
  245              , 'input.txt'
  246              , '--verbosity=2'
  247              ].
  248==
  249
  250opt_parse(ExampleOptsSpec, ExampleArgs, Opts, PositionalArgs) would then
  251succeed with
  252
  253==
  254Opts =    [ mode('SCAN')
  255          , label('REPORT')
  256          , path('/some/file/path')
  257          , threshold(0.14)
  258          , distances([1,1,2,3,5,8])
  259          , depth(7)
  260          , outfile('output.txt')
  261          , cache(true)
  262          , verbose(2)
  263          ],
  264PositionalArgs = ['input.txt'].
  265==
  266
  267Note that path('/some/file/path') showing up in Opts has a default value
  268(of the implicit type 'term'), but   no corresponding flags in OptsSpec.
  269Thus it can't be set from the  command   line.  The rest of your program
  270doesn't need to know that, of course.   This  provides an alternative to
  271the common practice of asserting  such   hard-coded  parameters  under a
  272single predicate (for instance   setting(path, '/some/file/path')), with
  273the advantage that you  may  seamlessly   upgrade  them  to command-line
  274options, should you  one  day  find  this   a  good  idea.  Just  add an
  275appropriate flag or two and a line  of help text. Similarly, suppressing
  276an option in a cluttered interface amounts to commenting out the flags.
  277
  278opt_parse/5 allows more control through an   additional argument list as
  279shown in the example below.
  280
  281==
  282?- opt_parse(ExampleOptsSpec, ExampleArgs,  Opts, PositionalArgs,
  283             [ output_functor(appl_config)
  284             ]).
  285
  286Opts =    [ appl_config(verbose, 2),
  287          , appl_config(label, 'REPORT')
  288          ...
  289          ]
  290==
  291
  292This representation may be preferable  with the empty-flag configuration
  293parameter style above (perhaps with asserting appl_config/2).
  294
  295## Notes and tips {#optparse-notes}
  296
  297    * In the example we were mostly explicit about the types. Since the
  298    default is =|term|=, which subsumes =|integer, float, atom|=, it
  299    may be possible to get away cheaper (e.g., by only giving booleans).
  300    However, it is recommended practice to always specify types:
  301    parsing becomes more reliable and error messages will be easier to interpret.
  302
  303
  304    * Note that =|-sbar|= is taken to mean =|-s bar|=, not =|-s -b -a -r|=,
  305    that is, there is no clustering of flags.
  306
  307    * =|-s=foo|= is disallowed. The rationale is that although some
  308    command-line parsers will silently interpret this as =|-s =foo|=, this is very
  309    seldom what you want. To have an option argument start with '=' (very
  310    un-recommended), say so explicitly.
  311
  312    * The example specifies the option =|depth|= twice: once as
  313    =|-d5|= and once as =|--iters 7|=. The default when encountering duplicated
  314    flags is to =|keeplast|= (this behaviour can be controlled, by ParseOption
  315    duplicated_flags).
  316
  317    * The order of the options returned by the parsing functions is the same as
  318    given on the command
  319    line, with non-overridden defaults prepended and duplicates removed
  320    as in previous item. You should not rely on this, however.
  321
  322    * Unknown flags (not appearing in OptsSpec) will throw errors. This
  323    is usually a Good Thing. Sometimes, however, you may wish to pass
  324    along flags to an external program (say, one called by shell/2), and
  325    it means duplicated effort and a maintenance headache to have to
  326    specify all possible flags for the external program explicitly (if
  327    it even can be done). On the other hand, simply taking all unknown
  328    flags as valid makes error checking much less efficient and
  329    identification of positional arguments uncertain. A better solution
  330    is to collect all arguments intended for passing along to an
  331    indirectly called program as a single argument, probably as an atom
  332    (if you don't need to inspect them first) or as a prolog term (if
  333    you do).
  334
  335@author Marcus Uneson
  336@version 0.20 (2011-04-27)
  337@tbd: validation? e.g, numbers; file path existence; one-out-of-a-set-of-atoms
  338*/
  339
  340:- predicate_options(opt_parse/5, 5,
  341                     [ allow_empty_flag_spec(boolean),
  342                       duplicated_flags(oneof([keepfirst,keeplast,keepall])),
  343                       output_functor(atom),
  344                       suppress_empty_meta(boolean)
  345                     ]).  346
  347:- multifile
  348    error:has_type/2,
  349    parse_type/3.  350
  351%%   opt_arguments(+OptsSpec, -Opts, -PositionalArgs) is det
  352%
  353%    Extract  commandline  options   according    to   a  specification.
  354%    Convenience predicate, assuming that command-line  arguments can be
  355%    accessed by current_prolog_flag/2 (as  in   swi-prolog).  For other
  356%    access mechanisms and/or more control, get   the args and pass them
  357%    as a list of atoms to opt_parse/4 or opt_parse/5 instead.
  358%
  359%    Opts is a list of parsed  options   in  the form Key(Value). Dashed
  360%    args not in OptsSpec are not permitted   and  will raise error (see
  361%    tip on how to  pass  unknown   flags  in  the  module description).
  362%    PositionalArgs are the remaining non-dashed   args  after each flag
  363%    has taken its argument (filling in =true= or =false= for booleans).
  364%    There are no restrictions on non-dashed   arguments and they may go
  365%    anywhere (although it is  good  practice   to  put  them last). Any
  366%    leading arguments for the runtime (up   to  and including '--') are
  367%    discarded.
  368
  369opt_arguments(OptsSpec, Opts, PositionalArgs) :-
  370    current_prolog_flag(argv, Argv),
  371    opt_parse(OptsSpec, Argv, Opts, PositionalArgs).
  372
  373%%   opt_parse(+OptsSpec, +ApplArgs, -Opts, -PositionalArgs) is det
  374%
  375%    Equivalent to opt_parse(OptsSpec, ApplArgs, Opts, PositionalArgs, []).
  376
  377
  378opt_parse(OptsSpec, ApplArgs, Opts, PositionalArgs) :-
  379    opt_parse(OptsSpec, ApplArgs, Opts, PositionalArgs, []).
  380
  381%%   opt_parse(+OptsSpec, +ApplArgs, -Opts, -PositionalArgs, +ParseOptions) is det
  382%
  383%    Parse the arguments Args (as list  of atoms) according to OptsSpec.
  384%    Any runtime arguments (typically terminated by '--') are assumed to
  385%    be removed already.
  386%
  387%    Opts is a list of parsed options   in the form Key(Value), or (with
  388%    the option functor(Func)  given)  in   the  form  Func(Key, Value).
  389%    Dashed args not in OptsSpec are not  permitted and will raise error
  390%    (see tip on how to pass unknown   flags in the module description).
  391%    PositionalArgs are the remaining non-dashed   args  after each flag
  392%    has taken its argument (filling in =true= or =false= for booleans).
  393%    There are no restrictions on non-dashed   arguments and they may go
  394%    anywhere  (although  it  is  good  practice   to  put  them  last).
  395%    ParseOptions are
  396%
  397%    * output_functor(Func)
  398%      Set the functor Func of the returned options Func(Key,Value).
  399%      Default is the special value 'OPTION' (upper-case), which makes
  400%      the returned options have form Key(Value).
  401%
  402%    * duplicated_flags(Keep)
  403%      Controls how to handle options given more than once on the commad line.
  404%      Keep is one of  =|keepfirst, keeplast, keepall|= with the obvious meaning.
  405%      Default is =|keeplast|=.
  406%
  407%    * allow_empty_flag_spec(Bool)
  408%      If true (default), a flag specification is not required (it is allowed
  409%      that both shortflags and longflags be either [] or absent).
  410%      Flagless options cannot be manipulated from the command line
  411%      and will not show up in the generated help. This is useful when you
  412%      have (also) general configuration parameters in
  413%      your OptsSpec, especially if you think they one day might need to be
  414%      controlled externally. See example in the module overview.
  415%      allow_empty_flag_spec(false) gives the more customary behaviour of
  416%      raising error on empty flags.
  417
  418
  419opt_parse(OptsSpec, ApplArgs, Opts, PositionalArgs, ParseOptions) :-
  420    opt_parse_(OptsSpec, ApplArgs, Opts, PositionalArgs, ParseOptions).
  421
  422
  423%%   opt_help(+OptsSpec, -Help:atom) is det
  424%
  425%    True when Help is a help string synthesized from OptsSpec.
  426
  427opt_help(OptsSpec, Help) :-
  428    opt_help(OptsSpec, Help, []).
  429
  430% semi-arbitrary default format settings go here;
  431% if someone needs more control one day, opt_help/3 could be exported
  432opt_help(OptsSpec, Help, HelpOptions0) :-
  433    Defaults = [ line_width(80)
  434               , min_help_width(40)
  435               , break_long_flags(false)
  436               , suppress_empty_meta(true)
  437               ],
  438    merge_options(HelpOptions0, Defaults, HelpOptions),
  439    opt_help_(OptsSpec, Help, HelpOptions).
  440
  441
  442%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% OPT_PARSE
  443
  444opt_parse_(OptsSpec0, Args0, Opts, PositionalArgs, ParseOptions) :-
  445    must_be(list(atom), Args0),
  446
  447    check_opts_spec(OptsSpec0, ParseOptions, OptsSpec),
  448
  449    maplist(atom_codes, Args0, Args1),
  450    parse_options(OptsSpec, Args1, Args2, PositionalArgs),
  451    add_default_opts(OptsSpec, Args2, Args3),
  452
  453    option(duplicated_flags(Keep), ParseOptions, keeplast),
  454    remove_duplicates(Keep, Args3, Args4),
  455
  456    option(output_functor(Func), ParseOptions, 'OPTION'),
  457    refunctor_opts(Func, Args4, Opts). %}}}
  458
  459
  460
  461%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% MAKE HELP
  462opt_help_(OptsSpec0, Help, HelpOptions) :-
  463    check_opts_spec(OptsSpec0, HelpOptions, OptsSpec1),
  464    include_in_help(OptsSpec1, OptsSpec2),
  465    format_help_fields(OptsSpec2, OptsSpec3),
  466    col_widths(OptsSpec3, [shortflags, metatypedef], CWs),
  467    long_flag_col_width(OptsSpec3, LongestFlagWidth),
  468    maplist(format_opt(LongestFlagWidth, CWs, HelpOptions), OptsSpec3, Lines),
  469    atomic_list_concat(Lines, Help).
  470
  471include_in_help([], []).
  472include_in_help([OptSpec|OptsSpec], Result) :-
  473    (  flags(OptSpec, [_|_])
  474    -> Result = [OptSpec|Rest]
  475    ;  Result = Rest
  476    ),
  477    include_in_help(OptsSpec, Rest).
  478
  479format_help_fields(OptsSpec0, OptsSpec) :-
  480    maplist(embellish_flag(short), OptsSpec0, OptsSpec1),
  481    maplist(embellish_flag(long), OptsSpec1, OptsSpec2),
  482    maplist(merge_meta_type_def, OptsSpec2, OptsSpec).
  483
  484merge_meta_type_def(OptSpecIn, [metatypedef(MTD)|OptSpecIn]) :-
  485    memberchk(meta(Meta), OptSpecIn),
  486    memberchk(type(Type), OptSpecIn),
  487    memberchk(default(Def), OptSpecIn),
  488    atom_length(Meta, N),
  489    (  N > 0
  490    -> format(atom(MTD), '~w:~w=~w', [Meta, Type, Def])
  491    ;  format(atom(MTD), '~w=~w', [Type, Def])
  492    ).
  493embellish_flag(short, OptSpecIn, OptSpecOut) :-
  494    memberchk(shortflags(FlagsIn), OptSpecIn),
  495    maplist(atom_concat('-'), FlagsIn, FlagsOut0),
  496    atomic_list_concat(FlagsOut0, ',',  FlagsOut),
  497    merge_options([shortflags(FlagsOut)], OptSpecIn, OptSpecOut).
  498embellish_flag(long, OptSpecIn, OptSpecOut) :-
  499    memberchk(longflags(FlagsIn), OptSpecIn),
  500    maplist(atom_concat('--'), FlagsIn, FlagsOut),
  501    merge_options([longflags(FlagsOut)], OptSpecIn, OptSpecOut).
  502
  503col_widths(OptsSpec, Functors, ColWidths) :-
  504    maplist(col_width(OptsSpec), Functors, ColWidths).
  505col_width(OptsSpec, Functor, ColWidth) :-
  506    findall(N,
  507            ( member(OptSpec, OptsSpec),
  508              M =.. [Functor, Arg],
  509              member(M, OptSpec),
  510              format(atom(Atom), '~w', [Arg]),
  511              atom_length(Atom, N0),
  512              N is N0 + 2     %separate cols with two spaces
  513            ),
  514            Ns),
  515    max_list([0|Ns], ColWidth).
  516
  517long_flag_col_width(OptsSpec, ColWidth) :-
  518    findall(FlagLength,
  519           ( member(OptSpec, OptsSpec),
  520             memberchk(longflags(LFlags), OptSpec),
  521             member(LFlag, LFlags),
  522             atom_length(LFlag, FlagLength)
  523             ),
  524            FlagLengths),
  525    max_list([0|FlagLengths], ColWidth).
  526
  527
  528format_opt(LongestFlagWidth, [SFlagsCW, MTDCW], HelpOptions, Opt, Line) :-
  529    memberchk(shortflags(SFlags), Opt),
  530
  531    memberchk(longflags(LFlags0), Opt),
  532    group_length(LongestFlagWidth, LFlags0, LFlags1),
  533    LFlagsCW is LongestFlagWidth + 2, %separate with comma and space
  534    option(break_long_flags(BLF), HelpOptions, true),
  535    (  BLF
  536    -> maplist(atomic_list_concat_(',\n'), LFlags1, LFlags2)
  537    ;  maplist(atomic_list_concat_(', '), LFlags1, LFlags2)
  538    ),
  539    atomic_list_concat(LFlags2, ',\n', LFlags),
  540
  541    memberchk(metatypedef(MetaTypeDef), Opt),
  542
  543    memberchk(help(Help), Opt),
  544    HelpIndent is LFlagsCW + SFlagsCW + MTDCW + 2,
  545    option(line_width(LW), HelpOptions, 80),
  546    option(min_help_width(MHW), HelpOptions, 40),
  547    HelpWidth is max(MHW, LW - HelpIndent),
  548    (  atom(Help)
  549    -> line_breaks(Help, HelpWidth, HelpIndent, BrokenHelp)
  550    ;  assertion(is_list_of_atoms(Help))
  551    -> indent_lines(Help, HelpIndent, BrokenHelp)
  552    ),
  553    format(atom(Line), '~w~t~*+~w~t~*+~w~t~*+~w~n',
  554      [LFlags, LFlagsCW, SFlags, SFlagsCW, MetaTypeDef, MTDCW, BrokenHelp]).
  555
  556
  557line_breaks(TextLine, LineLength, Indent, TextLines) :-
  558    atomic_list_concat(Words, ' ', TextLine),
  559    group_length(LineLength, Words, Groups0),
  560    maplist(atomic_list_concat_(' '), Groups0, Groups),
  561    indent_lines(Groups, Indent, TextLines).
  562
  563indent_lines(Lines, Indent, TextLines) :-
  564    format(atom(Separator), '~n~*|', [Indent]),
  565    atomic_list_concat(Lines, Separator, TextLines).
  566
  567atomic_list_concat_(Separator, List, Atom) :-
  568    atomic_list_concat(List, Separator, Atom).
  569
  570%group_length(10,
  571%             [here, are, some, words, you, see],
  572%             [[here are], [some words], [you see]]) %each group >= 10F
  573group_length(LineLength, Words, Groups) :-
  574    group_length_(Words, LineLength, LineLength, [], [], Groups).
  575
  576group_length_([], _, _, ThisLine, GroupsAcc, Groups) :-
  577    maplist(reverse, [ThisLine|GroupsAcc], GroupsAcc1),
  578    reverse(GroupsAcc1, Groups).
  579group_length_([Word|Words], LineLength, Remains, ThisLine, Groups, GroupsAcc) :-
  580    atom_length(Word, K),
  581    (  (Remains >= K; ThisLine = [])  %Word fits on ThisLine, or too long too fit
  582    -> Remains1 is Remains - K - 1,  %even on a new line
  583     group_length_(Words, LineLength, Remains1, [Word|ThisLine], Groups, GroupsAcc)
  584
  585                                     %Word doesn't fit on ThisLine (non-empty)
  586    ;  group_length_([Word|Words], LineLength, LineLength, [], [ThisLine|Groups], GroupsAcc)
  587    ).
  588
  589
  590%}}}
  591
  592
  593%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% OPTSSPEC DEFAULTS
  594
  595
  596add_default_defaults(OptsSpec0, OptsSpec, Options) :-
  597    option(suppress_empty_meta(SEM), Options, true),
  598    maplist(default_defaults(SEM), OptsSpec0, OptsSpec).
  599
  600default_defaults(SuppressEmptyMeta, OptSpec0, OptSpec) :-
  601    (  SuppressEmptyMeta
  602    -> Meta = ''
  603    ;  memberchk(type(Type), OptSpec0)
  604    -> meta_placeholder(Type, Meta)
  605    ;  Meta = 'T'
  606    ),
  607
  608    Defaults = [ help('')
  609             , type(term)
  610             , shortflags([])
  611             , longflags([])
  612             , default('_')
  613             , meta(Meta)
  614             ],
  615    merge_options(OptSpec0, Defaults, OptSpec).
  616    %merge_options(+New, +Old, -Merged)
  617
  618
  619meta_placeholder(boolean, 'B').
  620meta_placeholder(atom, 'A').
  621meta_placeholder(float, 'F').
  622meta_placeholder(integer, 'I').
  623meta_placeholder(term, 'T').
  624
  625
  626
  627%}}}
  628
  629
  630%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% OPTSSPEC VALIDATION
  631
  632%this is a bit paranoid, but OTOH efficiency is no issue
  633check_opts_spec(OptsSpec0, Options, OptsSpec) :-
  634    validate_opts_spec(OptsSpec0, Options),
  635    add_default_defaults(OptsSpec0, OptsSpec, Options),
  636    validate_opts_spec(OptsSpec, Options).
  637
  638validate_opts_spec(OptsSpec, ParseOptions) :-
  639    \+ invalidate_opts_spec(OptsSpec, ParseOptions).
  640
  641invalidate_opts_spec(OptsSpec, _ParseOptions) :-
  642    %invalid if not ground -- must go first for \+ to be sound
  643    ( \+ ground(OptsSpec)
  644    -> throw(error(instantiation_error,
  645                   context(validate_opts_spec/1, 'option spec must be ground')))
  646
  647    %invalid if conflicting flags
  648    ; ( member(O1, OptsSpec), flags(O1, Flags1), member(F, Flags1),
  649        member(O2, OptsSpec), flags(O2, Flags2), member(F, Flags2),
  650        O1 \= O2)
  651    -> throw(error(domain_error(unique_atom, F),
  652                   context(validate_opts_spec/1, 'ambiguous flag')))
  653
  654    %invalid if unknown opt spec
  655    ; ( member(OptSpec, OptsSpec),
  656        member(Spec, OptSpec),
  657        functor(Spec, F, _),
  658        \+ member(F, [opt, shortflags, longflags, type, help, default, meta]) )
  659    ->  throw(error(domain_error(opt_spec, F),
  660                   context(validate_opts_spec/1, 'unknown opt spec')))
  661
  662    %invalid if mandatory option spec opt(ID) is not unique in the entire Spec
  663    ; ( member(O1, OptsSpec), member(opt(Name), O1),
  664        member(O2, OptsSpec), member(opt(Name), O2),
  665        O1 \= O2)
  666    -> throw(error(domain_error(unique_atom, Name),
  667                   context(validate_opts_spec/1, 'ambiguous id')))
  668    ).
  669
  670invalidate_opts_spec(OptsSpec, _ParseOptions) :-
  671    member(OptSpec, OptsSpec),
  672    \+ member(opt(_Name), OptSpec),
  673    %invalid if mandatory option spec opt(ID) is absent
  674    throw(error(domain_error(unique_atom, OptSpec),
  675                context(validate_opts_spec/1, 'opt(id) missing'))).
  676
  677invalidate_opts_spec(OptsSpec, ParseOptions) :-
  678    member(OptSpec, OptsSpec), %if we got here, OptSpec has a single unique Name
  679    member(opt(Name), OptSpec),
  680
  681    option(allow_empty_flag_spec(AllowEmpty), ParseOptions, true),
  682
  683    %invalid if allow_empty_flag_spec(false) and no flag is given
  684    ( (\+ AllowEmpty, \+ flags(OptSpec, [_|_]))
  685    -> format(atom(Msg), 'no flag specified for option ''~w''', [Name]),
  686       throw(error(domain_error(unique_atom, _),
  687                context(validate_opts_spec/1, Msg)))
  688
  689    %invalid if any short flag is not actually single-letter
  690    ; ( memberchk(shortflags(Flags), OptSpec),
  691        member(F, Flags),
  692        atom_length(F, L),
  693        L > 1)
  694    ->  format(atom(Msg), 'option ''~w'': flag too long to be short', [Name]),
  695        throw(error(domain_error(short_flag, F),
  696                context(validate_opts_spec/1, Msg)))
  697
  698    %invalid if any option spec is given more than once
  699    ; duplicate_optspec(OptSpec,
  700      [type,opt,default,help,shortflags,longflags,meta])
  701    ->  format(atom(Msg), 'duplicate spec in option ''~w''', [Name]),
  702        throw(error(domain_error(unique_functor, _),
  703                context(validate_opts_spec/1, Msg)))
  704
  705    %invalid if unknown type
  706    ;   (   memberchk(type(Type), OptSpec),
  707            Type \== term,
  708            \+ clause(error:has_type(Type,_), _)
  709        )
  710    ->  format(atom(Msg), 'unknown type ''~w'' in option ''~w''', [Type, Name]),
  711        throw(error(type_error(flag_value, Type),
  712              context(validate_opts_spec/1, Msg)))
  713
  714    %invalid if type does not match default
  715    %note1: reverse logic: we are trying to _in_validate OptSpec
  716
  717    %note2: 'term' approves of any syntactically valid prolog term, since
  718    %if syntactically invalid, OptsSpec wouldn't have parsed
  719
  720    %note3: the special placeholder '_' creates a new variable, so no typecheck
  721    ;    (memberchk(type(Type), OptSpec),
  722          Type \= term,
  723          memberchk(default(Default), OptSpec),
  724          Default \= '_'
  725    ->   \+ must_be(Type, Default))
  726
  727    %invalidation failed, i.e., optspec is OK
  728    ; fail
  729    ).
  730
  731duplicate_optspec(_, []) :- !, fail.
  732duplicate_optspec(OptSpec, [Func|Funcs]) :-
  733    functor(F, Func, 1),
  734    findall(F, member(F, OptSpec), Xs),
  735    (Xs = [_,_|_]
  736    -> true
  737    ; duplicate_optspec(OptSpec, Funcs)
  738    ).
  739
  740
  741%}}}
  742
  743
  744%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% PARSE OPTIONS
  745% NOTE:
  746% -sbar could be interpreted in two ways: as short for -s bar, and
  747% as short ('clustered') for -s -b -a -r. Here, the former interpretation
  748% is chosen.
  749% Cf http://perldoc.perl.org/Getopt/Long.html (no clustering by default)
  750
  751
  752parse_options(OptsSpec, Args0, Options, PosArgs) :-
  753    append(Args0, [""], Args1),
  754    parse_args_(Args1, OptsSpec, Args2),
  755    partition_args_(Args2, Options, PosArgs).
  756
  757%{{{ PARSE ARGS
  758
  759
  760%if arg is boolean flag given as --no-my-arg, expand to my-arg, false, re-call
  761parse_args_([Arg,Arg2|Args], OptsSpec, [opt(KID, false)|Result]) :-
  762    flag_name_long_neg(Dashed, NonDashed, Arg, []),
  763    flag_id_type(OptsSpec, NonDashed, KID, boolean),
  764    !,
  765    parse_args_([Dashed, "false", Arg2|Args], OptsSpec, Result).
  766
  767%if arg is ordinary boolean flag, fill in implicit true if arg absent; re-call
  768parse_args_([Arg,Arg2|Args], OptsSpec, Result) :-
  769    flag_name(K, Arg, []),
  770    flag_id_type(OptsSpec, K, _KID, boolean),
  771    \+ member(Arg2, ["true", "false"]),
  772    !,
  773    parse_args_([Arg, "true", Arg2 | Args], OptsSpec, Result).
  774
  775% separate short or long flag run together with its value and parse
  776parse_args_([Arg|Args], OptsSpec, [opt(KID, Val)|Result]) :-
  777    flag_name_value(Arg1, Arg2, Arg, []),
  778    \+ short_flag_w_equals(Arg1, Arg2),
  779    flag_name(K, Arg1, []),
  780    !,
  781    parse_option(OptsSpec, K, Arg2, opt(KID, Val)),
  782    parse_args_(Args, OptsSpec, Result).
  783
  784%from here, unparsed args have form
  785%  PosArg1,Flag1,Val1,PosArg2,PosArg3,Flag2,Val2, PosArg4...
  786%i.e., positional args may go anywhere except between FlagN and ValueN
  787%(of course, good programming style says they should go last, but it is poor
  788%programming style to assume that)
  789
  790parse_args_([Arg1,Arg2|Args], OptsSpec, [opt(KID, Val)|Result]) :-
  791    flag_name(K, Arg1, []),
  792    !,
  793    parse_option(OptsSpec, K, Arg2, opt(KID, Val)),
  794    parse_args_(Args, OptsSpec, Result).
  795
  796parse_args_([Arg1,Arg2|Args], OptsSpec, [pos(At)|Result]) :-
  797    \+ flag_name(_, Arg1, []),
  798    !,
  799    atom_codes(At, Arg1),
  800    parse_args_([Arg2|Args], OptsSpec, Result).
  801
  802parse_args_([""], _, []) :- !.   %placeholder, but useful for error messages
  803parse_args_([], _, []) :- !.
  804
  805short_flag_w_equals([0'-,_C], [0'=|_]) :-
  806    throw(error(syntax_error('disallowed: <shortflag>=<value>'),_)).
  807
  808
  809
  810flag_id_type(OptsSpec, FlagCodes, ID, Type) :-
  811    atom_codes(Flag, FlagCodes),
  812    member(OptSpec, OptsSpec),
  813    flags(OptSpec, Flags),
  814    member(Flag, Flags),
  815    member(type(Type), OptSpec),
  816    member(opt(ID), OptSpec).
  817
  818%{{{ FLAG DCG
  819
  820%DCG non-terminals:
  821%  flag_name(NonDashed)                  %c, flag-name, x
  822%  flag_name_short(Dashed, NonDashed)    %c, x
  823%  flag_name_long(Dashed, NonDashed)     %flag-name
  824%  flag_name_long_neg(Dashed, NonDashed) %no-flag-name
  825%  flag_value(Val)                       %non-empty string
  826%  flag_value0(Val)                      %any string, also empty
  827%  flag_name_value(Dashed, Val)          %pair of flag_name, flag_value
  828
  829
  830flag_name(NonDashed) --> flag_name_long(_, NonDashed).
  831flag_name(NonDashed) --> flag_name_short(_, NonDashed).
  832flag_name(NonDashed) --> flag_name_long_neg(_, NonDashed).
  833
  834flag_name_long_neg([0'-,0'-|Cs], Cs) --> "--no-", name_long(Cs).
  835flag_name_long([0'-,0'-|Cs], Cs) --> "--", name_long(Cs).
  836flag_name_short([0'-|C], C) --> "-", name_1st(C).
  837
  838flag_value([C|Cs]) --> [C], flag_value0(Cs).
  839flag_value0([]) --> [].
  840flag_value0([C|Cs]) --> [C], flag_value0(Cs).
  841flag_name_value(Dashed, Val) --> flag_name_long(Dashed, _), "=", flag_value0(Val).
  842flag_name_value(Dashed, Val) --> flag_name_short(Dashed, _), flag_value(Val).
  843
  844name_long([C|Cs]) --> name_1st([C]), name_rest(Cs).
  845name_1st([C]) --> [C], {name_1st(C)}.
  846name_rest([]) --> [].
  847name_rest([C|Cs]) --> [C], {name_char(C)}, name_rest(Cs).
  848name_1st(C) :- char_type(C, alpha).
  849name_char(C) :- char_type(C, alpha).
  850name_char( 0'_ ).
  851name_char( 0'- ). %}}}
  852
  853
  854%{{{ PARSE OPTION
  855parse_option(OptsSpec, Arg1, Arg2, opt(KID, Val)) :-
  856    (  flag_id_type(OptsSpec, Arg1, KID, Type)
  857    -> parse_val(Arg1, Type, Arg2, Val)
  858    ;  format(atom(Msg), '~s', [Arg1]),
  859     opt_help(OptsSpec, Help),        %unknown flag: dump usage on stderr
  860     nl(user_error),
  861     write(user_error, Help),
  862     throw(error(domain_error(flag_value, Msg),context(_, 'unknown flag')))
  863    ).
  864
  865
  866parse_val(Opt, Type, Cs, Val) :-
  867    catch(
  868    parse_loc(Type, Cs, Val),
  869    E,
  870    ( format('~nERROR: flag ''~s'': expected atom parsable as ~w, found ''~s'' ~n',
  871                             [Opt,                           Type,        Cs]),
  872      throw(E))
  873    ).
  874
  875%parse_loc(+Type, +ListOfCodes, -Result).
  876parse_loc(Type, _LOC, _) :-
  877    var(Type), !, throw(error(instantiation_error, _)).
  878parse_loc(_Type, LOC, _) :-
  879    var(LOC), !, throw(error(instantiation_error, _)).
  880parse_loc(boolean, Cs, true) :- atom_codes(true, Cs), !.
  881parse_loc(boolean, Cs, false) :- atom_codes(false, Cs), !.
  882parse_loc(atom, Cs, Result) :- atom_codes(Result, Cs), !.
  883parse_loc(integer, Cs, Result) :-
  884    number_codes(Result, Cs),
  885    integer(Result),
  886
  887    !.
  888parse_loc(float, Cs, Result)   :-
  889    number_codes(Result, Cs),
  890    float(Result),
  891
  892    !.
  893parse_loc(term, Cs, Result) :-
  894    atom_codes(A, Cs),
  895    term_to_atom(Result, A),
  896
  897    !.
  898parse_loc(Type, Cs, Result) :-
  899    parse_type(Type, Cs, Result),
  900    !.
  901parse_loc(Type, _Cs, _) :- %could not parse Cs as Type
  902    throw(error(type_error(flag_value, Type), _)),
  903    !. %}}}
  904%}}}
  905
  906%%  parse_type(+Type, +Codes:list(code), -Result) is semidet.
  907%
  908%   Hook to parse option text Codes to an object of type Type.
  909
  910partition_args_([], [], []).
  911partition_args_([opt(K,V)|Rest], [opt(K,V)|RestOpts], RestPos) :-
  912    !,
  913    partition_args_(Rest, RestOpts, RestPos).
  914partition_args_([pos(Arg)|Rest], RestOpts, [Arg|RestPos]) :-
  915    !,
  916    partition_args_(Rest, RestOpts, RestPos).
  917
  918
  919
  920
  921%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ADD DEFAULTS
  922
  923add_default_opts([], Opts, Opts).
  924add_default_opts([OptSpec|OptsSpec], OptsIn, Result) :-
  925    memberchk(opt(OptName), OptSpec),
  926    (  memberchk(opt(OptName, _Val), OptsIn)
  927    -> Result = OptsOut                      %value given on cl, ignore default
  928
  929    ;                                        %value not given on cl:
  930       memberchk(default('_'), OptSpec)      % no default in OptsSpec (or 'VAR'):
  931    -> Result = [opt(OptName, _) | OptsOut]  % create uninstantiated variable
  932    ;
  933       memberchk(default(Def), OptSpec),     % default given in OptsSpec
  934%       memberchk(type(Type), OptSpec),      % already typechecked
  935%       assertion(must_be(Type, Def)),
  936       Result = [opt(OptName, Def) | OptsOut]
  937    ),
  938    add_default_opts(OptsSpec, OptsIn, OptsOut).
  939
  940
  941
  942%}}}
  943
  944
  945%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% REMOVE DUPLICATES
  946remove_duplicates(_, [], []) :- !.
  947remove_duplicates(keeplast, [opt(OptName, Val) | Opts], Result) :-
  948    !,
  949    (  memberchk(opt(OptName, _), Opts)
  950    -> Result = RestOpts
  951    ;  Result = [opt(OptName, Val) | RestOpts]
  952    ),
  953    remove_duplicates(keeplast, Opts, RestOpts).
  954
  955remove_duplicates(keepfirst, OptsIn, OptsOut) :-
  956    !,
  957    reverse(OptsIn, OptsInRev),
  958    remove_duplicates(keeplast, OptsInRev, OptsOutRev),
  959    reverse(OptsOutRev, OptsOut).
  960
  961remove_duplicates(keepall, OptsIn, OptsIn) :- !.
  962remove_duplicates(K, [_|_], _) :-
  963    !,
  964    throw(error(domain_error(keep_flag, K), _)). %}}}
  965
  966
  967%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% REFUNCTOR
  968refunctor_opts(Fnct, OptsIn, OptsOut) :-
  969    maplist(refunctor_opt(Fnct), OptsIn, OptsOut).
  970
  971refunctor_opt('OPTION', opt(OptName, OptVal), Result) :-
  972    !,
  973    Result =.. [OptName, OptVal].
  974
  975refunctor_opt(F, opt(OptName, OptVal), Result) :-
  976    Result =.. [F, OptName, OptVal]. %}}}
  977
  978
  979%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ACCESSORS
  980
  981flags(OptSpec, Flags) :- memberchk(shortflags(Flags), OptSpec).
  982flags(OptSpec, Flags) :- memberchk(longflags(Flags), OptSpec). %}}}
  983
  984%{{{ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% UTILS
  985is_list_of_atoms([]).
  986is_list_of_atoms([X|Xs]) :- atom(X), is_list_of_atoms(Xs).
  987%}}}