// Copyright Vladimir Prus 2004.

// Distributed under the Boost Software License, Version 1.0.

// (See accompanying file LICENSE_1_0.txt

// or copy at http://www.boost.org/LICENSE_1_0.txt)

#ifndef BOOST_CMDLINE_HPP_VP_2004_03_13

#define BOOST_CMDLINE_HPP_VP_2004_03_13

namespace boost { namespace program_options { namespace command_line_style {

    /** Various possible styles of options.

    There are "long" options, which start with "--" and "short",

    which start with either "-" or "/". Both kinds can be allowed or

    disallowed, see allow_long and allow_short. The allowed character

    for short options is also configurable.

    Option's value can be specified in the same token as name

    ("--foo=bar"), or in the next token.

    It's possible to introduce long options by the same character as

    short options, see allow_long_disguise.

    Finally, guessing (specifying only prefix of option) and case

    insensitive processing are supported.

    */

    enum style_t {

        /// Allow "--long_name" style

        allow_long = 1,

        /// Alow "-<single character" style

        allow_short = allow_long << 1,

        /// Allow "-" in short options

        allow_dash_for_short = allow_short << 1,

        /// Allow "/" in short options

        allow_slash_for_short = allow_dash_for_short << 1,

        /** Allow option parameter in the same token

            for long option, like in

            @verbatim

            --foo=10

            @endverbatim

        */

        long_allow_adjacent = allow_slash_for_short << 1,

        /** Allow option parameter in the next token for

            long options. */

        long_allow_next = long_allow_adjacent << 1,

        /** Allow option parameter in the same token for

            short options. */

        short_allow_adjacent = long_allow_next << 1,

        /** Allow option parameter in the next token for

            short options. */

        short_allow_next = short_allow_adjacent << 1,

        /** Allow to merge several short options together,

            so that "-s -k" become "-sk". All of the options

            but last should accept no parameter. For example, if

            "-s" accept a parameter, then "k" will be taken as

            parameter, not another short option. 

            Dos-style short options cannot be sticky.

        */

        allow_sticky = short_allow_next << 1,

        /** Allow abbreviated spellings for long options,

            if they unambiguously identify long option. 

            No long option name should be prefix of other 

            long option name if guessing is in effect.

        */

        allow_guessing = allow_sticky << 1,

        /** Ignore the difference in case for options. 

            @todo Should this apply to long options only?

        */            

        case_insensitive = allow_guessing << 1,

        /** Allow long options with single option starting character,

            e.g <tt>-foo=10</tt>

        */

        allow_long_disguise = case_insensitive << 1,

        /** The more-or-less traditional unix style. */

        unix_style = (allow_short | short_allow_adjacent | short_allow_next

                      | allow_long | long_allow_adjacent | long_allow_next

                      | allow_sticky | allow_guessing 

                      | allow_dash_for_short),

        /** The default style. */

        default_style = unix_style

    };

}}}

#endif