| Home | Libraries | People | FAQ | More

## Class template basic_option

boost::program_options::basic_option

## Synopsis

    // In header: <boost/program_options/option.hpp>

    template<typename charT>
    class basic_option {
    public:
      // construct/copy/destruct
      basic_option();
      basic_option(const std::string &, const std::vector< std::string > &);

      // public data members
      std::string string_key;
      int position_key;
      std::vector< std::basic_string< charT > > value;
      std::vector< std::basic_string< charT > > original_tokens;
      bool unregistered;
      bool case_insensitive;
    };

## Description

Option found in input source. Contains a key and a value. The key, in turn, can be a string (name of an option), or an integer (position in input source) <ndash></ndash> in case no name is specified. The latter is only possible for command line. The template parameter specifies the type of char used for storing the option's value.

### `basic_option` public construct/copy/destruct

1.     basic_option();

2.     basic_option(const std::string & xstring_key,
                    const std::vector< std::string > & xvalue);

### `basic_option` public public data members

1.     std::string string_key;

   String key of this option. Intentionally independent of the template parameter.

2.     int position_key;

   Position key of this option. All options without an explicit name are sequentially numbered starting from 0. If an option has explicit name, 'position_key' is equal to -1. It is possible that both position_key and string_key is specified, in case name is implicitly added.

3.     std::vector< std::basic_string< charT > > value;

   Option's value

4.     std::vector< std::basic_string< charT > > original_tokens;

   The original unchanged tokens this option was created from.

5.     bool unregistered;

   True if option was not recognized. In that case, 'string_key' and 'value' are results of purely syntactic parsing of source. The original tokens can be recovered from the "original_tokens" member.

6.     bool case_insensitive;

   True if string_key has to be handled case insensitive.