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Class template period_formatter

boost::date_time::period_formatter — Not a facet, but a class used to specify and control period formats.


template<typename CharT, 
typename OutItrT = std::ostreambuf_iterator<CharT, std::char_traits<CharT> > > 
class period_formatter {
// types
typedef std::basic_string< CharT > string_type;
typedef CharT char_type;
typedef std::basic_string< char_type >::const_iterator const_itr_type;
typedef std::vector< std::basic_string< CharT > > collection_type;

// construct/copy/destruct
period_formatter(range_display_options = AS_CLOSED_RANGE, 
const char_type *const = default_period_separator, 
const char_type *const = default_period_start_delimeter, 
const char_type *const = default_period_open_range_end_delimeter, 
const char_type *const = default_period_closed_range_end_delimeter);

// public member functions
OutItrT put_period_separator(OutItrT &) const;
OutItrT put_period_start_delimeter(OutItrT &) const;
OutItrT put_period_end_delimeter(OutItrT &) const;
range_display_options range_option() const;
void range_option(range_display_options) const;
void delimiter_strings(const string_type &, const string_type &, 
const string_type &, const string_type &) ;
template<typename period_type, typename facet_type> 
OutItrT put_period(OutItrT, std::ios_base &, char_type, 
const period_type &, const facet_type &) const;

static const char_type default_period_separator;
static const char_type default_period_start_delimeter;
static const char_type default_period_open_range_end_delimeter;
static const char_type default_period_closed_range_end_delimeter;


Provides settings for the following:

  • period_separator -- default '/'

  • period_open_start_delimeter -- default '['

  • period_open_range_end_delimeter -- default ')'

  • period_closed_range_end_delimeter -- default ']'

  • display_as_open_range, display_as_closed_range -- default closed_range

Thus the default formatting for a period is as follows:


So for a typical date_period this would be


where the date formatting is controlled by the date facet

period_formatter construct/copy/destruct

  1. period_formatter(range_display_options range_option = AS_CLOSED_RANGE, 
    const char_type *const period_separator = default_period_separator, 
    const char_type *const period_start_delimeter = default_period_start_delimeter, 
    const char_type *const period_open_range_end_delimeter = default_period_open_range_end_delimeter, 
    const char_type *const period_closed_range_end_delimeter = default_period_closed_range_end_delimeter);

period_formatter public member functions

  1. OutItrT put_period_separator(OutItrT & oitr) const;
  2. OutItrT put_period_start_delimeter(OutItrT & oitr) const;
  3. OutItrT put_period_end_delimeter(OutItrT & oitr) const;
  4. range_display_options range_option() const;
  5. void range_option(range_display_options option) const;
  6. void delimiter_strings(const string_type & separator, 
    const string_type & start_delim, 
    const string_type & open_end_delim, 
    const string_type & closed_end_delim) ;
  7. template<typename period_type, typename facet_type> 
    OutItrT put_period(OutItrT next, std::ios_base & a_ios, char_type a_fill, 
    const period_type & p, const facet_type & facet) const;

    This generic code will output any period using a facet to to output the 'elements'. For example, in the case of a date_period the elements will be instances of a date which will be formatted according the to setup in the passed facet parameter.

    The steps for formatting a period are always the same:

    • put the start delimiter

    • put start element

    • put the separator

    • put either last or end element depending on range settings

    • put end delimeter depending on range settings

    Thus for a typical date period the result might look like this:

        [March 01, 2004/June 07, 2004]   <-- closed range
        [March 01, 2004/June 08, 2004)   <-- open range
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