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Class template partial_date

boost::date_time::partial_date — Generates a date by applying the year to the given month and day.


// In header: <boost/date_time/date_generators.hpp>

template<typename date_type> 
class partial_date :
  public boost::date_time::year_based_generator< date_type >
  // types
  typedef date_type::calendar_type    calendar_type;
  typedef calendar_type::day_type     day_type;     
  typedef calendar_type::month_type   month_type;   
  typedef calendar_type::year_type    year_type;    
  typedef date_type::duration_type    duration_type;
  typedef duration_type::duration_rep duration_rep; 

  // construct/copy/destruct
  partial_date(day_type, month_type);

  // public member functions
  virtual date_type get_date(year_type) const;
  date_type operator()(year_type) const;
  bool operator==(const partial_date &) const;
  bool operator<(const partial_date &) const;
  month_type month() const;
  day_type day() const;
  virtual std::string to_string() const;


Example usage:

partial_date pd(1, Jan);
partial_date pd2(70);
date d = pd.get_date(2002); //2002-Jan-01
date d2 = pd2.get_date(2002); //2002-Mar-10

partial_date public construct/copy/destruct

  1. partial_date(day_type d, month_type m);
  2. partial_date(duration_rep days);
    Partial date created from number of days into year. Range 1-366.

    Allowable values range from 1 to 366. 1=Jan1, 366=Dec31. If argument exceeds range, partial_date will be created with closest in-range value. 60 will always be Feb29, if get_date() is called with a non-leap year an exception will be thrown

partial_date public member functions

  1. virtual date_type get_date(year_type y) const;
    Return a concrete date when provided with a year specific year.

    Will throw an 'invalid_argument' exception if a partial_date object, instantiated with Feb-29, has get_date called with a non-leap year. Example:

    partial_date pd(29, Feb);
    pd.get_date(2003); // throws invalid_argument exception
    pg.get_date(2000); // returns 2000-2-29

  2. date_type operator()(year_type y) const;
  3. bool operator==(const partial_date & rhs) const;
  4. bool operator<(const partial_date & rhs) const;
  5. month_type month() const;
  6. day_type day() const;
  7. virtual std::string to_string() const;
    Returns string suitable for use in POSIX time zone string.

    Returns string formatted with up to 3 digits: Jan-01 == "0" Feb-29 == "58" Dec-31 == "365"