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Class template wrapping_int2

boost::date_time::wrapping_int2 — A wrapping integer used to wrap around at the top (WARNING: only instantiate with a signed type)


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

template<typename int_type_, int_type_ wrap_min, int_type_ wrap_max> 
class wrapping_int2 {
  // types
  typedef int_type_ int_type;

  // construct/copy/destruct

  // public static functions
  static BOOST_CONSTEXPR int_type wrap_value();
  static BOOST_CONSTEXPR int_type min_value();

  // public member functions
  BOOST_CONSTEXPR int_type as_int() const;
  BOOST_CONSTEXPR operator int_type() const;
  template<typename IntT> BOOST_CXX14_CONSTEXPR IntT add(IntT);
  template<typename IntT> BOOST_CXX14_CONSTEXPR IntT subtract(IntT);

  // private member functions
  template<typename IntT> BOOST_CXX14_CONSTEXPR IntT calculate_wrap(IntT);


Bad name, quick impl to fix a bug – fix later!! This allows the wrap to restart at a value other than 0.

wrapping_int2 public construct/copy/destruct

  1. wrapping_int2(int_type v);

    If initializing value is out of range of [wrap_min, wrap_max], value will be initialized to closest of min or max

wrapping_int2 public static functions

  1. static BOOST_CONSTEXPR int_type wrap_value();
  2. static BOOST_CONSTEXPR int_type min_value();

wrapping_int2 public member functions

  1. BOOST_CONSTEXPR int_type as_int() const;
    Explicit converion method.
  2. BOOST_CONSTEXPR operator int_type() const;
  3. template<typename IntT> BOOST_CXX14_CONSTEXPR IntT add(IntT v);
    Add, return number of wraps performed.

    The sign of the returned value will indicate which direction the wraps went. Ex: add a negative number and wrapping under could occur, this would be indicated by a negative return value. If wrapping over took place, a positive value would be returned

  4. template<typename IntT> BOOST_CXX14_CONSTEXPR IntT subtract(IntT v);
    Subtract will return '-d' if wrapping under took place ('d' is the number of wraps)

    The sign of the returned value will indicate which direction the wraps went. Ex: subtract a negative number and wrapping over could occur, this would be indicated by a positive return value. If wrapping under took place, a negative value would be returned

wrapping_int2 private member functions

  1. template<typename IntT> BOOST_CXX14_CONSTEXPR IntT calculate_wrap(IntT wrap);