_Circ_buf< _Ty, _Nw > Struct Template Reference

Public Member Functions
_Ty	_At (int _Ix) const
bool	_Equals (const _Circ_buf &_Right) const
unsigned int	_Base (int _Ix=0) const

Public Attributes
unsigned int	_Idx
_Ty	_Ax [2 *_Nw]

Member Function Documentation

template<class _Ty, size_t _Nw>

_Ty _Circ_buf< _Ty, _Nw >::_At ( int  _Ix ) const

inline

        {   // return value at current position plus _Ix
        return (_Ax[_Base(_Ix)]);
        }

template<class _Ty, size_t _Nw>

unsigned int _Circ_buf< _Ty, _Nw >::_Base ( int  _Ix = 0 ) const

inline

        {   // return _Ix'th historical element (loosely, (_Idx - _Nw) + _Ix)
        return ((_Ix += _Idx) < _Nw ? (_Ix + _Nw) : (_Ix - _Nw));
        }

template<class _Ty, size_t _Nw>

bool _Circ_buf< _Ty, _Nw >::_Equals ( const _Circ_buf< _Ty, _Nw > &  _Right ) const

inline

        {   // return true if *this holds same values as _Right
        const _Ty *_Last1 = _Ax + _Idx;
        const _Ty *_Last2 = _Right._Ax + _Right._Idx;
        const _Ty *_First, *_Last, *_Other;
        bool _Use2 = _Base() < _Right._Base();

        if (_Use2)
            {   // _Right's range is higher up in the array
                // than ours, so scan it first
            _First = _Right._Ax + _Right._Base();
            _Last = _Last2;
            _Other = _Ax + _Base();
            }
        else
            {   // our range is higher up in the array
                // than _Right's, so scan ours first
            _First = _Ax + _Base();
            _Last = _Last1;
            _Other = _Right._Ax + _Right._Base();
            }

        ptrdiff_t _N0 = _Nw;
        while (0 < _N0)
            {   // scan
                // note: may need up to three passes; each scan starts at the
                // current highest array position and ends at the end of the
                // array or the _Idx value, whichever comes first; the
                // equality test succeeds only by reaching the _Idx value.
            const _Ty *_Limit = _First < _Last ? _Last
                : _Use2 ? _Right._Ax + 2 * _Nw
                : _Ax + 2 * _Nw;
            _N0 -= _Limit - _First;
            while (_First != _Limit)
                if (*_First++ != *_Other++)
                    return (false);
            _First = _Other;
            _Last = _Use2 ? _Last1 : _Last2;
            _Other = _Use2 ? _Right._Ax : _Ax;
            _Use2 = !_Use2;
            }
        return (true);
        }

Member Data Documentation

template<class _Ty, size_t _Nw>

_Ty _Circ_buf< _Ty, _Nw >::_Ax[2 *_Nw]

template<class _Ty, size_t _Nw>

unsigned int _Circ_buf< _Ty, _Nw >::_Idx

---

The documentation for this struct was generated from the following file:

• VS2013/inc/random