text: // The template and inlines for the -*- C++ -*- internal _Meta class.
  
  // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
  // 2009  Free Software Foundation, Inc.
  //
  // This file is part of the GNU ISO C++ Library.  This library is free
  // software; you can redistribute it and/or modify it under the
  // terms of the GNU General Public License as published by the
  // Free Software Foundation; either version 3, or (at your option)
  // any later version.
  
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  // GNU General Public License for more details.
  
  // Under Section 7 of GPL version 3, you are granted additional
  // permissions described in the GCC Runtime Library Exception, version
  // 3.1, as published by the Free Software Foundation.
  
  // You should have received a copy of the GNU General Public License and
  // a copy of the GCC Runtime Library Exception along with this program;
  // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  // <http://www.gnu.org/licenses/>.
  
  /** @file valarray_after.h
   *  This is an internal header file, included by other library headers.
   *  You should not attempt to use it directly.
   */
  
  // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@cmla.ens-cachan.fr>
  
  #ifndef _VALARRAY_AFTER_H
  #define _VALARRAY_AFTER_H 1
  
  #pragma GCC system_header
  
  _GLIBCXX_BEGIN_NAMESPACE(std)
  
    //
    // gslice_array closure.
    //
    template<class _Dom>
      class _GBase
      {
      public:
        typedef typename _Dom::value_type value_type;
  
        _GBase (const _Dom& __e, const valarray<size_t>& __i)
        : _M_expr (__e), _M_index(__i) {}
  
        value_type
        operator[] (size_t __i) const
        { return _M_expr[_M_index[__i]]; }
  
        size_t
        size () const
        { return _M_index.size(); }
  
      private:
        const _Dom&	      _M_expr;
        const valarray<size_t>& _M_index;
      };
  
    template<typename _Tp>
      class _GBase<_Array<_Tp> >
      {
      public:
        typedef _Tp value_type;
  
        _GBase (_Array<_Tp> __a, const valarray<size_t>& __i)
        : _M_array (__a), _M_index(__i) {}
  
        value_type
        operator[] (size_t __i) const
        { return _M_array._M_data[_M_index[__i]]; }
  
        size_t
        size () const
        { return _M_index.size(); }
  
      private:
        const _Array<_Tp>       _M_array;
        const valarray<size_t>& _M_index;
      };
  
    template<class _Dom>
      struct _GClos<_Expr, _Dom>
      : _GBase<_Dom>
      {
        typedef _GBase<_Dom> _Base;
        typedef typename _Base::value_type value_type;
  
        _GClos (const _Dom& __e, const valarray<size_t>& __i)
        : _Base (__e, __i) {}
      };
  
    template<typename _Tp>
      struct _GClos<_ValArray, _Tp>
      : _GBase<_Array<_Tp> >
      {
        typedef _GBase<_Array<_Tp> > _Base;
        typedef typename _Base::value_type value_type;
  
        _GClos (_Array<_Tp> __a, const valarray<size_t>& __i)
        : _Base (__a, __i) {}
      };
  
    //
    // indirect_array closure
    //
    template<class _Dom>
      class _IBase
      {
      public:
        typedef typename _Dom::value_type value_type;
  
        _IBase (const _Dom& __e, const valarray<size_t>& __i)
        : _M_expr (__e), _M_index (__i) {}
  
        value_type
        operator[] (size_t __i) const
        { return _M_expr[_M_index[__i]]; }
  
        size_t
        size() const
        { return _M_index.size(); }
  
      private:
        const _Dom&	      _M_expr;
        const valarray<size_t>& _M_index;
      };
  
    template<class _Dom>
      struct _IClos<_Expr, _Dom>
      : _IBase<_Dom>
      {
        typedef _IBase<_Dom> _Base;
        typedef typename _Base::value_type value_type;
  
        _IClos (const _Dom& __e, const valarray<size_t>& __i)
        : _Base (__e, __i) {}
      };
  
    template<typename _Tp>
      struct _IClos<_ValArray, _Tp>
      : _IBase<valarray<_Tp> >
      {
        typedef _IBase<valarray<_Tp> > _Base;
        typedef _Tp value_type;
  
        _IClos (const valarray<_Tp>& __a, const valarray<size_t>& __i)
        : _Base (__a, __i) {}
      };
  
    //
    // class _Expr
    //
    template<class _Clos, typename _Tp>
      class _Expr
      {
      public:
        typedef _Tp value_type;
  
        _Expr(const _Clos&);
  
        const _Clos& operator()() const;
  
        value_type operator[](size_t) const;
        valarray<value_type> operator[](slice) const;
        valarray<value_type> operator[](const gslice&) const;
        valarray<value_type> operator[](const valarray<bool>&) const;
        valarray<value_type> operator[](const valarray<size_t>&) const;
  
        _Expr<_UnClos<__unary_plus, std::_Expr, _Clos>, value_type>
        operator+() const;
  
        _Expr<_UnClos<__negate, std::_Expr, _Clos>, value_type>
        operator-() const;
  
        _Expr<_UnClos<__bitwise_not, std::_Expr, _Clos>, value_type>
        operator~() const;
  
        _Expr<_UnClos<__logical_not, std::_Expr, _Clos>, bool>
        operator!() const;
  
        size_t size() const;
        value_type sum() const;
  
        valarray<value_type> shift(int) const;
        valarray<value_type> cshift(int) const;
  
        value_type min() const;
        value_type max() const;
  
        valarray<value_type> apply(value_type (*)(const value_type&)) const;
        valarray<value_type> apply(value_type (*)(value_type)) const;
  
      private:
        const _Clos _M_closure;
      };
  
    template<class _Clos, typename _Tp>
      inline
      _Expr<_Clos, _Tp>::_Expr(const _Clos& __c) : _M_closure(__c) {}
  
    template<class _Clos, typename _Tp>
      inline const _Clos&
      _Expr<_Clos, _Tp>::operator()() const
      { return _M_closure; }
  
    template<class _Clos, typename _Tp>
      inline _Tp
      _Expr<_Clos, _Tp>::operator[](size_t __i) const
      { return _M_closure[__i]; }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::operator[](slice __s) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this)[__s];
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::operator[](const gslice& __gs) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this)[__gs];
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::operator[](const valarray<bool>& __m) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this)[__m];
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::operator[](const valarray<size_t>& __i) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this)[__i];
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline size_t
      _Expr<_Clos, _Tp>::size() const
      { return _M_closure.size(); }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::shift(int __n) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this).shift(__n);
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::cshift(int __n) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this).cshift(__n);
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::apply(_Tp __f(const _Tp&)) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this).apply(__f);
        return __v;
      }
  
    template<class _Clos, typename _Tp>
      inline valarray<_Tp>
      _Expr<_Clos, _Tp>::apply(_Tp __f(_Tp)) const
      {
        valarray<_Tp> __v = valarray<_Tp>(*this).apply(__f);
        return __v;
      }
  
    // XXX: replace this with a more robust summation algorithm.
    template<class _Clos, typename _Tp>
      inline _Tp
      _Expr<_Clos, _Tp>::sum() const
      {
        size_t __n = _M_closure.size();
        if (__n == 0)
  	return _Tp();
        else
  	{
  	  _Tp __s = _M_closure[--__n];
  	  while (__n != 0)
  	    __s += _M_closure[--__n];
  	  return __s;
          }
      }
  
    template<class _Clos, typename _Tp>
      inline _Tp
      _Expr<_Clos, _Tp>::min() const
      { return __valarray_min(_M_closure); }
  
    template<class _Clos, typename _Tp>
      inline _Tp
      _Expr<_Clos, _Tp>::max() const
      { return __valarray_max(_M_closure); }
  
    template<class _Dom, typename _Tp>
      inline _Expr<_UnClos<__logical_not, _Expr, _Dom>, bool>
      _Expr<_Dom, _Tp>::operator!() const
      {
        typedef _UnClos<__logical_not, std::_Expr, _Dom> _Closure;
        return _Expr<_Closure, bool>(_Closure(this->_M_closure));
      }
  
  #define _DEFINE_EXPR_UNARY_OPERATOR(_Op, _Name)                           \
    template<class _Dom, typename _Tp>                                      \
      inline _Expr<_UnClos<_Name, std::_Expr, _Dom>, _Tp>                   \
      _Expr<_Dom, _Tp>::operator _Op() const                                \
      {                                                                     \
        typedef _UnClos<_Name, std::_Expr, _Dom> _Closure;                  \
        return _Expr<_Closure, _Tp>(_Closure(this->_M_closure));            \
      }
  
      _DEFINE_EXPR_UNARY_OPERATOR(+, __unary_plus)
      _DEFINE_EXPR_UNARY_OPERATOR(-, __negate)
      _DEFINE_EXPR_UNARY_OPERATOR(~, __bitwise_not)
  
  #undef _DEFINE_EXPR_UNARY_OPERATOR
  
  #define _DEFINE_EXPR_BINARY_OPERATOR(_Op, _Name)                        \
    template<class _Dom1, class _Dom2>					\
      inline _Expr<_BinClos<_Name, _Expr, _Expr, _Dom1, _Dom2>,           \
             typename __fun<_Name, typename _Dom1::value_type>::result_type> \
      operator _Op(const _Expr<_Dom1, typename _Dom1::value_type>& __v,   \
  	         const _Expr<_Dom2, typename _Dom2::value_type>& __w)   \
      {                                                                   \
        typedef typename _Dom1::value_type _Arg;                          \
        typedef typename __fun<_Name, _Arg>::result_type _Value;          \
        typedef _BinClos<_Name, _Expr, _Expr, _Dom1, _Dom2> _Closure;     \
        return _Expr<_Closure, _Value>(_Closure(__v(), __w()));           \
      }                                                                   \
                                                                          \
    template<class _Dom>                                                  \
      inline _Expr<_BinClos<_Name, _Expr, _Constant, _Dom,                \
                            typename _Dom::value_type>,                   \
               typename __fun<_Name, typename _Dom::value_type>::result_type> \
      operator _Op(const _Expr<_Dom, typename _Dom::value_type>& __v,     \
                   const typename _Dom::value_type& __t)                  \
      {                                                                   \
        typedef typename _Dom::value_type _Arg;                           \
        typedef typename __fun<_Name, _Arg>::result_type _Value;          \
        typedef _BinClos<_Name, _Expr, _Constant, _Dom, _Arg> _Closure;   \
        return _Expr<_Closure, _Value>(_Closure(__v(), __t));             \
      }                                                                   \
                                                                          \
    template<class _Dom>                                                  \
      inline _Expr<_BinClos<_Name, _Constant, _Expr,                      \
                            typename _Dom::value_type, _Dom>,             \
               typename __fun<_Name, typename _Dom::value_type>::result_type> \
      operator _Op(const typename _Dom::value_type& __t,                  \
                   const _Expr<_Dom, typename _Dom::value_type>& __v)     \
      {                                                                   \
        typedef typename _Dom::value_type _Arg;                           \
        typedef typename __fun<_Name, _Arg>::result_type _Value;          \
        typedef _BinClos<_Name, _Constant, _Expr, _Arg, _Dom> _Closure;   \
        return _Expr<_Closure, _Value>(_Closure(__t, __v()));             \
      }                                                                   \
                                                                          \
    template<class _Dom>                                                  \
      inline _Expr<_BinClos<_Name, _Expr, _ValArray,                      \
                            _Dom, typename _Dom::value_type>,             \
               typename __fun<_Name, typename _Dom::value_type>::result_type> \
      operator _Op(const _Expr<_Dom,typename _Dom::value_type>& __e,      \
                   const valarray<typename _Dom::value_type>& __v)        \
      {                                                                   \
        typedef typename _Dom::value_type _Arg;                           \
        typedef typename __fun<_Name, _Arg>::result_type _Value;          \
        typedef _BinClos<_Name, _Expr, _ValArray, _Dom, _Arg> _Closure;   \
        return _Expr<_Closure, _Value>(_Closure(__e(), __v));             \
      }                                                                   \
                                                                          \
    template<class _Dom>                                                  \
      inline _Expr<_BinClos<_Name, _ValArray, _Expr,                      \
                   typename _Dom::value_type, _Dom>,                      \
               typename __fun<_Name, typename _Dom::value_type>::result_type> \
      operator _Op(const valarray<typename _Dom::value_type>& __v,        \
                   const _Expr<_Dom, typename _Dom::value_type>& __e)     \
      {                                                                   \
        typedef typename _Dom::value_type _Tp;                            \
        typedef typename __fun<_Name, _Tp>::result_type _Value;           \
        typedef _BinClos<_Name, _ValArray, _Expr, _Tp, _Dom> _Closure;    \
        return _Expr<_Closure, _Value>(_Closure(__v, __e ()));            \
      }
  
      _DEFINE_EXPR_BINARY_OPERATOR(+, __plus)
      _DEFINE_EXPR_BINARY_OPERATOR(-, __minus)
      _DEFINE_EXPR_BINARY_OPERATOR(*, __multiplies)
      _DEFINE_EXPR_BINARY_OPERATOR(/, __divides)
      _DEFINE_EXPR_BINARY_OPERATOR(%, __modulus)
      _DEFINE_EXPR_BINARY_OPERATOR(^, __bitwise_xor)
      _DEFINE_EXPR_BINARY_OPERATOR(&, __bitwise_and)
      _DEFINE_EXPR_BINARY_OPERATOR(|, __bitwise_or)
      _DEFINE_EXPR_BINARY_OPERATOR(<<, __shift_left)
      _DEFINE_EXPR_BINARY_OPERATOR(>>, __shift_right)
      _DEFINE_EXPR_BINARY_OPERATOR(&&, __logical_and)
      _DEFINE_EXPR_BINARY_OPERATOR(||, __logical_or)
      _DEFINE_EXPR_BINARY_OPERATOR(==, __equal_to)
      _DEFINE_EXPR_BINARY_OPERATOR(!=, __not_equal_to)
      _DEFINE_EXPR_BINARY_OPERATOR(<, __less)
      _DEFINE_EXPR_BINARY_OPERATOR(>, __greater)
      _DEFINE_EXPR_BINARY_OPERATOR(<=, __less_equal)
      _DEFINE_EXPR_BINARY_OPERATOR(>=, __greater_equal)
  
  #undef _DEFINE_EXPR_BINARY_OPERATOR
  
  #define _DEFINE_EXPR_UNARY_FUNCTION(_Name)                               \
    template<class _Dom>                                                   \
      inline _Expr<_UnClos<__##_Name, _Expr, _Dom>,                        \
                   typename _Dom::value_type>                              \
      _Name(const _Expr<_Dom, typename _Dom::value_type>& __e)             \
      {                                                                    \
        typedef typename _Dom::value_type _Tp;                             \
        typedef _UnClos<__##_Name, _Expr, _Dom> _Closure;                  \
        return _Expr<_Closure, _Tp>(_Closure(__e()));                      \
      }                                                                    \
                                                                           \
    template<typename _Tp>                                                 \
      inline _Expr<_UnClos<__##_Name, _ValArray, _Tp>, _Tp>                \
      _Name(const valarray<_Tp>& __v)                                      \
      {                                                                    \
        typedef _UnClos<__##_Name, _ValArray, _Tp> _Closure;               \
        return _Expr<_Closure, _Tp>(_Closure(__v));                        \
      }
  
      _DEFINE_EXPR_UNARY_FUNCTION(abs)
      _DEFINE_EXPR_UNARY_FUNCTION(cos)
      _DEFINE_EXPR_UNARY_FUNCTION(acos)
      _DEFINE_EXPR_UNARY_FUNCTION(cosh)
      _DEFINE_EXPR_UNARY_FUNCTION(sin)
      _DEFINE_EXPR_UNARY_FUNCTION(asin)
      _DEFINE_EXPR_UNARY_FUNCTION(sinh)
      _DEFINE_EXPR_UNARY_FUNCTION(tan)
      _DEFINE_EXPR_UNARY_FUNCTION(tanh)
      _DEFINE_EXPR_UNARY_FUNCTION(atan)
      _DEFINE_EXPR_UNARY_FUNCTION(exp)
      _DEFINE_EXPR_UNARY_FUNCTION(log)
      _DEFINE_EXPR_UNARY_FUNCTION(log10)
      _DEFINE_EXPR_UNARY_FUNCTION(sqrt)
  
  #undef _DEFINE_EXPR_UNARY_FUNCTION
  
  #define _DEFINE_EXPR_BINARY_FUNCTION(_Fun)                             \
    template<class _Dom1, class _Dom2>                                   \
      inline _Expr<_BinClos<__##_Fun, _Expr, _Expr, _Dom1, _Dom2>,       \
  		 typename _Dom1::value_type>                           \
      _Fun(const _Expr<_Dom1, typename _Dom1::value_type>& __e1,         \
  	  const _Expr<_Dom2, typename _Dom2::value_type>& __e2)        \
      {                                                                  \
        typedef typename _Dom1::value_type _Tp;                          \
        typedef _BinClos<__##_Fun, _Expr, _Expr, _Dom1, _Dom2> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__e1(), __e2()));           \
      }                                                                  \
                                                                         \
    template<class _Dom>                                                 \
      inline _Expr<_BinClos<__##_Fun, _Expr, _ValArray, _Dom,            \
  			  typename _Dom::value_type>,                  \
  		 typename _Dom::value_type>                            \
      _Fun(const _Expr<_Dom, typename _Dom::value_type>& __e,            \
  	 const valarray<typename _Dom::value_type>& __v)               \
      {                                                                  \
        typedef typename _Dom::value_type _Tp;                           \
        typedef _BinClos<__##_Fun, _Expr, _ValArray, _Dom, _Tp> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__e(), __v));               \
      }                                                                  \
                                                                         \
    template<class _Dom>                                                 \
      inline _Expr<_BinClos<__##_Fun, _ValArray, _Expr,                  \
  			  typename _Dom::value_type, _Dom>,            \
  		 typename _Dom::value_type>                            \
      _Fun(const valarray<typename _Dom::valarray>& __v,                 \
  	 const _Expr<_Dom, typename _Dom::value_type>& __e)            \
      {                                                                  \
        typedef typename _Dom::value_type _Tp;                           \
        typedef _BinClos<__##_Fun, _ValArray, _Expr, _Tp, _Dom> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__v, __e()));               \
      }                                                                  \
                                                                         \
    template<class _Dom>                                                 \
      inline _Expr<_BinClos<__##_Fun, _Expr, _Constant, _Dom,            \
  			  typename _Dom::value_type>,                  \
  		 typename _Dom::value_type>                            \
      _Fun(const _Expr<_Dom, typename _Dom::value_type>& __e,            \
  	 const typename _Dom::value_type& __t)                         \
      {                                                                  \
        typedef typename _Dom::value_type _Tp;                           \
        typedef _BinClos<__##_Fun, _Expr, _Constant, _Dom, _Tp> _Closure;\
        return _Expr<_Closure, _Tp>(_Closure(__e(), __t));               \
      }                                                                  \
                                                                         \
    template<class _Dom>                                                 \
      inline _Expr<_BinClos<__##_Fun, _Constant, _Expr,                  \
  			  typename _Dom::value_type, _Dom>,            \
  		 typename _Dom::value_type>                            \
      _Fun(const typename _Dom::value_type& __t,                         \
  	 const _Expr<_Dom, typename _Dom::value_type>& __e)            \
      {                                                                  \
        typedef typename _Dom::value_type _Tp;                           \
        typedef _BinClos<__##_Fun, _Constant, _Expr, _Tp, _Dom> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__t, __e()));               \
      }                                                                  \
                                                                         \
    template<typename _Tp>                                               \
      inline _Expr<_BinClos<__##_Fun, _ValArray, _ValArray, _Tp, _Tp>, _Tp> \
      _Fun(const valarray<_Tp>& __v, const valarray<_Tp>& __w)           \
      {                                                                  \
        typedef _BinClos<__##_Fun, _ValArray, _ValArray, _Tp, _Tp> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__v, __w));                 \
      }                                                                  \
                                                                         \
    template<typename _Tp>                                               \
      inline _Expr<_BinClos<__##_Fun, _ValArray, _Constant, _Tp, _Tp>, _Tp> \
      _Fun(const valarray<_Tp>& __v, const _Tp& __t)                     \
      {                                                                  \
        typedef _BinClos<__##_Fun, _ValArray, _Constant, _Tp, _Tp> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__v, __t));                 \
      }                                                                  \
  								       \
    template<typename _Tp>                                               \
      inline _Expr<_BinClos<__##_Fun, _Constant, _ValArray, _Tp, _Tp>, _Tp> \
      _Fun(const _Tp& __t, const valarray<_Tp>& __v)                     \
      {                                                                  \
        typedef _BinClos<__##_Fun, _Constant, _ValArray, _Tp, _Tp> _Closure; \
        return _Expr<_Closure, _Tp>(_Closure(__t, __v));                 \
      }
  
  _DEFINE_EXPR_BINARY_FUNCTION(atan2)
  _DEFINE_EXPR_BINARY_FUNCTION(pow)
  
  #undef _DEFINE_EXPR_BINARY_FUNCTION
  
  _GLIBCXX_END_NAMESPACE
  
  #endif /* _CPP_VALARRAY_AFTER_H */
  