// Copyright (C) 2010-2014 National ICT Australia (NICTA)
// 
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
// -------------------------------------------------------------------
// 
// Written by Conrad Sanderson - http://conradsanderson.id.au


//! \addtogroup Proxy
//! @{


// ea_type is the "element accessor" type,
// which can provide access to elements via operator[]



template<typename T1>
struct Proxy_default
  {
  inline Proxy_default(const T1&)
    {
    arma_type_check(( is_arma_type<T1>::value == false ));
    }
  };



template<typename T1>
struct Proxy_fixed
  {
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef T1                                       stored_type;
  typedef const elem_type*                         ea_type;
  typedef const T1&                                aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = T1::is_row;
  static const bool is_col = T1::is_col;
  
  arma_aligned const T1& Q;
  
  inline explicit Proxy_fixed(const T1& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline static uword get_n_rows() { return T1::n_rows; }
  arma_inline static uword get_n_cols() { return T1::n_cols; }
  arma_inline static uword get_n_elem() { return T1::n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&Q) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const
    {
    #if defined(ARMA_HAVE_ALIGNED_ATTRIBUTE)
      return true;
    #else
      return memory::is_aligned(Q.memptr());
    #endif
    }
  };



template<typename T1, bool condition>
struct Proxy_redirect {};

template<typename T1>
struct Proxy_redirect<T1, false> { typedef Proxy_default<T1> result; };

template<typename T1>
struct Proxy_redirect<T1, true>  { typedef Proxy_fixed<T1>   result; };



template<typename T1>
class Proxy : public Proxy_redirect<T1, is_Mat_fixed<T1>::value >::result
  {
  public:
  inline Proxy(const T1& A)
    : Proxy_redirect< T1, is_Mat_fixed<T1>::value >::result(A)
    {
    }
  };



template<typename eT>
class Proxy< Mat<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Mat<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  arma_aligned const Mat<eT>& Q;
  
  inline explicit Proxy(const Mat<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&Q) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT>
class Proxy< Col<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Col<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Col<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const Col<eT>& Q;
  
  inline explicit Proxy(const Col<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];        }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row];      }
  arma_inline elem_type at_alt     (const uword i)                const { return Q.at_alt(i); }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&Q) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT>
class Proxy< Row<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Row<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Row<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = true;
  static const bool is_col = false;
  
  arma_aligned const Row<eT>& Q;
  
  inline explicit Proxy(const Row<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return 1;        }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];        }
  arma_inline elem_type at         (const uword, const uword col) const { return Q[col];      }
  arma_inline elem_type at_alt     (const uword i)                const { return Q.at_alt(i); }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&Q) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1, typename gen_type>
class Proxy< Gen<T1, gen_type > >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Gen<T1, gen_type>                        stored_type;
  typedef const Gen<T1, gen_type>&                 ea_type;
  typedef const Gen<T1, gen_type>&                 aligned_ea_type;
  
  static const bool prefer_at_accessor = Gen<T1, gen_type>::prefer_at_accessor;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = Gen<T1, gen_type>::is_row;
  static const bool is_col = Gen<T1, gen_type>::is_col;
  
  arma_aligned const Gen<T1, gen_type>& Q;
  
  inline explicit Proxy(const Gen<T1, gen_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return (is_row ? 1 : Q.n_rows);                           }
  arma_inline uword get_n_cols() const { return (is_col ? 1 : Q.n_cols);                           }
  arma_inline uword get_n_elem() const { return (is_row ? 1 : Q.n_rows) * (is_col ? 1 : Q.n_cols); }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q[i];           }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return Gen<T1, gen_type>::is_simple; }
  };



template<typename T1, typename op_type>
class Proxy< Op<T1, op_type> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = Op<T1, op_type>::is_row;
  static const bool is_col = Op<T1, op_type>::is_col;
  
  arma_aligned const Mat<elem_type> Q;
  
  inline explicit Proxy(const Op<T1, op_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1>
class Proxy_diagvec_mat
  {
  inline Proxy_diagvec_mat(const T1&) {}
  };



template<typename T1>
class Proxy_diagvec_mat< Op<T1, op_diagvec> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef diagview<elem_type>                      stored_type;
  typedef const diagview<elem_type>&               ea_type;
  typedef const diagview<elem_type>&               aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const Mat<elem_type>&     R;
  arma_aligned const diagview<elem_type> Q;
  
  inline explicit Proxy_diagvec_mat(const Op<T1, op_diagvec>& A)
    : R(A.m), Q( R.diag( (A.aux_uword_b > 0) ? -sword(A.aux_uword_a) : sword(A.aux_uword_a) ) )
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];         }
  arma_inline elem_type at         (const uword row, const uword) const { return Q.at(row, 0); }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];         }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&R) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T1>
class Proxy_diagvec_expr
  {
  inline Proxy_diagvec_expr(const T1&) {}
  };



template<typename T1>
class Proxy_diagvec_expr< Op<T1, op_diagvec> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const Mat<elem_type> Q;
  
  inline explicit Proxy_diagvec_expr(const Op<T1, op_diagvec>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];         }
  arma_inline elem_type at         (const uword row, const uword) const { return Q.at(row, 0); }
  arma_inline elem_type at_alt     (const uword i)                const { return Q.at_alt(i);  }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1, bool condition>
struct Proxy_diagvec_redirect {};

template<typename T1>
struct Proxy_diagvec_redirect< Op<T1, op_diagvec>, true > { typedef Proxy_diagvec_mat < Op<T1, op_diagvec> > result; };

template<typename T1>
struct Proxy_diagvec_redirect< Op<T1, op_diagvec>, false> { typedef Proxy_diagvec_expr< Op<T1, op_diagvec> > result; };



template<typename T1>
class Proxy< Op<T1, op_diagvec> >
  : public Proxy_diagvec_redirect< Op<T1, op_diagvec>, is_Mat<T1>::value >::result
  {
  public:
  
  typedef typename Proxy_diagvec_redirect< Op<T1, op_diagvec>, is_Mat<T1>::value >::result Proxy_diagvec;
  
  inline explicit Proxy(const Op<T1, op_diagvec>& A)
    : Proxy_diagvec(A)
    {
    arma_extra_debug_sigprint();
    }
  };



template<typename T1>
struct Proxy_xtrans_default
  {
  inline Proxy_xtrans_default(const T1&) {}
  };



template<typename T1>
struct Proxy_xtrans_default< Op<T1, op_htrans> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef xtrans_mat<elem_type,true>               stored_type;
  typedef const xtrans_mat<elem_type,true>&        ea_type;
  typedef const xtrans_mat<elem_type,true>&        aligned_ea_type;
  
  static const bool prefer_at_accessor = true;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  const unwrap<T1>                 U;
  const xtrans_mat<elem_type,true> Q;
  
  inline explicit Proxy_xtrans_default(const Op<T1, op_htrans>& A)
    : U(A.m)
    , Q(U.M)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return void_ptr(&(U.M)) == void_ptr(&X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T1>
struct Proxy_xtrans_default< Op<T1, op_strans> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef xtrans_mat<elem_type,false>              stored_type;
  typedef const xtrans_mat<elem_type,false>&       ea_type;
  typedef const xtrans_mat<elem_type,false>&       aligned_ea_type;
  
  static const bool prefer_at_accessor = true;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  const unwrap<T1>                  U;
  const xtrans_mat<elem_type,false> Q;
  
  inline explicit Proxy_xtrans_default(const Op<T1, op_strans>& A)
    : U(A.m)
    , Q(U.M)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return void_ptr(&(U.M)) == void_ptr(&X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T1>
struct Proxy_xtrans_vector
  {
  inline Proxy_xtrans_vector(const T1&) {}
  };



template<typename T1>
struct Proxy_xtrans_vector< Op<T1, op_htrans> >
  {
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = quasi_unwrap<T1>::has_subview;
  static const bool fake_mat           = true;
  
  // NOTE: the Op class takes care of swapping row and col for op_htrans
  static const bool is_row = Op<T1, op_htrans>::is_row;
  static const bool is_col = Op<T1, op_htrans>::is_col;
  
  arma_aligned const quasi_unwrap<T1> U; // avoid copy if T1 is a Row, Col or subview_col
  arma_aligned const Mat<elem_type>   Q;
  
  inline Proxy_xtrans_vector(const Op<T1, op_htrans>& A)
    : U(A.m)
    , Q(const_cast<elem_type*>(U.M.memptr()), U.M.n_cols, U.M.n_rows, false, false)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return U.is_alias(X); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1>
struct Proxy_xtrans_vector< Op<T1, op_strans> >
  {
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = quasi_unwrap<T1>::has_subview;
  static const bool fake_mat           = true;
  
  // NOTE: the Op class takes care of swapping row and col for op_htrans
  static const bool is_row = Op<T1, op_htrans>::is_row;
  static const bool is_col = Op<T1, op_htrans>::is_col;
  
  arma_aligned const quasi_unwrap<T1> U; // avoid copy if T1 is a Row, Col or subview_col
  arma_aligned const Mat<elem_type>   Q;
  
  inline Proxy_xtrans_vector(const Op<T1, op_strans>& A)
    : U(A.m)
    , Q(const_cast<elem_type*>(U.M.memptr()), U.M.n_cols, U.M.n_rows, false, false)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return U.is_alias(X); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1, bool condition>
struct Proxy_xtrans_redirect {};

template<typename T1>
struct Proxy_xtrans_redirect<T1, false> { typedef Proxy_xtrans_default<T1> result; };

template<typename T1>
struct Proxy_xtrans_redirect<T1, true>  { typedef Proxy_xtrans_vector<T1>  result; };



template<typename T1>
class Proxy< Op<T1, op_htrans> >
  : public
    Proxy_xtrans_redirect
      <
      Op<T1, op_htrans>,
      ((is_complex<typename T1::elem_type>::value == false) && ((Op<T1, op_htrans>::is_row) || (Op<T1, op_htrans>::is_col)) )
      >::result
  {
  public:
  
  typedef
  typename
  Proxy_xtrans_redirect
    <
    Op<T1, op_htrans>,
    ((is_complex<typename T1::elem_type>::value == false) && ((Op<T1, op_htrans>::is_row) || (Op<T1, op_htrans>::is_col)) )
    >::result
  Proxy_xtrans;
  
  typedef typename Proxy_xtrans::elem_type       elem_type;
  typedef typename Proxy_xtrans::pod_type        pod_type;
  typedef typename Proxy_xtrans::stored_type     stored_type;
  typedef typename Proxy_xtrans::ea_type         ea_type;
  typedef typename Proxy_xtrans::aligned_ea_type aligned_ea_type;
  
  static const bool prefer_at_accessor = Proxy_xtrans::prefer_at_accessor;
  static const bool has_subview        = Proxy_xtrans::has_subview;
  static const bool fake_mat           = Proxy_xtrans::fake_mat;
  
  static const bool is_row = Proxy_xtrans::is_row;
  static const bool is_col = Proxy_xtrans::is_col;
  
  using Proxy_xtrans::Q;
  
  inline explicit Proxy(const Op<T1, op_htrans>& A)
    : Proxy_xtrans(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Proxy_xtrans::get_ea();         }
  arma_inline aligned_ea_type get_aligned_ea() const { return Proxy_xtrans::get_aligned_ea(); }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return Proxy_xtrans::is_alias(X); }
  
  arma_inline bool is_aligned() const { return Proxy_xtrans::is_aligned(); }
  };



template<typename T1>
class Proxy< Op<T1, op_strans> >
  : public
    Proxy_xtrans_redirect
      <
      Op<T1, op_strans>,
      ( (Op<T1, op_strans>::is_row) || (Op<T1, op_strans>::is_col) )
      >::result
  {
  public:
  
  typedef
  typename
  Proxy_xtrans_redirect
    <
    Op<T1, op_strans>,
    ( (Op<T1, op_strans>::is_row) || (Op<T1, op_strans>::is_col) )
    >::result
  Proxy_xtrans;
  
  typedef typename Proxy_xtrans::elem_type       elem_type;
  typedef typename Proxy_xtrans::pod_type        pod_type;
  typedef typename Proxy_xtrans::stored_type     stored_type;
  typedef typename Proxy_xtrans::ea_type         ea_type;
  typedef typename Proxy_xtrans::aligned_ea_type aligned_ea_type;
  
  static const bool prefer_at_accessor = Proxy_xtrans::prefer_at_accessor;
  static const bool has_subview        = Proxy_xtrans::has_subview;
  static const bool fake_mat           = Proxy_xtrans::fake_mat;
  
  static const bool is_row = Proxy_xtrans::is_row;
  static const bool is_col = Proxy_xtrans::is_col;
  
  using Proxy_xtrans::Q;
  
  inline explicit Proxy(const Op<T1, op_strans>& A)
    : Proxy_xtrans(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Proxy_xtrans::get_ea();         }
  arma_inline aligned_ea_type get_aligned_ea() const { return Proxy_xtrans::get_aligned_ea(); }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return Proxy_xtrans::is_alias(X); }
  
  arma_inline bool is_aligned() const { return Proxy_xtrans::is_aligned(); }
  };



template<typename eT>
struct Proxy_subview_row_htrans_cx
  {
  typedef eT                                elem_type;
  typedef typename get_pod_type<eT>::result pod_type;
  typedef subview_row_htrans<eT>            stored_type;
  typedef const subview_row_htrans<eT>&     ea_type;
  typedef const subview_row_htrans<eT>&     aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_row_htrans<eT> Q;
  
  inline explicit Proxy_subview_row_htrans_cx(const Op<subview_row<eT>, op_htrans>& A)
    : Q(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.sv_row.m)) == void_ptr(&X)); }
  };



template<typename eT>
struct Proxy_subview_row_htrans_non_cx
  {
  typedef eT                                elem_type;
  typedef typename get_pod_type<eT>::result pod_type;
  typedef subview_row_strans<eT>            stored_type;
  typedef const subview_row_strans<eT>&     ea_type;
  typedef const subview_row_strans<eT>&     aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_row_strans<eT> Q;
  
  inline explicit Proxy_subview_row_htrans_non_cx(const Op<subview_row<eT>, op_htrans>& A)
    : Q(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.sv_row.m)) == void_ptr(&X)); }
  };



template<typename eT, bool condition>
struct Proxy_subview_row_htrans_redirect {};

template<typename eT>
struct Proxy_subview_row_htrans_redirect<eT, true>  { typedef Proxy_subview_row_htrans_cx<eT>      result; };

template<typename eT>
struct Proxy_subview_row_htrans_redirect<eT, false> { typedef Proxy_subview_row_htrans_non_cx<eT>  result; };



template<typename eT>
class Proxy< Op<subview_row<eT>, op_htrans> >
  : public
    Proxy_subview_row_htrans_redirect
      <
      eT,
      is_complex<eT>::value
      >::result
  {
  public:
  
  typedef
  typename
  Proxy_subview_row_htrans_redirect
      <
      eT,
      is_complex<eT>::value
      >::result
  Proxy_sv_row_ht;
  
  typedef typename Proxy_sv_row_ht::elem_type   elem_type;
  typedef typename Proxy_sv_row_ht::pod_type    pod_type;
  typedef typename Proxy_sv_row_ht::stored_type stored_type;
  typedef typename Proxy_sv_row_ht::ea_type     ea_type;
  typedef typename Proxy_sv_row_ht::ea_type     aligned_ea_type;
  
  static const bool prefer_at_accessor = Proxy_sv_row_ht::prefer_at_accessor;
  static const bool has_subview        = Proxy_sv_row_ht::has_subview;
  static const bool fake_mat           = Proxy_sv_row_ht::fake_mat;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  using Proxy_sv_row_ht::Q;
  
  inline explicit Proxy(const Op<subview_row<eT>, op_htrans>& A)
    : Proxy_sv_row_ht(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return Proxy_sv_row_ht::is_alias(X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT>
class Proxy< Op<subview_row<eT>, op_strans> >
  {
  public:
  
  typedef eT                                elem_type;
  typedef typename get_pod_type<eT>::result pod_type;
  typedef subview_row_strans<eT>            stored_type;
  typedef const subview_row_strans<eT>&     ea_type;
  typedef const subview_row_strans<eT>&     aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_row_strans<eT> Q;
  
  inline explicit Proxy(const Op<subview_row<eT>, op_strans>& A)
    : Q(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.sv_row.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T>
class Proxy< Op< Row< std::complex<T> >, op_htrans> >
  {
  public:
  
  typedef typename std::complex<T>  eT;
  
  typedef typename std::complex<T>  elem_type;
  typedef T                         pod_type;
  typedef xvec_htrans<eT>           stored_type;
  typedef const xvec_htrans<eT>&    ea_type;
  typedef const xvec_htrans<eT>&    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  const xvec_htrans<eT> Q;
  const Row<eT>&        src;
  
  inline explicit Proxy(const Op< Row< std::complex<T> >, op_htrans>& A)
    : Q  (A.m.memptr(), A.m.n_rows, A.m.n_cols)
    , src(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return void_ptr(&src) == void_ptr(&X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T>
class Proxy< Op< Col< std::complex<T> >, op_htrans> >
  {
  public:
  
  typedef typename std::complex<T>  eT;

  typedef typename std::complex<T>  elem_type;
  typedef T                         pod_type;
  typedef xvec_htrans<eT>           stored_type;
  typedef const xvec_htrans<eT>&    ea_type;
  typedef const xvec_htrans<eT>&    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = true;
  static const bool is_col = false;
  
  const xvec_htrans<eT> Q;
  const Col<eT>&        src;
  
  inline explicit Proxy(const Op< Col< std::complex<T> >, op_htrans>& A)
    : Q  (A.m.memptr(), A.m.n_rows, A.m.n_cols)
    , src(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return 1;        }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword, const uword col) const { return Q[col]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return void_ptr(&src) == void_ptr(&X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T>
class Proxy< Op< subview_col< std::complex<T> >, op_htrans> >
  {
  public:
  
  typedef typename std::complex<T>  eT;
  
  typedef typename std::complex<T>  elem_type;
  typedef T                         pod_type;
  typedef xvec_htrans<eT>           stored_type;
  typedef const xvec_htrans<eT>&    ea_type;
  typedef const xvec_htrans<eT>&    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = true;
  static const bool is_col = false;
  
  const xvec_htrans<eT>  Q;
  const subview_col<eT>& src;
  
  inline explicit Proxy(const Op< subview_col< std::complex<T> >, op_htrans>& A)
    : Q  (A.m.colptr(0), A.m.n_rows, A.m.n_cols)
    , src(A.m)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return 1;        }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword, const uword col) const { return Q[col]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return void_ptr(&src.m) == void_ptr(&X); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T1>
class Proxy< Op<T1, op_htrans2> >
  {
  public:
  
  typedef typename T1::elem_type                           elem_type;
  typedef typename get_pod_type<elem_type>::result         pod_type;
  typedef       eOp< Op<T1, op_htrans>, eop_scalar_times>  stored_type;
  typedef const eOp< Op<T1, op_htrans>, eop_scalar_times>& ea_type;
  typedef const eOp< Op<T1, op_htrans>, eop_scalar_times>& aligned_ea_type;
  
  static const bool prefer_at_accessor = eOp< Op<T1, op_htrans>, eop_scalar_times>::prefer_at_accessor;
  static const bool has_subview        = eOp< Op<T1, op_htrans>, eop_scalar_times>::has_subview;
  static const bool fake_mat           = eOp< Op<T1, op_htrans>, eop_scalar_times>::fake_mat;
  
  // NOTE: the Op class takes care of swapping row and col for op_htrans
  static const bool is_row = eOp< Op<T1, op_htrans>, eop_scalar_times>::is_row;
  static const bool is_col = eOp< Op<T1, op_htrans>, eop_scalar_times>::is_col;
  
  arma_aligned const      Op<T1, op_htrans>                     R;
  arma_aligned const eOp< Op<T1, op_htrans>, eop_scalar_times > Q;
  
  inline explicit Proxy(const Op<T1, op_htrans2>& A)
    : R(A.m)
    , Q(R, A.aux)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.get_n_rows(); }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.get_n_cols(); }
  arma_inline uword get_n_elem() const { return Q.get_n_elem();              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return Q.P.is_alias(X); }
  
  arma_inline bool is_aligned() const { return Q.P.is_aligned(); }
  };



template<typename T1>
class Proxy< Op<T1, op_vectorise_col> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = true;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const unwrap<T1>     U;
  arma_aligned const Mat<elem_type> Q;
  
  inline explicit Proxy(const Op<T1, op_vectorise_col>& A)
    : U(A.m)
    , Q(const_cast<elem_type*>(U.M.memptr()), U.M.n_elem, 1, false, false)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row];         }
  arma_inline elem_type at_alt     (const uword i)                const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return ( void_ptr(&X) == void_ptr(&(U.M)) ); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename T1, typename T2, typename glue_type>
class Proxy< Glue<T1, T2, glue_type> >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<elem_type>                           stored_type;
  typedef const elem_type*                         ea_type;
  typedef const Mat<elem_type>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = Glue<T1, T2, glue_type>::is_row;
  static const bool is_col = Glue<T1, T2, glue_type>::is_col;
  
  arma_aligned const Mat<elem_type> Q;
  
  inline explicit Proxy(const Glue<T1, T2, glue_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }

  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT>
class Proxy< subview<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview<eT>                              stored_type;
  typedef const subview<eT>&                       ea_type;
  typedef const subview<eT>&                       aligned_ea_type;
  
  static const bool prefer_at_accessor = true;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  arma_aligned const subview<eT>& Q;
  
  inline explicit Proxy(const subview<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q[i];           }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT>
class Proxy< subview_col<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview_col<eT>                          stored_type;
  typedef const eT*                                ea_type;
  typedef const subview_col<eT>&                   aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_col<eT>& Q;
  
  inline explicit Proxy(const subview_col<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];        }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row];      }
  arma_inline elem_type at_alt     (const uword i)                const { return Q.at_alt(i); }
  
  arma_inline         ea_type         get_ea() const { return Q.colmem; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;        }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.colmem); }
  };



template<typename eT>
class Proxy< subview_row<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview_row<eT>                          stored_type;
  typedef const subview_row<eT>&                   ea_type;
  typedef const subview_row<eT>&                   aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = true;
  static const bool is_col = false;
  
  arma_aligned const subview_row<eT>& Q;
  
  inline explicit Proxy(const subview_row<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return 1;        }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword, const uword col) const { return Q[col]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT>
class Proxy< subview_row_strans<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview_row_strans<eT>                   stored_type;
  typedef const subview_row_strans<eT>&            ea_type;
  typedef const subview_row_strans<eT>&            aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_row_strans<eT>& Q;
  
  inline explicit Proxy(const subview_row_strans<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.sv_row.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT>
class Proxy< subview_row_htrans<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview_row_htrans<eT>                   stored_type;
  typedef const subview_row_htrans<eT>&            ea_type;
  typedef const subview_row_htrans<eT>&            aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_row_htrans<eT>& Q;
  
  inline explicit Proxy(const subview_row_htrans<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];   }
  arma_inline elem_type at         (const uword row, const uword) const { return Q[row]; }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];   }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.sv_row.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT, bool do_conj>
class Proxy< xtrans_mat<eT, do_conj> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Mat<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  arma_aligned const Mat<eT> Q;
  
  inline explicit Proxy(const xtrans_mat<eT, do_conj>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];          }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row,col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);   }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT>
class Proxy< xvec_htrans<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Mat<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  arma_aligned const Mat<eT> Q;
  
  inline explicit Proxy(const xvec_htrans<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];          }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row,col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);   }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT, typename T1>
class Proxy< subview_elem1<eT,T1> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef subview_elem1<eT,T1>                     stored_type;
  typedef const Proxy< subview_elem1<eT,T1> >&     ea_type;
  typedef const Proxy< subview_elem1<eT,T1> >&     aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const subview_elem1<eT,T1>& Q;
  arma_aligned const Proxy<T1>             R;
  
  inline explicit Proxy(const subview_elem1<eT,T1>& A)
    : Q(A)
    , R(A.a.get_ref())
    {
    arma_extra_debug_sigprint();
    
    const bool R_is_vec   = ((R.get_n_rows() == 1) || (R.get_n_cols() == 1));
    const bool R_is_empty = (R.get_n_elem() == 0);
    
    arma_debug_check( ((R_is_vec == false) && (R_is_empty == false)), "Mat::elem(): given object is not a vector" );
    }
  
  arma_inline uword get_n_rows() const { return R.get_n_elem(); }
  arma_inline uword get_n_cols() const { return 1;              }
  arma_inline uword get_n_elem() const { return R.get_n_elem(); }
  
  arma_inline elem_type operator[] (const uword i)                const { const uword ii = (Proxy<T1>::prefer_at_accessor) ? R.at(i,  0) : R[i  ]; arma_debug_check( (ii >= Q.m.n_elem), "Mat::elem(): index out of bounds" ); return Q.m[ii]; }
  arma_inline elem_type at         (const uword row, const uword) const { const uword ii = (Proxy<T1>::prefer_at_accessor) ? R.at(row,0) : R[row]; arma_debug_check( (ii >= Q.m.n_elem), "Mat::elem(): index out of bounds" ); return Q.m[ii]; }
  arma_inline elem_type at_alt     (const uword i)                const { const uword ii = (Proxy<T1>::prefer_at_accessor) ? R.at(i,  0) : R[i  ]; arma_debug_check( (ii >= Q.m.n_elem), "Mat::elem(): index out of bounds" ); return Q.m[ii]; }
  
  arma_inline         ea_type         get_ea() const { return (*this); }
  arma_inline aligned_ea_type get_aligned_ea() const { return (*this); }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return ( (void_ptr(&X) == void_ptr(&(Q.m))) || (R.is_alias(X)) ); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT, typename T1, typename T2>
class Proxy< subview_elem2<eT,T1,T2> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef Mat<eT>                                  stored_type;
  typedef const eT*                                ea_type;
  typedef const Mat<eT>&                           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = false;
  
  arma_aligned const Mat<eT> Q;
  
  inline explicit Proxy(const subview_elem2<eT,T1,T2>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename eT>
class Proxy< diagview<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef diagview<eT>                             stored_type;
  typedef const diagview<eT>&                      ea_type;
  typedef const diagview<eT>&                      aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = true;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const diagview<eT>& Q;
  
  inline explicit Proxy(const diagview<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];         }
  arma_inline elem_type at         (const uword row, const uword) const { return Q.at(row, 0); }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];         }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (void_ptr(&(Q.m)) == void_ptr(&X)); }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename eT>
class Proxy< spdiagview<eT> >
  {
  public:
  
  typedef eT                                       elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef spdiagview<eT>                           stored_type;
  typedef const spdiagview<eT>&                    ea_type;
  typedef const spdiagview<eT>&                    aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = false;
  static const bool is_col = true;
  
  arma_aligned const spdiagview<eT>& Q;
  
  inline explicit Proxy(const spdiagview<eT>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return Q.n_rows; }
  arma_inline uword get_n_cols() const { return 1;        }
  arma_inline uword get_n_elem() const { return Q.n_elem; }
  
  arma_inline elem_type operator[] (const uword i)                const { return Q[i];         }
  arma_inline elem_type at         (const uword row, const uword) const { return Q.at(row, 0); }
  arma_inline elem_type at_alt     (const uword i)                const { return Q[i];         }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return false; }
  };



template<typename T1, typename eop_type>
class Proxy< eOp<T1, eop_type > >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef eOp<T1, eop_type>                        stored_type;
  typedef const eOp<T1, eop_type>&                 ea_type;
  typedef const eOp<T1, eop_type>&                 aligned_ea_type;
  
  static const bool prefer_at_accessor = eOp<T1, eop_type>::prefer_at_accessor;
  static const bool has_subview        = eOp<T1, eop_type>::has_subview;
  static const bool fake_mat           = eOp<T1, eop_type>::fake_mat;
  
  static const bool is_row = eOp<T1, eop_type>::is_row;
  static const bool is_col = eOp<T1, eop_type>::is_col;
  
  arma_aligned const eOp<T1, eop_type>& Q;
  
  inline explicit Proxy(const eOp<T1, eop_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.get_n_rows(); }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.get_n_cols(); }
  arma_inline uword get_n_elem() const { return Q.get_n_elem();              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return Q.P.is_alias(X); }
  
  arma_inline bool is_aligned() const { return Q.P.is_aligned(); }
  };



template<typename T1, typename T2, typename eglue_type>
class Proxy< eGlue<T1, T2, eglue_type > >
  {
  public:
  
  typedef typename T1::elem_type                   elem_type;
  typedef typename get_pod_type<elem_type>::result pod_type;
  typedef eGlue<T1, T2, eglue_type>                stored_type;
  typedef const eGlue<T1, T2, eglue_type>&         ea_type;
  typedef const eGlue<T1, T2, eglue_type>&         aligned_ea_type;
  
  static const bool prefer_at_accessor = eGlue<T1, T2, eglue_type>::prefer_at_accessor;
  static const bool has_subview        = eGlue<T1, T2, eglue_type>::has_subview;
  static const bool fake_mat           = eGlue<T1, T2, eglue_type>::fake_mat;
  
  static const bool is_row = eGlue<T1, T2, eglue_type>::is_row;
  static const bool is_col = eGlue<T1, T2, eglue_type>::is_col;
  
  arma_aligned const eGlue<T1, T2, eglue_type>& Q;
  
  inline explicit Proxy(const eGlue<T1, T2, eglue_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.get_n_rows(); }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.get_n_cols(); }
  arma_inline uword get_n_elem() const { return Q.get_n_elem();              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];           }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row, col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);    }
  
  arma_inline         ea_type         get_ea() const { return Q; }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q; }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>& X) const { return (Q.P1.is_alias(X) || Q.P2.is_alias(X)); }
  
  arma_inline bool is_aligned() const { return (Q.P1.is_aligned() && Q.P2.is_aligned()); }
  };



template<typename out_eT, typename T1, typename op_type>
class Proxy< mtOp<out_eT, T1, op_type> >
  {
  public:
  
  typedef          out_eT                       elem_type;
  typedef typename get_pod_type<out_eT>::result pod_type;
  typedef          Mat<out_eT>                  stored_type;
  typedef          const elem_type*             ea_type;
  typedef          const Mat<out_eT>&           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = mtOp<out_eT, T1, op_type>::is_row;
  static const bool is_col = mtOp<out_eT, T1, op_type>::is_col;
  
  arma_aligned const Mat<out_eT> Q;
  
  inline explicit Proxy(const mtOp<out_eT, T1, op_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];          }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row,col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);   }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



template<typename out_eT, typename T1, typename T2, typename glue_type>
class Proxy< mtGlue<out_eT, T1, T2, glue_type > >
  {
  public:
  
  typedef          out_eT                       elem_type;
  typedef typename get_pod_type<out_eT>::result pod_type;
  typedef          Mat<out_eT>                  stored_type;
  typedef          const elem_type*             ea_type;
  typedef          const Mat<out_eT>&           aligned_ea_type;
  
  static const bool prefer_at_accessor = false;
  static const bool has_subview        = false;
  static const bool fake_mat           = false;
  
  static const bool is_row = mtGlue<out_eT, T1, T2, glue_type>::is_row;
  static const bool is_col = mtGlue<out_eT, T1, T2, glue_type>::is_col;
  
  arma_aligned const Mat<out_eT> Q;
  
  inline explicit Proxy(const mtGlue<out_eT, T1, T2, glue_type>& A)
    : Q(A)
    {
    arma_extra_debug_sigprint();
    }
  
  arma_inline uword get_n_rows() const { return is_row ? 1 : Q.n_rows; }
  arma_inline uword get_n_cols() const { return is_col ? 1 : Q.n_cols; }
  arma_inline uword get_n_elem() const { return Q.n_elem;              }
  
  arma_inline elem_type operator[] (const uword i)                    const { return Q[i];          }
  arma_inline elem_type at         (const uword row, const uword col) const { return Q.at(row,col); }
  arma_inline elem_type at_alt     (const uword i)                    const { return Q.at_alt(i);   }
  
  arma_inline         ea_type         get_ea() const { return Q.memptr(); }
  arma_inline aligned_ea_type get_aligned_ea() const { return Q;          }
  
  template<typename eT2>
  arma_inline bool is_alias(const Mat<eT2>&) const { return false; }
  
  arma_inline bool is_aligned() const { return memory::is_aligned(Q.memptr()); }
  };



//! @}