From 1c477a3e83660bfd9ade8e6fa0971d4ff7f7dc19 Mon Sep 17 00:00:00 2001
From: conrad <conrad@localhost.localdomain>
Date: Mon, 14 Mar 2022 15:22:18 +1000
Subject: [PATCH] more code to support __cpp_multidimensional_subscript

---
 include/armadillo_bits/Cube_bones.hpp  | 10 +++++
 include/armadillo_bits/Cube_meat.hpp   | 60 ++++++++++++++++++++++++++
 include/armadillo_bits/SpMat_bones.hpp |  8 ++++
 include/armadillo_bits/SpMat_meat.hpp  | 26 +++++++++++
 include/armadillo_bits/field_bones.hpp | 12 +++++-
 include/armadillo_bits/field_meat.hpp  | 56 ++++++++++++++++++++++++
 6 files changed, 171 insertions(+), 1 deletion(-)

diff --git a/include/armadillo_bits/Cube_bones.hpp b/include/armadillo_bits/Cube_bones.hpp
index bd4518a8..4e4a6926 100644
--- a/include/armadillo_bits/Cube_bones.hpp
+++ b/include/armadillo_bits/Cube_bones.hpp
@@ -271,6 +271,11 @@ class Cube : public BaseCube< eT, Cube<eT> >
   arma_inline arma_warn_unused       eT& operator() (const uword i);
   arma_inline arma_warn_unused const eT& operator() (const uword i) const;
   
+  #if defined(__cpp_multidimensional_subscript)
+  arma_inline arma_warn_unused       eT& operator[] (const uword in_row, const uword in_col, const uword in_slice);
+  arma_inline arma_warn_unused const eT& operator[] (const uword in_row, const uword in_col, const uword in_slice) const;
+  #endif
+  
   arma_inline arma_warn_unused       eT& at         (const uword in_row, const uword in_col, const uword in_slice);
   arma_inline arma_warn_unused const eT& at         (const uword in_row, const uword in_col, const uword in_slice) const;
   
@@ -490,6 +495,11 @@ class Cube<eT>::fixed : public Cube<eT>
   arma_inline arma_warn_unused       eT& operator() (const uword i);
   arma_inline arma_warn_unused const eT& operator() (const uword i) const;
   
+  #if defined(__cpp_multidimensional_subscript)
+  arma_inline arma_warn_unused       eT& operator[] (const uword in_row, const uword in_col, const uword in_slice);
+  arma_inline arma_warn_unused const eT& operator[] (const uword in_row, const uword in_col, const uword in_slice) const;
+  #endif
+  
   arma_inline arma_warn_unused       eT& at         (const uword in_row, const uword in_col, const uword in_slice);
   arma_inline arma_warn_unused const eT& at         (const uword in_row, const uword in_col, const uword in_slice) const;
   
diff --git a/include/armadillo_bits/Cube_meat.hpp b/include/armadillo_bits/Cube_meat.hpp
index ba85818c..252fc933 100644
--- a/include/armadillo_bits/Cube_meat.hpp
+++ b/include/armadillo_bits/Cube_meat.hpp
@@ -3456,6 +3456,34 @@ Cube<eT>::operator() (const uword in_row, const uword in_col, const uword in_sli
 
 
 
+#if defined(__cpp_multidimensional_subscript)
+  
+  //! element accessor; no bounds check
+  template<typename eT>
+  arma_inline
+  arma_warn_unused
+  eT&
+  Cube<eT>::operator[] (const uword in_row, const uword in_col, const uword in_slice)
+    {
+    return access::rw( mem[in_slice*n_elem_slice + in_col*n_rows + in_row] );
+    }
+  
+  
+  
+  //! element accessor; no bounds check
+  template<typename eT>
+  arma_inline
+  arma_warn_unused
+  const eT&
+  Cube<eT>::operator[] (const uword in_row, const uword in_col, const uword in_slice) const
+    {
+    return mem[in_slice*n_elem_slice + in_col*n_rows + in_row];
+    }
+  
+#endif
+
+
+
 //! element accessor; no bounds check
 template<typename eT>
 arma_inline
@@ -5409,6 +5437,38 @@ Cube<eT>::fixed<fixed_n_rows, fixed_n_cols, fixed_n_slices>::operator() (const u
 
 
 
+#if defined(__cpp_multidimensional_subscript)
+  
+  template<typename eT>
+  template<uword fixed_n_rows, uword fixed_n_cols, uword fixed_n_slices>
+  arma_inline
+  arma_warn_unused
+  eT&
+  Cube<eT>::fixed<fixed_n_rows, fixed_n_cols, fixed_n_slices>::operator[] (const uword in_row, const uword in_col, const uword in_slice)
+    {
+    const uword i = in_slice*fixed_n_elem_slice + in_col*fixed_n_rows + in_row;
+    
+    return (use_extra) ? mem_local_extra[i] : mem_local[i];
+    }
+  
+  
+  
+  template<typename eT>
+  template<uword fixed_n_rows, uword fixed_n_cols, uword fixed_n_slices>
+  arma_inline
+  arma_warn_unused
+  const eT&
+  Cube<eT>::fixed<fixed_n_rows, fixed_n_cols, fixed_n_slices>::operator[] (const uword in_row, const uword in_col, const uword in_slice) const
+    {
+    const uword i = in_slice*fixed_n_elem_slice + in_col*fixed_n_rows + in_row;
+    
+    return (use_extra) ? mem_local_extra[i] : mem_local[i];
+    }
+  
+#endif
+
+
+
 template<typename eT>
 template<uword fixed_n_rows, uword fixed_n_cols, uword fixed_n_slices>
 arma_inline
diff --git a/include/armadillo_bits/SpMat_bones.hpp b/include/armadillo_bits/SpMat_bones.hpp
index 051b8a1a..c26a9818 100644
--- a/include/armadillo_bits/SpMat_bones.hpp
+++ b/include/armadillo_bits/SpMat_bones.hpp
@@ -276,14 +276,22 @@ class SpMat : public SpBase< eT, SpMat<eT> >
   // access the i-th element; if there is nothing at element i, 0 is returned
   arma_inline arma_warn_unused SpMat_MapMat_val<eT> operator[] (const uword i);
   arma_inline arma_warn_unused eT                   operator[] (const uword i) const;
+  
   arma_inline arma_warn_unused SpMat_MapMat_val<eT> at         (const uword i);
   arma_inline arma_warn_unused eT                   at         (const uword i) const;
+  
   arma_inline arma_warn_unused SpMat_MapMat_val<eT> operator() (const uword i);
   arma_inline arma_warn_unused eT                   operator() (const uword i) const;
   
   // access the element at the given row and column; if there is nothing at that position, 0 is returned
+  #if defined(__cpp_multidimensional_subscript)
+  arma_inline arma_warn_unused SpMat_MapMat_val<eT> operator[] (const uword in_row, const uword in_col);
+  arma_inline arma_warn_unused eT                   operator[] (const uword in_row, const uword in_col) const;
+  #endif
+  
   arma_inline arma_warn_unused SpMat_MapMat_val<eT> at         (const uword in_row, const uword in_col);
   arma_inline arma_warn_unused eT                   at         (const uword in_row, const uword in_col) const;
+  
   arma_inline arma_warn_unused SpMat_MapMat_val<eT> operator() (const uword in_row, const uword in_col);
   arma_inline arma_warn_unused eT                   operator() (const uword in_row, const uword in_col) const;
   
diff --git a/include/armadillo_bits/SpMat_meat.hpp b/include/armadillo_bits/SpMat_meat.hpp
index 8c63f741..73a562c5 100644
--- a/include/armadillo_bits/SpMat_meat.hpp
+++ b/include/armadillo_bits/SpMat_meat.hpp
@@ -3326,6 +3326,32 @@ SpMat<eT>::operator()(const uword i) const
  * If there is nothing at that position, 0 is returned.
  */
 
+#if defined(__cpp_multidimensional_subscript)
+  
+  template<typename eT>
+  arma_inline
+  arma_warn_unused
+  SpMat_MapMat_val<eT>
+  SpMat<eT>::operator[] (const uword in_row, const uword in_col)
+    {
+    return SpMat_MapMat_val<eT>((*this), cache, in_row, in_col);
+    }
+  
+  
+  
+  template<typename eT>
+  arma_inline
+  arma_warn_unused
+  eT
+  SpMat<eT>::operator[] (const uword in_row, const uword in_col) const
+    {
+    return get_value(in_row, in_col);
+    }
+  
+#endif
+
+
+
 template<typename eT>
 arma_inline
 arma_warn_unused
diff --git a/include/armadillo_bits/field_bones.hpp b/include/armadillo_bits/field_bones.hpp
index 19cfb259..27c2d29d 100644
--- a/include/armadillo_bits/field_bones.hpp
+++ b/include/armadillo_bits/field_bones.hpp
@@ -97,9 +97,19 @@ class field
   arma_inline arma_warn_unused       oT& operator()(const uword i);
   arma_inline arma_warn_unused const oT& operator()(const uword i) const;
   
+  #if defined(__cpp_multidimensional_subscript)
+  arma_inline arma_warn_unused       oT& operator[](const uword row, const uword col);
+  arma_inline arma_warn_unused const oT& operator[](const uword row, const uword col) const;
+  #endif
+  
   arma_inline arma_warn_unused       oT&         at(const uword row, const uword col);
   arma_inline arma_warn_unused const oT&         at(const uword row, const uword col) const;
-
+  
+  #if defined(__cpp_multidimensional_subscript)
+  arma_inline arma_warn_unused       oT& operator[](const uword row, const uword col, const uword slice);
+  arma_inline arma_warn_unused const oT& operator[](const uword row, const uword col, const uword slice) const;
+  #endif
+  
   arma_inline arma_warn_unused       oT&         at(const uword row, const uword col, const uword slice);
   arma_inline arma_warn_unused const oT&         at(const uword row, const uword col, const uword slice) const;
   
diff --git a/include/armadillo_bits/field_meat.hpp b/include/armadillo_bits/field_meat.hpp
index 247c6dcc..d7afee37 100644
--- a/include/armadillo_bits/field_meat.hpp
+++ b/include/armadillo_bits/field_meat.hpp
@@ -601,6 +601,34 @@ field<oT>::operator() (const uword in_row, const uword in_col, const uword in_sl
 
 
 
+#if defined(__cpp_multidimensional_subscript)
+  
+  //! element accessor; no bounds check
+  template<typename oT>
+  arma_inline
+  arma_warn_unused
+  oT&
+  field<oT>::operator[] (const uword in_row, const uword in_col)
+    {
+    return (*mem[in_row + in_col*n_rows]);
+    }
+  
+  
+  
+  //! element accessor; no bounds check
+  template<typename oT>
+  arma_inline
+  arma_warn_unused
+  const oT&
+  field<oT>::operator[] (const uword in_row, const uword in_col) const
+    {
+    return (*mem[in_row + in_col*n_rows]);
+    }
+  
+#endif
+
+
+
 //! element accessor; no bounds check
 template<typename oT>
 arma_inline
@@ -625,6 +653,34 @@ field<oT>::at(const uword in_row, const uword in_col) const
 
 
 
+#if defined(__cpp_multidimensional_subscript)
+  
+  //! element accessor; no bounds check
+  template<typename oT>
+  arma_inline
+  arma_warn_unused
+  oT&
+  field<oT>::operator[] (const uword in_row, const uword in_col, const uword in_slice)
+    {
+    return (*mem[in_row + in_col*n_rows + in_slice*(n_rows*n_cols)]);
+    }
+  
+  
+  
+  //! element accessor; no bounds check
+  template<typename oT>
+  arma_inline
+  arma_warn_unused
+  const oT&
+  field<oT>::operator[] (const uword in_row, const uword in_col, const uword in_slice) const
+    {
+    return (*mem[in_row + in_col*n_rows + in_slice*(n_rows*n_cols)]);
+    }
+  
+#endif
+
+
+
 //! element accessor; no bounds check
 template<typename oT>
 arma_inline