Slicing interface

include/kwk/concepts.hpp

@@ -13,4 +13,4 @@
 #include <kwk/concepts/range.hpp>
 #include <kwk/concepts/axis.hpp>
 #include <kwk/concepts/values.hpp>
-// #include <kwk/concept/slicer.hpp>
+#include <kwk/concepts/slicer.hpp>

include/kwk/concepts/allocator.hpp

@@ -7,7 +7,7 @@
 //==================================================================================================
 #pragma once
 
-#include <concepts>
+#include <cstddef>
 
 namespace kwk::concepts
 {

include/kwk/concepts/slicer.hpp

@@ -0,0 +1,52 @@
+//======================================================================================================================
+/*
+  KIWAKU - Containers Well Made
+  Copyright : KIWAKU Project Contributors
+  SPDX-License-Identifier: BSL-1.0
+*/
+//======================================================================================================================
+#pragma once
+
+#include <kwk/concepts/extent.hpp>
+#include <kwk/concepts/values.hpp>
+#include <kwk/detail/stdfix.hpp>
+
+namespace kwk::concepts
+{
+  template<typename S>
+  inline constexpr bool is_contiguous = concepts::joker<S> || concepts::extremum <S> || std::integral<S>;
+
+  template<typename S>
+  requires( requires { S::has_step; } )
+  inline constexpr bool is_contiguous<S>  = !S::has_step;
+
+  //====================================================================================================================
+  //! @brief slicer specifier concept
+  //!
+  //! A **KIWAKU** Slicer is a type which instances can be used to compute a sub-volume of a container.
+  //====================================================================================================================
+  template<typename S>
+  concept slicer = requires(S const& s)
+  {
+    { origin  (shape<_>{} , s)                  };
+    { reindex (shape<_>{} , s, kumi::index<0>)  };
+    { reshape (shape<_>{} , s, kumi::index<0>)  };
+    { restride(stride<_>{}, s, kumi::index<0>)  };
+  };
+
+
+  //====================================================================================================================
+  //! @brief slicer specifier with unit step concept
+  //!
+  //! A kwk::unit_slicer is a type which fulfills kwk::slicer and doesn't break the contiguity of the dimension it
+  //! slices.
+  //====================================================================================================================
+  template<typename S>
+  concept unit_slicer = slicer<S> && is_contiguous<S>;
+
+  template<typename S>
+  concept interval_slicer = slicer<S> && requires(S) { typename S::kwk_is_interval; };
+
+  template<typename S>
+  concept unit_interval_slicer = interval_slicer<S> && is_contiguous<S>;
+}

include/kwk/container/container.hpp

@@ -9,6 +9,7 @@
 
 #include <kwk/algorithm/algos/for_each.hpp>
 #include <kwk/container/pick.hpp>
+#include <kwk/utility/traits/reachable.hpp>
 #include <kwk/detail/container/builder.hpp>
 #include <kwk/detail/memory/block.hpp>
 #include <type_traits>
@@ -29,8 +30,9 @@ namespace kwk
     using shape_type        = typename access_t::shape_type;
     using container_kind    = decltype(Tag);
 
-    static constexpr std::int32_t static_order  = access_t::static_order;
-    static constexpr bool         has_label     = meta_t::has_label;
+    static constexpr std::int32_t static_order          = access_t::static_order;
+    static constexpr bool         has_label             = meta_t::has_label;
+    static constexpr bool         preserve_reachability = Builder::preserve_reachability;
 
     constexpr container( container_kind ) noexcept
             : meta_t{}, data_t{}, access_t{}
@@ -44,10 +46,10 @@ namespace kwk
             : meta_t{ params }, data_t{ params }, access_t{ params }
     {}
 
-    static constexpr  auto          kind()         noexcept  { return Tag;      }
-    constexpr         std::int32_t  order() const  noexcept  { return this->shape().order(); }
-    constexpr         auto          numel() const  noexcept  { return this->shape().numel(); }
-    constexpr         bool          empty() const  noexcept  { return this->size() == 0;     }
+    static constexpr  auto  kind()        noexcept  { return Tag;                   }
+    static constexpr  auto  order()       noexcept  { return static_order;          }
+    constexpr         auto  numel() const noexcept  { return this->shape().numel(); }
+    constexpr         bool  empty() const noexcept  { return this->size() == 0;     }
 
     using meta_t::label;
 
@@ -112,29 +114,42 @@ namespace kwk
     }
 
     template<kumi::sized_product_type<static_order> Pos>
-    const_reference operator()(Pos p) const noexcept
+    decltype(auto) operator()(Pos p) const noexcept
     {
-      return kumi::apply([&](auto... i) -> const_reference { return (*this)(i...); }, p);
+      return kumi::apply([&](auto... i) -> decltype(auto) { return (*this)(i...); }, p);
     }
 
     template<kumi::sized_product_type<static_order> Pos>
-    reference operator()(Pos p) noexcept
+    decltype(auto) operator()(Pos p) noexcept
     {
-      return kumi::apply([&](auto... i) -> reference { return (*this)(i...); }, p);
+      return kumi::apply([&](auto... i) -> decltype(auto) { return (*this)(i...); }, p);
     }
 
     template<std::integral... Is>
-    requires(sizeof...(Is) == static_order) const_reference operator()(Is... is) const noexcept
+    requires(sizeof...(Is) == static_order) decltype(auto) operator()(Is... is) const noexcept
     {
       return data(static_cast<data_t const&>(*this))[ access_t::index(is...) ];
     }
 
     template<std::integral... Is>
-    requires(sizeof...(Is) == static_order) reference operator()(Is... is) noexcept
+    requires(sizeof...(Is) == static_order) decltype(auto) operator()(Is... is) noexcept
     {
       return data(static_cast<data_t&>(*this))[ access_t::index(is...) ];
     }
 
+    template<concepts::slicer... Slicers>
+    requires( (sizeof...(Slicers) <= static_order) && (!std::integral<Slicers> || ...))
+    auto operator()(Slicers... slice) const noexcept
+    {
+      auto shp = this->shape();
+      auto str = compress<sizeof...(slice)>(this->stride());
+
+      if constexpr(preserve_reachability && kwk::preserve_reachability<Slicers...>)
+        return make_view(source = this->get_data() + origin(shp, slice...), shp(slice...), str(slice...));
+      else
+        return make_view( source = this->get_data() + origin(shp, slice...), shp(slice...), str(slice...), unreachable);
+    }
+
     constexpr auto get_data() const  noexcept { return data(static_cast<data_t const&>(*this)); }
     constexpr auto get_data()        noexcept { return data(static_cast<data_t&>(*this)); }
   };

include/kwk/container/table.hpp

@@ -8,6 +8,7 @@
 #pragma once
 
 #include <kwk/container/container.hpp>
+#include <kwk/concepts/slicer.hpp>
 #include <kwk/detail/raberu.hpp>
 #include <type_traits>
 
@@ -54,7 +55,8 @@ namespace kwk
     KWK_TRIVIAL constexpr table() : parent{kwk::table_} {}
 
     /// Construct a table from a list of options
-    KWK_TRIVIAL constexpr table(rbr::concepts::option auto const&... opts) : table{rbr::settings{opts...}} {}
+    KWK_TRIVIAL constexpr table(rbr::concepts::option auto const&... opts)
+              : parent{rbr::settings{kwk::table_,opts...}} {}
 
     /// Construct a table from a settings descriptor
     KWK_TRIVIAL constexpr table(rbr::concepts::settings auto const& opts)
@@ -98,6 +100,7 @@ namespace kwk
     //==============================================================================================
     //! @}
     //==============================================================================================
+    using parent::operator();
   };
 
   //================================================================================================
@@ -121,12 +124,9 @@ namespace kwk
   //! @}
   //================================================================================================
 
-  /// Type helper
-  template<typename... Settings> struct make_table
-  {
-    using type = table<__::builder<rbr::settings(table_,Settings{}...)>>;
-  };
+  template<rbr::concepts::option... Os> auto make_table(Os const&... os) { return table{os...}; };
 
+  /// Type helper
   template<typename... Settings>
-  using make_table_t = typename make_table<Settings...>::type;
+  using make_table_t = table<__::builder<rbr::settings(table_,Settings{}...)>>;
 }

include/kwk/container/view.hpp

@@ -8,6 +8,7 @@
 #pragma once
 
 #include <kwk/container/container.hpp>
+#include <kwk/concepts/slicer.hpp>
 #include <kwk/detail/raberu.hpp>
 #include <type_traits>
 
@@ -54,7 +55,8 @@ namespace kwk
     KWK_TRIVIAL constexpr view() : parent{kwk::view_} {}
 
     /// Construct a view from a list of options
-    KWK_TRIVIAL constexpr view(rbr::concepts::option auto const&... opts) : view{rbr::settings{opts...}} {}
+    KWK_TRIVIAL constexpr view(rbr::concepts::option auto const&... opts)
+              : parent{rbr::settings{kwk::view_,opts...}} {}
 
     /// Construct a view from a settings descriptor
     KWK_TRIVIAL constexpr view(rbr::concepts::settings auto const& opts)
@@ -79,6 +81,7 @@ namespace kwk
     //==============================================================================================
     //! @}
     //==============================================================================================
+    using parent::operator();
   };
 
   //================================================================================================
@@ -103,13 +106,9 @@ namespace kwk
   //================================================================================================
   //! @}
   //================================================================================================
+  template<rbr::concepts::option... Os> auto make_view(Os const&... os) { return view{os...}; };
 
   /// Type helper
-  template<typename... Settings> struct make_view
-  {
-    using type = view<__::builder<rbr::settings(view_,Settings{}...)>>;
-  };
-
   template<typename... Settings>
-  using make_view_t = typename make_view<Settings...>::type;
+  using make_view_t = view<__::builder<rbr::settings(view_,Settings{}...)>>;
 }

include/kwk/detail/algorithm/for_each.hpp

@@ -9,6 +9,7 @@
 
 #include <kwk/detail/abi.hpp>
 #include <kwk/detail/kumi.hpp>
+#include <kwk/utility/fixed.hpp>
 #include <cstddef>
 #include <utility>