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pylene/include/mln/core/image/private/filtered.hpp

-#pragma once
-
-#include <mln/core/image/private/image_traits.hpp>
-#include <mln/core/rangev3/view/filter.hpp>
-
-#include <range/v3/begin_end.hpp>
-#include <range/v3/empty.hpp>
-
-#include <utility>
-
-namespace mln::detail
-{
-
-
-  template <typename I, typename F>
-  struct filtered
-  {
-    using value_type = image_value_t<I>;
-    using reference  = image_reference_t<I>;
-
-    filtered(I ima, F f)
-      : rng_(mln::ranges::view::filter(ima.domain(), f))
-      , ima_(ima)
-      , f_(f)
-    {
-    }
-
-    auto begin() { return ::ranges::begin(rng_); }
-    auto end() { return ::ranges::end(rng_); }
-
-    bool has(value_type p) const { return f_(ima_(p)); }
-    bool empty() const { return ::ranges::empty(rng_); }
-
-  private:
-    using rng_t = decltype(mln::ranges::view::filter(std::declval<I>().domain(), std::declval<F>()));
-
-    rng_t rng_;
-    I     ima_;
-    F     f_;
-  };
-
-} // namespace mln::detail

pylene/include/mln/core/image/view/filter.hpp

 #pragma once
 
 #include <mln/core/image/image.hpp>
-#include <mln/core/image/private/filtered.hpp>
 #include <mln/core/image/view/adaptor.hpp>
 #include <mln/core/rangev3/view/filter.hpp>
 
@@ -28,9 +27,36 @@ namespace mln
     using typename filter_view::image_adaptor::point_type;
     using typename filter_view::image_adaptor::reference;
     using typename filter_view::image_adaptor::value_type;
-    using domain_type = detail::filtered<I, F>;
+
+    class domain_type
+    {
+      using fun_t = ::ranges::semiregular_t<F>;
+      using rng_t = decltype(mln::ranges::view::filter(std::declval<I>().domain(), std::declval<fun_t>()));
+
+      rng_t rng_;
+      I     ima_;
+      fun_t f_;
+
+    public:
+      using value_type = image_value_t<I>;
+      using reference  = image_reference_t<I>;
+
+      domain_type(I ima, F f)
+        : rng_(mln::ranges::view::filter(ima.domain(), std::move(f)))
+        , ima_(std::move(ima))
+        , f_(std::move(f))
+      {
+      }
+
+      auto begin() { return ::ranges::begin(rng_); }
+      auto end() { return ::ranges::end(rng_); }
+
+      bool has(value_type p) const { return f_(ima_(p)); }
+      bool empty() const { return ::ranges::empty(rng_); }
+    };
     /// \}
 
+
     /// Traits & Image Properties
     /// \{
     using accessible = image_accessible_t<I>;
@@ -56,6 +82,7 @@ namespace mln
       }
     };
 
+
   public:
     filter_view(I ima, F fun)
       : filter_view::image_adaptor{std::move(ima)}
@@ -63,8 +90,8 @@ namespace mln
     {
     }
 
-    domain_type domain() const { return detail::filtered{this->base(), this->f}; }
 
+    domain_type domain() const { return {this->base(), this->f}; }
 
     auto new_values() { return mln::ranges::view::filter(this->base().new_values(), f); }
 

tests/core/image/view/filter.cpp

@@ -24,6 +24,14 @@ TEST(View, filter_readonly)
   mln::experimental::iota(ima, 0);
   auto x = mln::view::filter(ima, [](int v) { return v > 10; });
 
+#ifdef PYLENE_CONCEPT_TS_ENABLED
+  static_assert(concepts::OutputImage<decltype(x)>);
+  static_assert(concepts::ViewImage<decltype(x)>);
+  static_assert(concepts::IndexableAndAccessibleImage<decltype(x)>);
+  static_assert(not concepts::BidirectionalImage<decltype(x)>);
+  static_assert(not concepts::RawImage<decltype(x)>);
+#endif // PYLENE_CONCEPT_TS_ENABLED
+
   ASSERT_TRUE(mln::experimental::all_of(x > 10));
 
   mln_foreach_new (auto&& pix, ima.new_pixels())
@@ -50,6 +58,14 @@ TEST(View, filter_writable)
   mln::experimental::iota(ima, 0);
   auto x = mln::view::filter(ima, [](int v) { return v > 10; });
 
+#ifdef PYLENE_CONCEPT_TS_ENABLED
+  static_assert(concepts::OutputImage<decltype(x)>);
+  static_assert(concepts::ViewImage<decltype(x)>);
+  static_assert(concepts::IndexableAndAccessibleImage<decltype(x)>);
+  static_assert(not concepts::BidirectionalImage<decltype(x)>);
+  static_assert(not concepts::RawImage<decltype(x)>);
+#endif // PYLENE_CONCEPT_TS_ENABLED
+
   mln::experimental::fill(x, 10);
   ASSERT_TRUE(mln::experimental::all_of(ima <= 10));
 }
@@ -65,6 +81,14 @@ TEST(View, filter_twice)
   mln::experimental::iota(ima, 0);
   auto u = mln::view::filter(ima, [](int v) { return v > 10 && v < 15; });
 
+#ifdef PYLENE_CONCEPT_TS_ENABLED
+  static_assert(concepts::OutputImage<decltype(u)>);
+  static_assert(concepts::ViewImage<decltype(u)>);
+  static_assert(concepts::IndexableAndAccessibleImage<decltype(u)>);
+  static_assert(not concepts::BidirectionalImage<decltype(u)>);
+  static_assert(not concepts::RawImage<decltype(u)>);
+#endif // PYLENE_CONCEPT_TS_ENABLED
+
   // FIXME:
   // auto x = view::filter(ima, [](int v) { return v > 10; });
   // auto u = view::filter(x, [](int v) { return v < 15; });