Replace unsigned long with size_t to prevent loss of data

doc/source/morpho/watershed_hierarchy.rst

@@ -75,7 +75,7 @@ This example is used to generate the grayscale lena watershed hierarchy by area
         mln::image2d<uint8_t> input = ...;
 
         // Compute the watershed hierarchy by area
-        auto area_attribute_func = [](auto tree, auto node_map) -> std::vector<unsigned long> {
+        auto area_attribute_func = [](auto tree, auto node_map) -> std::vector<size_t> {
             return tree.compute_attribute_on_points(node_map, mln::accu::features::count<>());
         };
         auto [tree, node_map] = mln::morpho::watershed_hierarchy(input, area_attribute_func, mln::c4);

doc/source/snippets/watershed_hierarchy_example.cpp

@@ -13,7 +13,7 @@ template <typename V>
 void process_example(const mln::image2d<V>& img, const std::string& output_filename, const double threshold)
 {
   // 2. Build the watershed hierarchy
-  auto area_attribute_func = [](auto tree, auto nm) -> std::vector<unsigned long> {
+  auto area_attribute_func = [](auto tree, auto nm) -> std::vector<size_t> {
     return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
   };
   auto [t, nm] = mln::morpho::watershed_hierarchy(img, area_attribute_func, mln::c4);

tests/morpho/watershed_hierarchy.cpp

@@ -95,7 +95,7 @@ TEST(Morpho, AreaWatershedHierarchyGray)
 
   auto [tree, _] = mln::morpho::watershed_hierarchy(
       input,
-      [](auto tree, auto nm) -> std::vector<unsigned long> {
+      [](auto tree, auto nm) -> std::vector<size_t> {
         return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
       },
       mln::c4, [](const auto& a, const auto& b) -> float { return mln::functional::l2dist_t<>()(a, b); });
@@ -129,7 +129,7 @@ TEST(Morpho, AreaWatershedHierarchyGrayHQ)
 
   auto [tree, _] = mln::morpho::watershed_hierarchy(
       input,
-      [](auto tree, auto nm) -> std::vector<unsigned long> {
+      [](auto tree, auto nm) -> std::vector<size_t> {
         return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
       },
       mln::c4, [](const auto& a, const auto& b) -> std::uint8_t { return mln::functional::l2dist_t<>()(a, b); });
@@ -163,7 +163,7 @@ TEST(Morpho, AreaWatershedHierarchyRGB)
 
   auto [tree, _] = mln::morpho::watershed_hierarchy(
       input,
-      [](auto tree, auto nm) -> std::vector<unsigned long> {
+      [](auto tree, auto nm) -> std::vector<size_t> {
         return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
       },
       mln::c4, [](const auto& a, const auto& b) -> float { return mln::functional::l2dist_t<>()(a, b); });
@@ -197,7 +197,7 @@ TEST(Morpho, AreaWatershedHierarchyGrayC8)
 
   auto [tree, _] = mln::morpho::watershed_hierarchy(
       input,
-      [](auto tree, auto nm) -> std::vector<unsigned long> {
+      [](auto tree, auto nm) -> std::vector<size_t> {
         return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
       },
       mln::c8, [](const auto& a, const auto& b) -> float { return mln::functional::l2dist_t<>()(a, b); });
@@ -229,7 +229,7 @@ TEST(Morpho, AreaWatershedHierarchy3DImage)
 
   auto [tree, _] = mln::morpho::watershed_hierarchy(
       input,
-      [](auto tree, auto nm) -> std::vector<unsigned long> {
+      [](auto tree, auto nm) -> std::vector<size_t> {
         return tree.compute_attribute_on_points(nm, mln::accu::features::count<>());
       },
       mln::c26, [](const auto& a, const auto& b) -> float { return mln::functional::l2dist_t<>()(a, b); });