replace detail::disjoint_subset with set_difference

Change-Id: I0580efc61146d808ccf94edb283d95398a17a624
oliverlee · Sep 29, 2024 · 0d87890 · 0d87890
1 parent 4975653
commit 0d87890
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Showing 6 changed files with 21 additions and 109 deletions.
diff --git a/rigid_geometric_algebra/BUILD.bazel b/rigid_geometric_algebra/BUILD.bazel
@@ -29,7 +29,6 @@ cc_library(
         "detail/derive_subtraction.hpp",
         "detail/derive_vector_space_operations.hpp",
         "detail/derive_zero_constant_overload.hpp",
-        "detail/disjoint_subset.hpp",
         "detail/even.hpp",
         "detail/has_type.hpp",
         "detail/has_value.hpp",

diff --git a/rigid_geometric_algebra/blade_complement_type.hpp b/rigid_geometric_algebra/blade_complement_type.hpp
@@ -1,12 +1,16 @@
 #pragma once
 
+#include "rigid_geometric_algebra/algebra_dimension.hpp"
+#include "rigid_geometric_algebra/algebra_type.hpp"
 #include "rigid_geometric_algebra/blade_type_from.hpp"
-#include "rigid_geometric_algebra/detail/disjoint_subset.hpp"
+#include "rigid_geometric_algebra/canonical_type.hpp"
 #include "rigid_geometric_algebra/is_blade.hpp"
 
+#include <algorithm>
+#include <array>
 #include <cstddef>
+#include <ranges>
 #include <type_traits>
-#include <utility>
 
 namespace rigid_geometric_algebra {
 namespace detail {
@@ -15,18 +19,21 @@ template <bool, class>
 struct blade_complement_type_
 {};
 
-template <
-    template <class, std::size_t...> class blade_,
-    class A,
-    std::size_t... Is>
-struct blade_complement_type_<true, blade_<A, Is...>>
+template <class B>
+struct blade_complement_type_<true, B>
 {
-  static constexpr auto complement_dimensions =
-      []<std::size_t... Js>(std::index_sequence<Js...>) {
-        return detail::disjoint_subset(Is..., Js...);
-      }(std::make_index_sequence<algebra_dimension_v<A>>{});
+  using A = algebra_type_t<B>;
 
-  using type = blade_type_from_dimensions_t<A, complement_dimensions>;
+  using type = blade_type_from_dimensions_t<A, [] {
+    auto missing = std::array<std::size_t, algebra_dimension_v<A> - B::grade>{};
+
+    std::ranges::set_difference(
+        std::views::iota(0UZ, algebra_dimension_v<A>),
+        canonical_type_t<B>::dimensions,
+        missing.begin());
+
+    return missing;
+  }()>;
 };
 
 }  // namespace detail

diff --git a/rigid_geometric_algebra/detail/disjoint_subset.hpp b/rigid_geometric_algebra/detail/disjoint_subset.hpp
diff --git a/test/blade_type_from_test.cpp b/test/blade_type_from_test.cpp
@@ -58,7 +58,7 @@ auto main() -> int
         same<G2::blade<>, blade_type_from_dimensions_t<G2, {}>>() and
         same<G2::blade<0>, blade_type_from_dimensions_t<G2, {0}>>() and
         same<G2::blade<1, 2>, blade_type_from_dimensions_t<G2, {1, 2}>>() and
-        same<G2::blade<2, 1, 0>, blade_type_from_dimensions_t<G2, {2, 1, 0}>>()
-    );
+        same<G2::blade<2, 1, 0>,
+             blade_type_from_dimensions_t<G2, {2, 1, 0}>>());
   };
 }
diff --git a/test/detail/BUILD.bazel b/test/detail/BUILD.bazel
@@ -75,16 +75,6 @@ cc_test(
     ],
 )
 
-cc_test(
-    name = "disjoint_subset_test",
-    size = "small",
-    srcs = ["disjoint_subset_test.cpp"],
-    deps = [
-        "//rigid_geometric_algebra",
-        "@skytest",
-    ],
-)
-
 cc_test(
     name = "has_type_test",
     size = "small",

diff --git a/test/detail/disjoint_subset_test.cpp b/test/detail/disjoint_subset_test.cpp