entity: move concepts out to another file

2 files changed, 104 insertions, 91 deletions

diff --git a/entity/concepts.hpp b/entity/concepts.hpp
new file mode 100644
index 00000000..46ec4f6a
--- /dev/null
+++ b/entity/concepts.hpp
@@ -0,0 +1,103 @@
+#pragma once
+#include "util.hpp"
+#include "compat/function2.hpp"
+#include <concepts>
+#include <type_traits>
+
+namespace floormat::entities {
+
+template<typename F, typename T, typename FieldType>
+concept FieldReader_memfn = requires(const T x, F f) {
+    { (x.*f)() } -> std::convertible_to<FieldType>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldReader_ptr = requires(const T x, F f) {
+    { x.*f } -> std::convertible_to<FieldType>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldReader_function = requires(const T x, F f) {
+    { f(x) } -> std::convertible_to<FieldType>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldReader = requires {
+    requires FieldReader_memfn<F, T, FieldType> ||
+             FieldReader_ptr<F, T, FieldType> ||
+             FieldReader_function<F, T, FieldType>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldWriter_memfn = requires(T x, move_qualified<FieldType> value, F f) {
+    { (x.*f)(value) } -> std::same_as<void>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldWriter_ptr = requires(T x, move_qualified<FieldType> value, F f) {
+    { x.*f = value };
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldWriter_function = requires(T x, move_qualified<FieldType> value, F f) {
+    { f(x, value) } -> std::same_as<void>;
+};
+
+template<typename F, typename T, typename FieldType>
+concept FieldWriter = requires {
+    requires FieldWriter_memfn<F, T, FieldType> ||
+             FieldWriter_ptr<F, T, FieldType> ||
+             FieldWriter_function<F, T, FieldType> ||
+             std::same_as<F, std::nullptr_t>;
+};
+
+} // namespace floormat::entities
+
+namespace floormat::entities::detail {
+
+template<typename Obj, typename Type, FieldReader<Obj, Type> R>
+struct read_field {
+    static constexpr Type read(const Obj& x, R r) { return r(x); }
+};
+
+template<typename Obj, typename Type>
+struct read_field<Obj, Type, Type (Obj::*)() const> {
+    static constexpr Type read(const Obj& x, Type (Obj::*r)() const) { return (x.*r)(); }
+};
+
+template<typename Obj, typename Type>
+struct read_field<Obj, Type, Type Obj::*> {
+    static constexpr Type read(const Obj& x, Type Obj::*r) { return x.*r; }
+};
+
+template<typename Obj, typename Type, bool Owning, bool Copyable, typename Capacity, bool Throwing, bool ExcGuarantee>
+struct read_field<Obj, Type, fu2::function_base<Owning, Copyable, Capacity, Throwing, ExcGuarantee, void(const Obj&, move_qualified<Type>) const>>
+{
+    template<typename F> static constexpr Type read(const Obj& x, F&& fun) { return fun(x); }
+};
+
+template<typename Obj, typename FieldType, FieldWriter<Obj, FieldType> W> struct write_field {
+    static constexpr void write(Obj& x, W w, move_qualified<FieldType> value) { w(x, value); }
+};
+
+template<typename Obj, typename FieldType>
+struct write_field<Obj, FieldType, void(Obj::*)(move_qualified<FieldType>)> {
+    static constexpr void write(Obj& x, void(Obj::*w)(move_qualified<FieldType>), move_qualified<FieldType> value) { (x.*w)(value); }
+};
+
+template<typename Obj, typename FieldType>
+struct write_field<Obj, FieldType, FieldType Obj::*> {
+    static constexpr void write(Obj& x, FieldType Obj::* w, move_qualified<FieldType> value) { x.*w = value; }
+};
+
+template<typename Obj, typename Type, bool Owning, bool Copyable, typename Capacity, bool Throwing, bool ExcGuarantee>
+struct write_field<Obj, Type, fu2::function_base<Owning, Copyable, Capacity, Throwing, ExcGuarantee, void(Obj&, move_qualified<Type>) const>> {
+    template<typename F> static constexpr void write(Obj& x, F&& fun, move_qualified<Type> value) { fun(x, value); }
+};
+
+template<typename Obj, typename FieldType>
+struct write_field<Obj, FieldType, std::nullptr_t> {
+    static constexpr void write(Obj&, std::nullptr_t, move_qualified<FieldType>) { fm_abort("no writing for this accessor"); }
+};
+
+} // namespace floormat::entities::detail
diff --git a/entity/metadata.hpp b/entity/metadata.hpp
index cbfcd38a..d1ecfa71 100644
--- a/entity/metadata.hpp
+++ b/entity/metadata.hpp
@@ -3,8 +3,8 @@
 #include "accessor.hpp"
 #include "constraints.hpp"
 #include "util.hpp"
+#include "concepts.hpp"
 #include <cstddef>
-#include <concepts>
 #include <type_traits>
 #include <limits>
 #include <utility>
@@ -15,98 +15,8 @@
 
 namespace floormat::entities {
 
-template<typename F, typename T, typename FieldType>
-concept FieldReader_memfn = requires(const T x, F f) {
-    { (x.*f)() } -> std::convertible_to<FieldType>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldReader_ptr = requires(const T x, F f) {
-    { x.*f } -> std::convertible_to<FieldType>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldReader_function = requires(const T x, F f) {
-    { f(x) } -> std::convertible_to<FieldType>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldReader = requires {
-    requires FieldReader_memfn<F, T, FieldType> ||
-             FieldReader_ptr<F, T, FieldType> ||
-             FieldReader_function<F, T, FieldType>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldWriter_memfn = requires(T x, move_qualified<FieldType> value, F f) {
-    { (x.*f)(value) } -> std::same_as<void>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldWriter_ptr = requires(T x, move_qualified<FieldType> value, F f) {
-    { x.*f = value };
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldWriter_function = requires(T x, move_qualified<FieldType> value, F f) {
-    { f(x, value) } -> std::same_as<void>;
-};
-
-template<typename F, typename T, typename FieldType>
-concept FieldWriter = requires {
-    requires FieldWriter_memfn<F, T, FieldType> ||
-             FieldWriter_ptr<F, T, FieldType> ||
-             FieldWriter_function<F, T, FieldType> ||
-             std::same_as<F, std::nullptr_t>;
-};
-
 namespace detail {
 
-template<typename Obj, typename Type, FieldReader<Obj, Type> R>
-struct read_field {
-    static constexpr Type read(const Obj& x, R r) { return r(x); }
-};
-
-template<typename Obj, typename Type>
-struct read_field<Obj, Type, Type (Obj::*)() const> {
-    static constexpr Type read(const Obj& x, Type (Obj::*r)() const) { return (x.*r)(); }
-};
-
-template<typename Obj, typename Type>
-struct read_field<Obj, Type, Type Obj::*> {
-    static constexpr Type read(const Obj& x, Type Obj::*r) { return x.*r; }
-};
-
-template<typename Obj, typename Type, bool Owning, bool Copyable, typename Capacity, bool Throwing, bool ExcGuarantee>
-struct read_field<Obj, Type, fu2::function_base<Owning, Copyable, Capacity, Throwing, ExcGuarantee, void(const Obj&, move_qualified<Type>) const>>
-{
-    template<typename F> static constexpr Type read(const Obj& x, F&& fun) { return fun(x); }
-};
-
-template<typename Obj, typename FieldType, FieldWriter<Obj, FieldType> W> struct write_field {
-    static constexpr void write(Obj& x, W w, move_qualified<FieldType> value) { w(x, value); }
-};
-
-template<typename Obj, typename FieldType>
-struct write_field<Obj, FieldType, void(Obj::*)(move_qualified<FieldType>)> {
-    static constexpr void write(Obj& x, void(Obj::*w)(move_qualified<FieldType>), move_qualified<FieldType> value) { (x.*w)(value); }
-};
-
-template<typename Obj, typename FieldType>
-struct write_field<Obj, FieldType, FieldType Obj::*> {
-    static constexpr void write(Obj& x, FieldType Obj::* w, move_qualified<FieldType> value) { x.*w = value; }
-};
-
-template<typename Obj, typename Type, bool Owning, bool Copyable, typename Capacity, bool Throwing, bool ExcGuarantee>
-struct write_field<Obj, Type, fu2::function_base<Owning, Copyable, Capacity, Throwing, ExcGuarantee, void(Obj&, move_qualified<Type>) const>> {
-    template<typename F> static constexpr void write(Obj& x, F&& fun, move_qualified<Type> value) { fun(x, value); }
-};
-
-template<typename Obj, typename FieldType>
-struct write_field<Obj, FieldType, std::nullptr_t> {
-    static constexpr void write(Obj&, std::nullptr_t, move_qualified<FieldType>) { fm_abort("no writing for this accessor"); }
-};
-
 template<typename F, typename Tuple, std::size_t N>
 requires std::invocable<F, decltype(std::get<N>(std::declval<Tuple>()))>
 constexpr CORRADE_ALWAYS_INLINE void visit_tuple(F&& fun, Tuple&& tuple)