for_each_type for specific kind of types

ROADMAP.md

@@ -17,7 +17,6 @@
 - `try_invoke`/`is_invocable` should return error codes
 - conan package config
 - test and support shared libraries
-- add `for_each_type` for specific kind of types
 
 ## Thoughts
 

develop/singles/headers/meta.hpp/meta_all.hpp

@@ -2556,6 +2556,7 @@ namespace meta_hpp
 
         template < detail::type_family Type >
         [[nodiscard]] bool is() const noexcept;
+        [[nodiscard]] bool is(type_kind kind) const noexcept;
 
         template < detail::type_family Type >
         [[nodiscard]] Type as() const noexcept;
@@ -4395,11 +4396,15 @@ namespace meta_hpp::detail
 
 namespace meta_hpp
 {
-    template < typename F >
+    template < detail::type_family Type = any_type, typename F >
     void for_each_type(F&& f) {
         using namespace detail;
         type_registry& registry = type_registry::instance();
-        registry.for_each_type(std::forward<F>(f));
+        registry.for_each_type([&f](const any_type& type) {
+            if ( type.is<Type>() ) {
+                std::invoke(f, type.as<Type>());
+            }
+        });
     }
 
     template < typename T >
@@ -8766,11 +8771,14 @@ namespace meta_hpp
         if constexpr ( std::is_same_v<Type, any_type> ) {
             return data_ != nullptr;
         } else {
-            constexpr type_kind is_kind{detail::type_traits<Type>::kind};
-            return data_ != nullptr && data_->kind == is_kind;
+            return is(detail::type_traits<Type>::kind);
         }
     }
 
+    [[nodiscard]] inline bool any_type::is(type_kind kind) const noexcept {
+        return data_ != nullptr && data_->kind == kind;
+    }
+
     template < detail::type_family Type >
     Type any_type::as() const noexcept {
         if constexpr ( std::is_same_v<Type, any_type> ) {

develop/untests/meta_features/for_each_type_tests.cpp

@@ -0,0 +1,46 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021-2023, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#include <meta.hpp/meta_all.hpp>
+#include <doctest/doctest.h>
+
+namespace
+{
+    class A{};
+    class B{};
+}
+
+TEST_CASE("meta/meta_features/for_each_type") {
+    namespace meta = meta_hpp;
+
+    SUBCASE("any_type") {
+        std::set<meta_hpp::any_type> all_types;
+        meta::for_each_type([&all_types](const meta::any_type& type){
+            all_types.insert(type);
+        });
+        CHECK_FALSE(all_types.contains(meta::resolve_type<A>()));
+
+        meta::for_each_type([&all_types](const meta::any_type& type){
+            all_types.insert(type);
+        });
+        CHECK(all_types.contains(meta::resolve_type<A>()));
+
+    }
+
+    SUBCASE("specific_type") {
+        std::set<meta_hpp::array_type> all_types;
+
+        meta::for_each_type<meta::array_type>([&all_types](const meta::array_type& type){
+            all_types.insert(type);
+        });
+        CHECK_FALSE(all_types.contains(meta::resolve_type<A[]>()));
+
+        meta::for_each_type<meta::array_type>([&all_types](const meta::array_type& type){
+            all_types.insert(type);
+        });
+        CHECK(all_types.contains(meta::resolve_type<A[]>()));
+    }
+}

headers/meta.hpp/meta_registry.hpp

@@ -16,11 +16,15 @@
 
 namespace meta_hpp
 {
-    template < typename F >
+    template < detail::type_family Type = any_type, typename F >
     void for_each_type(F&& f) {
         using namespace detail;
         type_registry& registry = type_registry::instance();
-        registry.for_each_type(std::forward<F>(f));
+        registry.for_each_type([&f](const any_type& type) {
+            if ( type.is<Type>() ) {
+                std::invoke(f, type.as<Type>());
+            }
+        });
     }
 
     template < typename T >

headers/meta.hpp/meta_types.hpp

@@ -151,6 +151,7 @@ namespace meta_hpp
 
         template < detail::type_family Type >
         [[nodiscard]] bool is() const noexcept;
+        [[nodiscard]] bool is(type_kind kind) const noexcept;
 
         template < detail::type_family Type >
         [[nodiscard]] Type as() const noexcept;

headers/meta.hpp/meta_types/any_type.hpp

@@ -20,11 +20,14 @@ namespace meta_hpp
         if constexpr ( std::is_same_v<Type, any_type> ) {
             return data_ != nullptr;
         } else {
-            constexpr type_kind is_kind{detail::type_traits<Type>::kind};
-            return data_ != nullptr && data_->kind == is_kind;
+            return is(detail::type_traits<Type>::kind);
         }
     }
 
+    [[nodiscard]] inline bool any_type::is(type_kind kind) const noexcept {
+        return data_ != nullptr && data_->kind == kind;
+    }
+
     template < detail::type_family Type >
     Type any_type::as() const noexcept {
         if constexpr ( std::is_same_v<Type, any_type> ) {