Merge pull request intel#344 from elbeno/simplify-builder-meta

include/cib/builder_meta.hpp

@@ -4,12 +4,12 @@ namespace cib {
 /**
  * Describe a builder to cib.
  *
- * @tparam BuilderType
+ * @tparam Builder
  *      The initial builder type cib should use when creating a builder.
- *      This is only the initial type, the BuilderType::add(...) function
+ *      This is only the initial type, the Builder::add(...) function
  *      may return a different type and cib will track that correctly.
  *
- * @tparam InterfaceType
+ * @tparam Interface
  *      The type-erased interface services built with this builder
  *      will implement. For example, cib::callback allows many other
  *      callables to get executed when its service gets invoked. The
@@ -19,8 +19,14 @@ namespace cib {
  *
  * @example cib::callback_meta
  */
-template <typename BuilderType, typename InterfaceType> struct builder_meta {
-    auto builder() -> BuilderType;
-    auto interface() -> InterfaceType;
+template <typename Builder, typename Interface> struct builder_meta {
+    using builder_t = Builder;
+    using interface_t = Interface;
 };
+
+template <typename BuilderMeta>
+using builder_t = typename BuilderMeta::builder_t;
+
+template <typename BuilderMeta>
+using interface_t = typename BuilderMeta::interface_t;
 } // namespace cib

include/cib/built.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <cib/detail/builder_traits.hpp>
+#include <cib/builder_meta.hpp>
 
 namespace cib {
 /**
@@ -11,5 +11,5 @@ namespace cib {
  *
  * @see cib::builder_meta
  */
-template <typename ServiceMeta> traits::interface_t<ServiceMeta> service;
+template <typename ServiceMeta> interface_t<ServiceMeta> service;
 } // namespace cib

include/cib/config.hpp

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <cib/builder_meta.hpp>
-#include <cib/detail/builder_traits.hpp>
 #include <cib/detail/compiler.hpp>
 #include <cib/detail/components.hpp>
 #include <cib/detail/conditional.hpp>

include/cib/detail/extend.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <cib/detail/builder_traits.hpp>
+#include <cib/builder_meta.hpp>
 #include <cib/detail/compiler.hpp>
 #include <cib/detail/config_item.hpp>
 #include <cib/tuple.hpp>
@@ -9,7 +9,7 @@ namespace cib::detail {
 template <typename ServiceType, typename... Args>
 struct extend : public config_item {
     using service_type = ServiceType;
-    constexpr static auto builder = cib::traits::builder_v<service_type>;
+    constexpr static auto builder = cib::builder_t<service_type>{};
     cib::tuple<Args...> args_tuple;
 
     CIB_CONSTEVAL explicit extend(Args const &...args) : args_tuple{args...} {}

test/cib/builder_meta.cpp

@@ -1,19 +1,20 @@
-#include <cib/cib.hpp>
+#include <cib/builder_meta.hpp>
 
 #include <catch2/catch_test_macros.hpp>
 
 #include <type_traits>
 
-struct TestBuilderTag {};
-struct TestInterfaceTag {};
+namespace {
+struct TestBuilderTag;
+struct TestInterfaceTag;
 
 struct test_builder_meta
     : public cib::builder_meta<TestBuilderTag, TestInterfaceTag> {};
+} // namespace
 
 TEST_CASE(
     "builder_meta builder and interface type traits return correct values") {
-    REQUIRE(std::is_same_v<TestBuilderTag,
-                           cib::traits::builder_t<test_builder_meta>>);
-    REQUIRE(std::is_same_v<TestInterfaceTag,
-                           cib::traits::interface_t<test_builder_meta>>);
+    REQUIRE(std::is_same_v<TestBuilderTag, cib::builder_t<test_builder_meta>>);
+    REQUIRE(
+        std::is_same_v<TestInterfaceTag, cib::interface_t<test_builder_meta>>);
 }

test/cib/callback.cpp

@@ -10,13 +10,13 @@ template <typename BuilderValue> constexpr static auto build() {
 
 template <typename BuilderMeta, typename BuiltCallback>
 constexpr static bool built_is_convertable_to_interface(BuiltCallback) {
-    using interface_type = cib::traits::interface_t<BuilderMeta>;
+    using interface_type = cib::interface_t<BuilderMeta>;
     return std::is_convertible_v<BuiltCallback, interface_type>;
 }
 
 struct EmptyCallbackNoArgs {
     using meta = cib::callback_meta<>;
-    constexpr static auto value = cib::traits::builder_t<meta>{};
+    constexpr static auto value = cib::builder_t<meta>{};
 };
 
 TEST_CASE("empty callback with no args", "[callback]") {
@@ -35,7 +35,7 @@ template <int Id> static bool is_callback_invoked = false;
 struct CallbackNoArgsWithSingleExtension {
     using meta = cib::callback_meta<>;
     constexpr static auto value = []() {
-        auto const builder = cib::traits::builder_t<meta>{};
+        auto const builder = cib::builder_t<meta>{};
         return builder.add([]() { is_callback_invoked<0> = true; });
     }();
 };
@@ -66,7 +66,7 @@ struct CallbackNoArgsWithMultipleExtensions {
     };
 
     constexpr static auto value = []() {
-        auto const builder = cib::traits::builder_t<meta>{};
+        auto const builder = cib::builder_t<meta>{};
 
         return builder.add([]() { is_callback_invoked<0> = true; })
             .add(extension_one)
@@ -97,7 +97,7 @@ TEST_CASE("callback with no args with multiple extensions", "[callback]") {
 
 struct CallbackWithArgsWithNoExtensions {
     using meta = cib::callback_meta<int, bool>;
-    constexpr static auto value = cib::traits::builder_t<meta>{};
+    constexpr static auto value = cib::builder_t<meta>{};
 };
 
 TEST_CASE("callback with args with no extensions", "[callback]") {
@@ -128,7 +128,7 @@ struct CallbackWithArgsWithMultipleExtensions {
     };
 
     constexpr static auto value = []() {
-        auto const builder = cib::traits::builder_t<meta>{};
+        auto const builder = cib::builder_t<meta>{};
 
         return builder
             .add([](int a, bool b) {