more c++20 fixes

Author: BestITUserEUW

.github/workflows/linux.yaml

@@ -86,7 +86,6 @@ jobs:
           max-size: "2G"
       - name: Compile
         run: |
-          $CXX --version
           cmake -B build -G Ninja -DORYX_CRT_BUILD_TESTS=ON -DCMAKE_BUILD_TYPE=Release
           cmake --build build
       - name: Run tests

include/oryx/callback_list.hpp

@@ -17,6 +17,7 @@ template <class... Args>
 class CallbackList {
 public:
     using ID = uint64_t;
+    using Callback = std::function<void(Args...)>;
 
     static constexpr ID kIDMax = std::numeric_limits<ID>::max();
     /**
@@ -41,13 +42,11 @@ class CallbackList {
         ID id_;
     };
 
-    using Callback = std::function<void(Args...)>;
-
     CallbackList() = default;
 
     auto Subscribe(Callback&& cb) -> Handle {
         ID id = id_.fetch_add(1, std::memory_order_relaxed);
-        subs_.Apply([&](auto& subs) mutable { subs.emplace_back(id, std::forward<Callback>(cb)); });
+        subs_.Apply([&](auto& subs) { subs.emplace_back(id, std::forward<Callback>(cb)); });
         return Handle(id);
     }
 

include/oryx/lazy_component.hpp

@@ -13,7 +13,14 @@ namespace oryx {
 template <class T>
 class LazyComponent {
 public:
-    using FactoryContainer = std::move_only_function<T()>;
+#ifdef __cpp_lib_move_only_function
+    template <typename... S>
+    using FunctionType = std::move_only_function<S...>;
+#else
+    template <typename... S>
+    using FunctionType = std::function<S...>;
+#endif
+    using FactoryContainer = FunctionType<T()>;
 
     LazyComponent() = default;
 
@@ -53,7 +60,7 @@ class LazyComponent {
     }
 
     std::once_flag created_flag_{};
-    std::move_only_function<T()> factory_{};
+    FactoryContainer factory_{};
     mutable std::unique_ptr<T> value_{};
 };
 

tests/retry_test.cpp

@@ -36,7 +36,7 @@ TEST_CASE("Retryable succeeds after some tries") {
 TEST_CASE("Exhausting max retries") {
     int tries = 4;
     int tries_so_far = 0;
-    auto retryable = [&]() -> bool {
+    auto retryable = [&]() {
         tries_so_far++;
 
         if (tries_so_far == tries) {
@@ -56,14 +56,14 @@ TEST_CASE("Passing a custom predicate") {
     int tries_so_far = 0;
     int tries = 5;
 
-    auto never_succeeds = [&] -> bool {
+    auto never_succeeds = [&]() {
         if (++tries_so_far == tries) {
             flag = true;
         }
         return false;
     };
 
-    auto stopper = [&flag] -> bool { return flag; };
+    auto stopper = [&flag]() { return flag; };
     auto config = kDefaultConfig;
     config.max_retries = 10;
     CHECK_FALSE(retry::ExponentialBackoff(config, never_succeeds, stopper));
@@ -75,7 +75,7 @@ TEST_CASE("Works with stop token as expected") {
     int tries_so_far = 0;
     int tries = 5;
 
-    auto never_succeeds = [&] -> bool {
+    auto never_succeeds = [&]() {
         if (++tries_so_far == tries) {
             ssource.request_stop();
         }