update docs

Author: KRM7

.github/workflows/sanitizers.yml

@@ -16,6 +16,7 @@ jobs:
             { cxx: clang++-16, pkgs: clang-16 },
             { cxx: clang++-17, pkgs: clang-17 },
             { cxx: clang++-18, pkgs: clang-18 },
+            { cxx: clang++-19, pkgs: clang-19 },
             { cxx: g++-11, pkgs: g++-11 },
             { cxx: g++-12, pkgs: g++-12 },
             { cxx: g++-13, pkgs: g++-13 },

CMakeLists.txt

@@ -6,6 +6,7 @@ include(GNUInstallDirs)
 include(CMakePackageConfigHelpers)
 
 option(SMP_BUILD_BENCHMARKS "Build the benchmarks for the library when ON." ON)
+option(SMP_BUILD_EXAMPLES "Build the examples for the library when ON." ON)
 
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/build")
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
@@ -54,6 +55,10 @@ if(BUILD_TESTING)
     add_subdirectory("${CMAKE_CURRENT_SOURCE_DIR}/test")
 endif()
 
-if (SMP_BUILD_BENCHMARKS)
+if(SMP_BUILD_BENCHMARKS)
     add_subdirectory("${CMAKE_CURRENT_SOURCE_DIR}/benchmark")
 endif()
+
+if(SMP_BUILD_EXAMPLES)
+    add_subdirectory("${CMAKE_CURRENT_SOURCE_DIR}/example")
+endif()

README.md

@@ -0,0 +1,4 @@
+#find_package(benchmark REQUIRED)
+
+add_executable(small_unique_ptr_example "${CMAKE_CURRENT_SOURCE_DIR}/move_only_function.cpp")
+target_link_libraries(small_unique_ptr_example PRIVATE small_unique_ptr)

example/CMakeLists.txt

@@ -0,0 +1,7 @@
+#include "move_only_function.hpp"
+#include <iostream>
+
+int main() {
+    move_only_function<void()> f = [] { std::cout << "Hi\n"; };
+    f();
+}

example/move_only_function.cpp

@@ -0,0 +1,81 @@
+#ifndef MOVE_ONLY_FUNCTION_HPP
+#define MOVE_ONLY_FUNCTION_HPP
+
+#include <functional>
+#include <memory>
+#include <type_traits>
+#include <utility>
+#include <cstddef>
+#include "small_unique_ptr.hpp"
+
+template<typename...>
+class move_only_function;
+
+template<typename Ret, typename... Args>
+class move_only_function<Ret(Args...)>
+{
+public:
+    constexpr move_only_function() noexcept = default;
+    constexpr move_only_function(std::nullptr_t) noexcept {}
+
+    template<typename F>
+    requires(!std::is_same_v<std::remove_reference_t<F>, move_only_function> && std::is_invocable_r_v<Ret, F&, Args...>)
+    constexpr move_only_function(F&& f) :
+        fptr_(smp::make_unique_small<Impl<std::decay_t<F>>>(std::forward<F>(f)))
+    {}
+
+    template<typename F>
+    requires(!std::is_same_v<std::remove_reference_t<F>, move_only_function> && std::is_invocable_r_v<Ret, F&, Args...>)
+    constexpr move_only_function& operator=(F&& f)
+    {
+        fptr_ = smp::make_unique_small<Impl<std::decay_t<F>>>(std::forward<F>(f));
+        return *this;
+    }
+
+    constexpr move_only_function(move_only_function&&)            = default;
+    constexpr move_only_function& operator=(move_only_function&&) = default;
+
+    constexpr Ret operator()(Args... args) const
+    {
+        return fptr_->invoke(std::forward<Args>(args)...);
+    }
+
+    constexpr void swap(move_only_function& other) noexcept
+    {
+        fptr_.swap(other.fptr_);
+    }
+
+    constexpr explicit operator bool() const noexcept { return static_cast<bool>(fptr_); }
+
+private:
+    struct ImplBase
+    {
+        constexpr virtual Ret invoke(Args...) = 0;
+        constexpr virtual void small_unique_ptr_move(void* dst) noexcept = 0;
+        constexpr virtual ~ImplBase() = default;
+    };
+
+    template<typename Callable>
+    struct Impl : public ImplBase
+    {
+        constexpr Impl(Callable func) noexcept(std::is_nothrow_move_constructible_v<Callable>) :
+            func_(std::move(func))
+        {}
+
+        constexpr void small_unique_ptr_move(void* dst) noexcept override
+        {
+            std::construct_at(static_cast<Impl*>(dst), std::move(*this));
+        }
+
+        constexpr Ret invoke(Args... args) override
+        {
+            return std::invoke(func_, std::forward<Args>(args)...);
+        }
+
+        Callable func_;
+    };
+
+    smp::small_unique_ptr<ImplBase> fptr_ = nullptr;
+};
+
+#endif // !MOVE_ONLY_FUNCTION_HPP

example/move_only_function.hpp

@@ -42,7 +42,7 @@ namespace smp::detail
     }
 
     template<typename T>
-    concept has_virtual_move = requires(std::remove_cv_t<T> object, void* const dst)
+    concept has_virtual_move = requires(std::remove_cv_t<T>& object, void* const dst)
     {
         requires std::is_polymorphic_v<T>;
         { object.small_unique_ptr_move(dst) } noexcept -> std::same_as<void>;