Feat: modernize CMake files

.github/workflows/ci.yml

@@ -85,7 +85,7 @@ jobs:
           cd ..
           rm -rf __build
 
-      - name: Run modules tests wihtout 'import std;'
+      - name: Run modules tests without 'import std;'
         if: ${{matrix.toolset == 'clang-19'}}
         run: |
           cd ../boost-root/libs/any
@@ -218,7 +218,7 @@ jobs:
           cd ..
           rm -rf build_module
 
-      - name: Run modules tests wihtout 'import std;'
+      - name: Run modules tests without 'import std;'
         if: ${{matrix.toolset == 'msvc-14.3'}}
         shell: cmd
         run: |
@@ -243,8 +243,8 @@ jobs:
     needs: posix
     runs-on: ubuntu-latest
     steps:
-    - name: Coveralls Finished
-      uses: coverallsapp/github-action@master
-      with:
-        github-token: ${{ secrets.github_token }}
-        parallel-finished: true
+      - name: Coveralls Finished
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.github_token }}
+          parallel-finished: true

CMakeLists.txt

@@ -2,39 +2,82 @@
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required( VERSION 3.5...3.31 )
-project( boost_any VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX )
+cmake_minimum_required(VERSION 3.21...4.2)
 
-if (BOOST_USE_MODULES)
+project(boost_any VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
+
+if(PROJECT_IS_TOP_LEVEL)
+    find_package(Boost 1.90.0 CONFIG)
+endif()
+
+if(BOOST_USE_MODULES)
+    if(NOT DEFINED CMAKE_CXX_STANDARD)
+        set(CMAKE_CXX_STANDARD 20)
+    endif()
     add_library(boost_any)
-    target_sources(boost_any PUBLIC
-        FILE_SET modules_public TYPE CXX_MODULES FILES
-            ${CMAKE_CURRENT_LIST_DIR}/modules/boost_any.cppm
+    target_sources(
+        boost_any
+        PUBLIC
+            FILE_SET modules_public
+                TYPE CXX_MODULES
+                FILES modules/boost_any.cppm
     )
 
     target_compile_features(boost_any PUBLIC cxx_std_20)
     target_compile_definitions(boost_any PUBLIC BOOST_USE_MODULES)
-    if (CMAKE_CXX_COMPILER_IMPORT_STD)
+    if(${CMAKE_CXX_STANDARD} IN_LIST CMAKE_CXX_COMPILER_IMPORT_STD)
+        set(CMAKE_CXX_MODULE_STD ON)
         target_compile_definitions(boost_any PRIVATE BOOST_ANY_USE_STD_MODULE)
         message(STATUS "Using `import std;`")
     else()
-        message(STATUS "`import std;` is not available")
+        message(WARNING "`import std;` is not available")
     endif()
     set(__scope PUBLIC)
 else()
+    set(CMAKE_VERIFY_INTERFACE_HEADER_SETS ${PROJECT_IS_TOP_LEVEL})
     add_library(boost_any INTERFACE)
     set(__scope INTERFACE)
 endif()
 
-target_include_directories(boost_any ${__scope} include)
-target_link_libraries( boost_any
-    ${__scope}
-        Boost::config
-        Boost::throw_exception
-        Boost::type_index
-)
+if(CMAKE_VERSION VERSION_LESS 3.23)
+    target_include_directories(boost_any ${__scope} include)
+else()
+    target_sources(
+        boost_any
+        ${__scope}
+        FILE_SET headers_public
+        TYPE HEADERS
+        BASE_DIRS include
+        FILES
+            include/boost/any/bad_any_cast.hpp
+            include/boost/any/basic_any.hpp
+            include/boost/any/fwd.hpp
+            include/boost/any/unique_any.hpp
+            include/boost/any/detail/config.hpp
+            include/boost/any/detail/placeholder.hpp
+    )
+    if(NOT BOOST_USE_MODULES)
+        target_compile_features(boost_any ${__scope} cxx_std_17)
+    endif()
+endif()
+
+if(PROJECT_IS_TOP_LEVEL)
+    target_link_libraries(
+        boost_any
+        ${__scope}
+            Boost::headers
+    )
+else()
+    target_link_libraries(
+        boost_any
+        ${__scope}
+            Boost::config
+            Boost::throw_exception
+            Boost::type_index
+    )
+endif()
 
-add_library( Boost::any ALIAS boost_any )
+add_library(Boost::any ALIAS boost_any)
 
 if(BUILD_TESTING)
     add_subdirectory(test)

include/boost/any/fwd.hpp

@@ -17,6 +17,9 @@
 #ifdef BOOST_HAS_PRAGMA_ONCE
 # pragma once
 #endif
+
+#include <type_traits>
+
 #endif  // #ifndef BOOST_ANY_INTERFACE_UNIT
 
 /// \file boost/any/fwd.hpp

modules/boost_any.cppm

@@ -11,7 +11,8 @@ module;
 #include <boost/assert.hpp>
 #include <boost/config.hpp>
 #include <boost/throw_exception.hpp>
-#include <boost/type_index.hpp>
+
+import boost.type_index;
 
 #ifdef BOOST_ANY_USE_STD_MODULE
 import std;

modules/usage_sample.cpp

@@ -7,10 +7,50 @@
 // clang++ -std=c++20 -fmodule-file=type_index.pcm type_index.pcm usage_sample.cpp
 
 //[any_module_example
+
+#ifdef BOOST_ANY_USE_STD_MODULE
+import std;
+#else
+# include <iostream>
+# include <sstream>
+# include <string>
+#endif
+
 import boost.any;
 
-int main() {
-    boost::any a = 42;
+namespace {
+
+    template <typename... Ts> auto any_to_string(const boost::any& a) -> std::string {
+        std::ostringstream oss;
+
+        auto try_cast = [&](auto* dummy) -> bool {
+            using T = std::decay_t<decltype(*dummy)>;
+            if (a.type() == typeid(T)) {
+                oss << boost::any_cast<T>(a);
+                return true;
+            }
+            return false;
+        };
+
+        // Expand over Ts...
+        bool const success = (try_cast((Ts*)nullptr) || ...);
+
+        if (!success) {
+            oss << "<unknown type: " << a.type().name() << ">";
+        }
+        return oss.str();
+    }
+
+}  // namespace
+
+// Usage:
+auto main() -> int {
+    boost::any const a = 42;
+#ifdef BOOST_ANY_USE_STD_MODULE
+    std::println(stdout, "{}", any_to_string<int, double, std::string>(a));
+#else
+    std::cout << any_to_string<int, double, std::string>(a) << '\n';
+#endif
 }
 //]
 

test/cmake_subdir_test/CMakeLists.txt

@@ -2,7 +2,7 @@
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5...4.0)
+cmake_minimum_required(VERSION 3.21...4.2)
 
 project(any_subdir_test LANGUAGES CXX)
 
@@ -24,8 +24,8 @@ add_subdirectory(../../ boostorg/any)
 
 enable_testing()
 
-if (BOOST_USE_MODULES)
-    add_executable(boost_any_module_usage ../modules/usage_sample.cpp)
+if(BOOST_USE_MODULES)
+    add_executable(boost_any_module_usage ../../modules/usage_sample.cpp)
     target_link_libraries(boost_any_module_usage PRIVATE Boost::any)
     add_test(NAME boost_any_module_usage COMMAND boost_any_module_usage)
 endif()
@@ -47,10 +47,10 @@ list(APPEND RUN_TESTS_SOURCES
     # any_test.cpp  # Ambiguous with modules, because all the anys now available
 )
 
-foreach (testsourcefile ${RUN_TESTS_SOURCES})
+foreach(testsourcefile ${RUN_TESTS_SOURCES})
     get_filename_component(testname ${testsourcefile} NAME_WLE)
     add_executable(${PROJECT_NAME}_${testname} ../${testsourcefile})
-    target_link_libraries(${PROJECT_NAME}_${testname} Boost::any)
+    target_link_libraries(${PROJECT_NAME}_${testname} Boost::any Boost::core)
     add_test(NAME ${PROJECT_NAME}_${testname} COMMAND ${PROJECT_NAME}_${testname})
 endforeach()