samples/windll: simplify to pure exe-exports-int / DLL-imports-int

Remove all openmethod references. The example now demonstrates the core DLL mechanism in isolation: shared.hpp declares an int with dllexport/dllimport, main.cpp defines answer=42 and LoadLibraryA's the plugin, plugin.cpp exports get_answer() which reads the shared variable.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: jll63

samples/windll/CMakeLists.txt

@@ -3,9 +3,8 @@
 # See accompanying file LICENSE_1_0.txt
 # or copy at http://www.boost.org/LICENSE_1_0.txt)
 
-# Illustrates the dllvar mechanism: the exe owns (exports) the registry state;
-# the DLL imports it, contributing overriders that are consolidated by
-# initialize() before first use.
+# Illustrates the exe-exports-data / DLL-imports-data pattern on Windows:
+# the exe defines and exports a variable; the DLL imports and reads it.
 #
 # On non-Windows both compilation units are linked into a single executable.
 
@@ -14,11 +13,10 @@ if (WIN32 OR CYGWIN)
     add_executable(windll_main main.cpp)
     target_compile_definitions(windll_main PRIVATE WINDLL_OWNER)
     set_target_properties(windll_main PROPERTIES ENABLE_EXPORTS ON)
-    target_link_libraries(windll_main PRIVATE Boost::openmethod)
 
-    # DLL imports the registry state from the exe.
+    # DLL imports the variable from the exe.
     add_library(windll_plugin SHARED plugin.cpp)
-    target_link_libraries(windll_plugin PRIVATE Boost::openmethod windll_main)
+    target_link_libraries(windll_plugin PRIVATE windll_main)
     set_target_properties(windll_plugin PROPERTIES ENABLE_EXPORTS ON)
 
     # windll_main loads windll_plugin at runtime; build both before testing.
@@ -32,7 +30,6 @@ else()
     # Non-Windows: single executable, no DLL decoration needed.
     add_executable(windll_main main.cpp plugin.cpp)
     target_compile_definitions(windll_main PRIVATE WINDLL_OWNER)
-    target_link_libraries(windll_main PRIVATE Boost::openmethod)
 
     add_test(NAME windll COMMAND windll_main)
 endif()

samples/windll/main.cpp

@@ -3,31 +3,25 @@
 // See accompanying file LICENSE_1_0.txt
 // or copy at http://www.boost.org/LICENSE_1_0.txt)
 
-// This module owns the registry state (WINDLL_OWNER -> dllexport).
 #define WINDLL_OWNER
 #include "shared.hpp"
-#include <boost/openmethod/initialize.hpp>
 #include <cassert>
-#include <string>
 #ifdef _WIN32
 #include <windows.h>
 #endif
 
-using namespace boost::openmethod;
-
-BOOST_OPENMETHOD_CLASSES(Animal, Dog);
-BOOST_OPENMETHOD_OVERRIDE(speak, (virtual_ptr<Animal>), const char*) { return "?"; }
+int answer = 42;
 
 int main() {
 #ifdef _WIN32
-    // Load plugin before initialize() so its static constructors register
-    // the Dog overrider into the shared registry state.
-    LoadLibraryA("windll_plugin.dll");
+    auto plugin = LoadLibraryA("windll_plugin.dll");
+    assert(plugin);
+    auto get_answer = (int (*)())GetProcAddress(plugin, "get_answer");
+    assert(get_answer);
+    assert(get_answer() == 42);
+    FreeLibrary(plugin);
+#else
+    extern int get_answer();
+    assert(get_answer() == 42);
 #endif
-    initialize();
-
-    Dog d;
-    assert(speak(virtual_ptr<Dog>::final(d)) == std::string("woof"));
-    Animal a;
-    assert(speak(virtual_ptr<Animal>::final(a)) == std::string("?"));
 }

samples/windll/plugin.cpp

@@ -3,10 +3,14 @@
 // See accompanying file LICENSE_1_0.txt
 // or copy at http://www.boost.org/LICENSE_1_0.txt)
 
-// This module imports the registry state from the exe (no WINDLL_OWNER).
 #include "shared.hpp"
 
-using namespace boost::openmethod;
+#ifdef _WIN32
+#define EXPORT __declspec(dllexport)
+#else
+#define EXPORT
+#endif
 
-BOOST_OPENMETHOD_CLASSES(Animal, Dog);
-BOOST_OPENMETHOD_OVERRIDE(speak, (virtual_ptr<Dog>), const char*) { return "woof"; }
+extern "C" EXPORT int get_answer() {
+    return answer;
+}

samples/windll/shared.hpp

@@ -5,20 +5,16 @@
 
 #pragma once
 
-// Define WINDLL_OWNER in the module that owns (exports) the registry state.
-// All other modules that link against it automatically import it.
+// The module that owns (exports) the variable defines WINDLL_OWNER before
+// including this header. All other modules import it.
 #ifdef _WIN32
 # ifdef WINDLL_OWNER
-#   define BOOST_OPENMETHOD_EXPORT_DEFAULT_REGISTRY
+#   define WINDLL_API __declspec(dllexport)
 # else
-#   define BOOST_OPENMETHOD_IMPORT_DEFAULT_REGISTRY
+#   define WINDLL_API __declspec(dllimport)
 # endif
+#else
+# define WINDLL_API
 #endif
 
-#include <boost/openmethod.hpp>
-
-struct Animal { virtual ~Animal() = default; };
-struct Dog    : Animal {};
-
-BOOST_OPENMETHOD_CLASSES(Animal, Dog);
-BOOST_OPENMETHOD(speak, (boost::openmethod::virtual_ptr<Animal>), const char*);
+WINDLL_API extern int answer;