add module file for scope and modular example

Author: JeffGarland

examples/scope-module.cpp

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+// This example uses c++20 modules with beman.scope
+//
+// The following are by hand instructions for compiling with g++-15
+// first line generates gcm.cache file for standard headers - one time only
+// g++-15 -std=c++26 -O2 -fmodules -fsearch-include-path -fmodule-only -c bits/std.cc
+// g++-15 -std=c++26 -O2 -fmodules -fmodule-only -c ${scope_top}/include/beman/scope/beman.scope.cppm
+// g++-15 -std=c++26 -fmodules scope-module.cpp
+//
+// prints:
+// --> scope start
+// construct noisy
+// --> scope end
+// destroy noisy
+// scope exit: true success: true fail: false 
+
+import std;
+import beman.scope;
+
+struct noisy_resource
+{
+  noisy_resource()  { std::print("construct noisy\n"); }
+  ~noisy_resource() { std::print("destroy noisy\n");   }
+};
+
+int main()
+{
+
+  bool exit_ran, success_ran, fail_ran = false;
+  {
+    std::print( "--> scope start\n" );
+    beman::scope::scope_exit    _([&exit_ran]   { exit_ran = true;   });
+    beman::scope::scope_success _([&success_ran]{ success_ran = true;});
+    beman::scope::scope_fail    _([&fail_ran]   { fail_ran = true;   });
+    auto resource_ptr = beman::scope::unique_resource
+    (
+       new noisy_resource(),
+       // Cleanup function
+       [](noisy_resource* ptr) { delete ptr; }
+    );
+    std::print( "--> scope end\n");
+  } // Normal scope exit
+
+  std::print("scope exit: {} success: {} fail: {} \n",
+	     exit_ran, success_ran, fail_ran);
+}

include/beman/scope/beman.scope.cppm

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+// create the beman.scope.gcm in gcm.cache directory
+// g++-15 -std=c++26 -O2 -fmodules -fmodule-only -c ${scopetop}/include/beman/scope/beman.scope.cppm
+module;
+
+#include "scope.hpp"
+
+export module beman.scope;
+
+export namespace beman::scope {
+    using ::beman::scope::scope_exit;
+    using ::beman::scope::scope_fail;
+    using ::beman::scope::scope_success;
+    using ::beman::scope::unique_resource;
+}