Merge pull request #90 from john-lynch/master

Fixing move constructor/semantics of Final_act

include/gsl.h

@@ -50,16 +50,17 @@ template <class F>
 class Final_act
 {
 public:
-    explicit Final_act(F f) : f_(std::move(f)) {}
+    explicit Final_act(F f) : f_(std::move(f)), invoke_(true) {}
-    
+
-    Final_act(const Final_act&& other) : f_(other.f_) {}
+    Final_act(Final_act&& other) : f_(std::move(other.f_)), invoke_(true) { other.invoke_ = false; }
     Final_act(const Final_act&) = delete;
     Final_act& operator=(const Final_act&) = delete;
-    
+
-    ~Final_act() { f_(); }
+    ~Final_act() { if (invoke_) f_(); }
 
 private:
     F f_;
+    bool invoke_;
 };
 
 // finally() - convenience function to generate a Final_act

tests/utils_tests.cpp

@@ -37,6 +37,20 @@ SUITE(utils_tests)
         CHECK(i == 1);
     }
 
+    TEST(finally_lambda_move)
+    {
+        int i = 0;
+        {
+            auto _1 = finally([&]() {f(i);});
+            {
+                auto _2 = std::move(_1);
+                CHECK(i == 0);   
+            }
+            CHECK(i == 1);   
+        }
+        CHECK(i == 1);
+    }
+
     TEST(finally_function_with_bind)
     {
         int i = 0;