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--- cplusplus:goingnative2013 [2013/09/09 16:19] – created dblume
+++ cplusplus:goingnative2013 [2022/10/06 00:39] – [Advanced Optimization] whitespace only dblume
@@ Line 24: / Line 24: @@
         cache[id] = sp = load_widget(id);
     return sp;
+}
+</file>
+In C++11, the following code is thread safe!  It's the Meyers Singleton.
+  * Thread safe fn statics
+  * Does destruction. No need for Alexandrescu's various destruction policies anymore!
+<file cpp thread_safe_meyers_singleton.cpp>
+widget& instance() {
+    static widget w;
+    return w;
 }
 </file>
@@ Line 55: / Line 67: @@
 CINDER_APP_BASIC( MyApp, RendererDx )
 </file>
+===== Advanced Optimization =====
+Use lambda in place of std::bind to save memory. A std::bind() on a pointer-to-member-function will allocate 24 bytes on the heap for the bind structure. If instead you use a lambda, then this fits into 4 bytes and avoids any allocation.
+Replace:
+    g(this, std::bind(&m_f, this)),
+With:
+    g(this, [this](){this->m_f();}),
+Note that subtle changes to object lifetimes is possible. This code:
+    std::bind(f, std::weak_ptr<Object>(n));
+is not the same as this code:
+    [n]{ f(std::weak_ptr<Object>(n)); }
+The above code will bind the shared_ptr<Node> into the lambda's capture, extending the lifetime.
+But it is the same as this:
+    [wp = std::weak_ptr<Object>(n)]{ f(wp); };
+In this case the lambda's capture only has the weak pointer.