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--- cplusplus:goingnative2013 [2013/09/18 10:14]
dblume
+++ cplusplus:goingnative2013 [2022/10/06 00:39] (current)
dblume [Advanced Optimization] whitespace only
@@ Line 67: / 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.