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POHow do I write the move assignment function for this derived class?
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copied!<p><a href="https://connect.microsoft.com/VisualStudio/feedback/details/800114/-default-not-working-for-move-constructor-in-visual-c-2013-rc">Due to this bug in Visual Studio 2013</a>, I need to provide my own move constructor and move assignment for a derived class. However, I don't know how to call the appropriate move functions for the base class.</p> <p>Here's the code:</p> <pre><code>#include <utility> // Base class; movable, non-copyable class shader { public: virtual ~shader() { if (id_ != INVALID_SHADER_ID) { // Clean up } } // Move assignment shader& operator=(shader&& other) { // Brett Hale's comment below pointed out a resource leak here. // Original: // id_ = other.id_; // other.id_ = INVALID_SHADER_ID; // Fixed: std::swap( id_, other.id_ ); return *this; } // Move constructor shader(shader&& other) { *this = std::move(other); } protected: // Construct an invalid shader. shader() : id_{INVALID_SHADER_ID} {} // Construct a valid shader shader( const char* path ) { id_ = 1; } private: // shader is non-copyable shader(const shader&) = delete; shader& operator=(const shader&) = delete; static const int INVALID_SHADER_ID = 0; int id_; // ...other member variables. }; // Derived class class vertex_shader final : public shader { public: // Construct an invalid vertex shader. vertex_shader() : shader{} {} vertex_shader( const char* path ) : shader{path} {} // The following line works in g++, but not Visual Studio 2013 (see link at top)... //vertex_shader& operator=(vertex_shader&&) = default; // ... so I have to write my own. vertex_shader& operator=(vertex_shader&&) { // What goes here? return *this; } vertex_shader(vertex_shader&& other ) { *this = std::move(other); } private: // vertex_shader is non-copyable vertex_shader(const vertex_shader&) = delete; vertex_shader& operator=(const vertex_shader&) = delete; }; int main(int argc, char* argv[]) { vertex_shader v; // later on v = vertex_shader{ "vertex_shader.glsl" }; return 0; } </code></pre> <p>What should the move assignment function in the derived class look like?</p>

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