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POPointer to member, within class
 

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    <p>I am trying create a typedef for a template that needs a pointer to member, from within a class. The best way to describe it is to show the minimal sample code:</p> <pre><code>template&lt;typename T, int T::*MV&gt; struct Bar { const int &amp;value(const T &amp;t) const { return (t.*MV); } }; struct Foo { int baz; typedef Bar&lt;Foo, &amp;Foo::baz&gt; GetBaz; // Compiler error }; typedef Bar&lt;Foo, &amp;Foo::baz&gt; GetFooBaz; // Compiles just fine int main(int argc, char* argv[]) { Foo f = { 42 }; Foo::GetBaz b; // Fails to compile GetFooBaz b2; // Fine int val = b.value(f); // Fails to compile because of above int val2 = b2.value(f); // Fine } </code></pre> <p>I am not necessarily dead-set on getting access to a member pointer in this way, I would be fine just knowing the offset to the variable and having the Bar::value function perform trickery.</p> <p>As a last resort, I suppose I could use a traits class since the would move the definition outside of the class, but I would prefer to be able to declare the typedef near the variable being used.</p> <p>And, to answer the "why would you want to do that" question, this is all for an IoC container that closely represents the way MEF (C# works).</p> <p>The specific compiler I am using is VC12, but it would be nice if VC11 supported it as well.</p> <p>Thanks</p> <p>EDIT:</p> <p>Here are the error messages</p> <p>1>------ Build started: Project: MemVarBug, Configuration: Debug Win32 ------ 1> MemVarBug.cpp 1>memvarbug.cpp(20): error C2327: 'Foo::baz' : is not a type name, static, or enumerator 1>memvarbug.cpp(20): error C2065: 'baz' : undeclared identifier 1>memvarbug.cpp(20): error C2975: 'MV' : invalid template argument for 'Bar', expected compile-time constant expression 1> memvarbug.cpp(7) : see declaration of 'MV' ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========</p>
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    1. COPlease post the compiler error messages.
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    2. COCompiles just fine with gcc-4.6.1.
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    3. CO@n.m. The question is tagged vc12
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