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POThis template code will not compile. Any ideas?
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  1. POThis template code will not compile. Any ideas?
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    copied!<p>I got this code from rhalbersma, but it does not compile in VC 2010. I don't know what I'm doing wrong.</p> <pre><code>template&lt;typename Derived&gt; struct enable_crtp { private: // typedefs typedef enable_crtp Base; public: // casting "down" the inheritance hierarchy Derived const* self() const { return static_cast&lt;Derived const*&gt;(this); } // write the non-const version in terms of the const version // Effective C++ 3rd ed., Item 3 (p. 24-25) Derived* self() { return const_cast&lt;Derived*&gt;(static_cast&lt;Base const*&gt;(this)-&gt;self()); } protected: // disable deletion of Derived* through Base* // enable deletion of Base* through Derived* ~enable_crtp() { // no-op } }; template&lt;typename FX&gt; class FooInterface : private enable_crtp&lt; FX &gt; { public: // interface void foo() { self()-&gt;do_foo(); } }; class FooImpl : public FooInterface&lt; FooImpl &gt; { private: // implementation friend class FooInterface&lt; FooImpl &gt; ; void do_foo() { std::cout &lt;&lt; "Foo\n"; } }; class AnotherFooImpl : public FooInterface&lt; AnotherFooImpl &gt; { private: // implementation friend class FooInterface&lt; AnotherFooImpl &gt;; void do_foo() { std::cout &lt;&lt; "AnotherFoo\n"; } }; template&lt;template&lt;typename&gt; class F, int X&gt; class BarInterface : private enable_crtp&lt; F&lt;X&gt; &gt; { // interface void bar() { self()-&gt;do_bar(); } }; template&lt; int X &gt; class BarImpl : public BarInterface&lt; BarImpl, X &gt; { private: // implementation friend class BarInterface&lt; ::BarImpl, X &gt;; void do_bar() { std::cout &lt;&lt; X &lt;&lt; "\n"; } }; int main() { FooImpl f1; AnotherFooImpl f2; BarImpl&lt; 1 &gt; b1; BarImpl&lt; 2 &gt; b2; f1.foo(); f2.foo(); b1.bar(); b2.bar(); return 0; } </code></pre>
 

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