[Boost-users] [enable_shared_from_this] My derivation of enable_shared_from_this wants to be templated

Subject: [Boost-users] [enable_shared_from_this] My derivation of enable_shared_from_this wants to be templated
From: Rob Currey (avalonforest_at_[hidden])
Date: 2009-03-04 14:51:36

Here's some code based upon the example at :
http://www.boost.org/doc/libs/1_38_0/libs/smart_ptr/enable_shared_from_this.html

class X { public: X() { }; };

template<class X>
class Y: public enable_shared_from_this< Y<X> >
{
public:

    shared_ptr< Y<X> > f()
    {
        return shared_from_this();
    }
};

typedef Y<X> templatedY;

int main()
{
    shared_ptr<templatedY> p(new Y<X>);
    shared_ptr<templatedY> q = p->f();
    assert(p == q);
    assert(!(p < q || q < p)); // p and q must share ownership
}

compiles with:
$ gcc -o 
test -I/usr/local/include/boost-1_38 -lstdc++ -L/usr/local/lib -lboost_system-gcc41-mt 
test.cpp
test.cpp: In member function âboost::shared_ptr<Y<X> > Y<X>::f()â:
test.cpp:13: error: there are no arguments to âshared_from_thisâ that depend 
on a template parameter, so a declaration of âshared_from_thisâ must be 
available
test.cpp:13: error: (if you use â-fpermissiveâ, G++ will accept your code, 
but allowing the use of an undeclared name is deprecated)

Any resolution (other than the -fpermissive hack)

TIA (my skilz with shared_ptr<> are somewhat lacking ...)