boost::thread

[l2u]

Hello

I have a class someclass with somefunction;

Now I want to create a boost thread with somefunction:

someclass sc;
boost::thread thr(&sc.somefunction);
thr.join();

What am I doing wrong?
Should I use bind instead?

[Mario F.]

To start with you aren't doing what you think. You aren't passing a reference to the somefunction() member function.

You can't get the address of a member function for reasons having to do with the fact member functions add an extra parameter (the *This parameter) . You can however define a static function and create your member function to call it. It is then possible to get the address of a static function with the following syntax:

&Class::static_function

[ChaosEngine]

what Mario F. said is true, however you can achieve the effect you're looking for with boost.bind

someclass sc;

// assuming somefunction takes no params
boost::thread thr(boost::bind(&someclass::somefunction, sc);
thr.join();

I love bind. It's just so awesome, I don't think I could program in C++ without it anymore.

[Mario F.]

I'm actually wanting to study boost::bind and the acompanying function object libraries. Only read good things about them. You just shown me another reason

[ChaosEngine]

it is cool, but you have to be careful. when you find yourself writing code like this

std::for_each (m_elementList.begin(),
               m_elementList.end(), 
               bind(TiXmlElement::SetAttribute,
                    pNewElement,
                    bind(XMLBaseElement::GetName, _1),
                    bind(XMLBaseElement::GetStringValue, _1)));
// equiv to 
// for each iter in m_elementList
//      pNewElement->SetAttribute((*iter)->GetName(), (*iter)->GetStringValue());

it's probably time to just use a for loop