Re: [Boost-users] [thread] About the virtual in virtual operator()

Subject: Re: [Boost-users] [thread] About the virtual in virtual operator()
From: Nigel Rantor (wiggly_at_[hidden])
Date: 2009-10-31 17:14:39

Richard Vock wrote:
>> The smallest change to your code I think would be this 
> though.
>> ---
>> thread t( boost::bind( &Kernel::operator(), m_kernel[i] ) 
> );
>> t.join();
> 
> I've always had problems understanding boost::bind, but this
> helps a lot.
> 
> And it works too...
> 
> Thank you!

I realise this solves your problem but didn't really answer your 
question though.

The reason it doesn't work with an abstract class is because the thread 
class attempts to copy the functor you're passing in. Since Kernel is 
abstract you can't do this.

If you make Kernel a concrete class you get a different problem.

The statement:

thread t( *(m_kernel[i]) )

slices the object down to a plain old Kernel, irrespective of what the 
pointer originally referenced.

You can only call virtual functions through pointers or references so 
you lose dynamic binding once this happens.

   n