Signal/Slot copy semantics.

16 Apr 2003

      I have a problem with the sematics of the the signal connect method.
Consider this simple program:

#include <iostream>
#include 

struct HelloWorld {
  void operator()() const {
    std::cout << "Hello, World!, the parallel world exist at "
              << (void *) this
              << std::endl;
  }
};

int main () {
  // Connect a HelloWorld slot
  HelloWorld hello;
  std::cout << "Main world at " << (void *) &hello << std::endl;

  boost::signal sig;
  sig.connect(hello);

  sig ();

  std::cout << "Thats all folks!\n";
  return 0;
}

It produces this output:
...
Main world at 0xbffff2e0
Hello, World!, the parallel world exist at 0x8056128
Thats all folks!
My problem is that the object signalled is not the same object that I subscribed to the signal.

Is this really what was inteded ?

Is the any rationale behind this behaviour ?

-- 

Jesper Bojesen			Medical Insight

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