Re: [sigc] templates and my problem

[Kjell Ahlstedt <kjell ahlstedt bredband net>]

2012-08-01 16:45, Mohsen Pahlevanzadeh skrev:
> Dear all,
>
> I have 2 question: a. about the libsigc b. about (this) word and typeof
> or decltype
> I have NetworkSocket class and coded in main() func such as the
> following:
> ///////////////////////////////////
> NetworkSocket *oo = new NetworkSocket();
> oo->ready.connect(sigc::ptr_fun(&NetworkSocket::createThread));
> oo->run();
> ///////////////////////////////////////
> Above code get the following error:
> /////////////////
> error: no matching function for call to ‘ptr_fun(bool (NetworkSocket::*)())’
> ////////////////
>
> When i comment the above code , and put the following code in constructor :
> //////////////////////////////////////
> typeof(this) sig = new NetworkSocket();
> sig->ready.connect(sigc::ptr_fun(createThread));
> this->run();
> ////////////////////////////////////////
> I get the following error:
> ////////////////////////////////
> error: no matching function for call to ‘ptr_fun(<unresolved overloaded function type>)’
> ////////////////////////////////
> So , i think g++ can't understand type of this reserverd word.And i don't understand no match call function.
>
> Yours,
> Mohsen
Is NetworkSocket::createThread() a static member function? If it's not 
static, you must use sigc::mem_fun() instead of sigc::ptr_fun().

NetworkSocket *oo = new NetworkSocket();
oo->ready.connect(sigc::mem_fun(*oo, &NetworkSocket::createThread));
oo->run();

or

typeof(this) sig = new NetworkSocket();
sig->ready.connect(sigc::mem_fun(*this, &NetworkSocket::createThread)); 
// or mem_fun(*sig...?
this->run();

but here you have 2 NetworkSocket objects, *this and *sig. Is that what 
you want? Should it be

ready.connect(sigc::mem_fun(*this, &NetworkSocket::createThread));
this->run();

What makes you suspect that g++ does not understand typeof(this)? You 
don't mention any error message that contains 'typeof'.