Pointer

inspiration · #1 06-14-2010, 07:19 PM

i!

Contributions about pointer to class methods are indeed
already in the forum. Still remain for me what this topic
concern, a few questions unanswered. Would be nice if someone
in answering the following questions might be helpful.

Will ultimately produce for me exactly two of ambiguity:
Problem 1:
----------

I would firstly like to pointer to class methods in a
LinkedList store.
ie:
the Konstruktorenaufruf could look like this:
LinkedList <void (ClassName::*)(void)> list ();

And now the crux:
so I give this call as a template parameter pointer
on methods of class 'Class Name' with the above structure to.

This approach I might now, for example, compared with the Ablau, the
would be required to create a LinkedList for 'ClassName' objects.
also:

a) LinkedList <ClassName *> list ();

A call to like this would be also valid
(I would only adjust the LinkedList internal):

b) LinkedList <ClassName> list ();

And here are my problems!

->
If treatment of the LinkedList, is as done as you b below)
also in the class methods possible?
Is to say:
I may in the call:
LinkedList (ClassName::*)(void)> <void, where I indeed a PointerType
specify, also specify a Klassenmethodentyp?
==> Looks like the syntax for then?

Problem 2:
----------

In various posts in the forum already mentioned that in a
Calling a class method always binding to a specific object is required.
ie:
either as outside of the object like this: (object-> * object-> methodPtr) ();

or within the object like this: (this-> this-*> methodPtr) ();

In this approach, but is always assumed that the methods Pointer
as an attribute of 'object' is present.

What is it but now, if I belong to the object a pointer a
specific class method is present!
How do I call for then the class method?
How do I bind because now the method of the object?

Would be nice if someone could help on the jumps!

inspiration · #2 06-14-2010, 07:20 PM

OK!
Item number two has done it!
Only as far as problem number one, am
I, unfortunately, still no further!

Can someone help me also to this evil
? Eliminate

techme · #3 06-14-2010, 07:21 PM

So std:: list

Code:

# Include <list> 
using namespace std; 

class foo 
( 
public: 
    void f1 () () 
    void f2 () () 
); 

int main () 
( 
    typedef void (foo:: * mem_func_ptr) () / / not necessary but nice 
    list <mem_func_ptr> bla; 
    bla.push_back (& foo:: f1); 
    bla.push_back (& foo:: f2); 

    foo f; 
    for(list <mem_func_ptr>:: iterator i = bla.begin (); i! bla.end = (); + + i) 
        (F * (* i)) () 
)

creative · #4 06-14-2010, 07:22 PM

And if he wants to manage method-pointer coming from other classes as foo?

inspiration · #5 06-14-2010, 07:22 PM

First of all thank you for your answers!

But:
Maybe I am so, what problem number one is concerned,
expressed something unclear.

Syntax of the form:

typedef void (foo:: * mem_func_ptr) ();
list <mem_func_ptr> bla;

or:

list <void (foo::*)()> bla;

I know!

However, I still give as a template parameter
Methods-POINTER type to. I would be interested to know whether it
also be a method type is indicated (no Ptr).
In a normal class it works so well:

<ClassName *> list list () or list <ClassName> list ()

depending on what awaits the LinkedList.
I also see, in the appropriate literature, only the syntax
for method pointers,
So: Return value (class name ::*)( parameters)
but never, for a method type.

Is there such a construct, or perhaps not
is a fallacy in charge?

Please hold on!

meyup · #6 06-14-2010, 07:23 PM

I do not think that would be yes, would you put the function in the list. In C + + functions, but are not objects, they can not copy or delete or something. To that extent, I can not imagine that they could put that species and container.

techme · #7 06-14-2010, 07:25 PM

what you are looking binder

Code:

# Include <list> 
using namespace std; 

class foo 
( 
public: 
    void f1 () () 
    void f2 () () 

    typedef void (foo:: * mem_func_ptr) (); 
); 


class bar 
( 
public: 
    bar (foo * instance, foo:: mem_func_ptr func) 
        : Instanz_ (instance), 
             func_ (func) 
    ( 
    ) 

    void operator() () 
    ( 
        (Insatnz_-> * func_) (); 
    ) 
private: 
    foo * instanz_; 
    foo:: mem_func_ptr func_; 
); 

int main () 
( 

    list <bar> bla; 

    foo a; 
    bla.push_back (bar (& a, & foo:: f1)); 
    
    foo b; 
    bla.push_back (bar (& b, & foo:: f2)); 

    for(list <bar>:: iterator i = bla.begin (); i! bla.end = (); + + i) 
        (I) (); 
)

inspiration · #8 06-14-2010, 07:25 PM

Thank you!
So that I would be happy for the moment.

-> The idea to encapsulate methods and object pointers
and only then can I insert in the LinkedList
good use!

But would certainly also ne good idea, the class 'bar'
to write a template class and then one of these interface
'SuperBar' derived. Then I could even methods and object pointers
any class in 'bar' objects encapsulate and then, as' objects bar'
indeed 'SuperBar' objects are, as' SuperBar' objects in the LinkedList
list <SuperBar> bla insert.
==> Then I could add each item in the list of 'blah' as the command "execute () '
and assign each 'bar' object could be the referenced method
bind to the affected object and execute the method.
We'll see if it's funtzt!

Thank you for your help!

pankaj.sea · #9 06-14-2010, 07:26 PM

well, that funzt so far, only then it will only work with pointers SuperBar

list <SuperBar*> bla

inspiration · #10 06-14-2010, 07:27 PM

That's right!
For the LinkedList, which I used in my code sample
I have to specify a PtrTyp. Then I did not even care.

But what about if I write the LinkedList itself. As my
own list of template parameters interpreted certain Whether an object or
Ptrtyp, I can not control, is not it?

I think then the syntax should be correct!