[Project] List & ConstIterator

[Igmar Palsenberg]

Try a C++ newsgroup.


Igmar

 

[hokus]

I have the following class:

<CODE>

class List
{
public:

class Node
{
public:
Node* m_next;
};

class Iterator
{
public:
Node *m_position;
};

class ConstIterator
{
public:
ConstIterator( Node* pos );
Node *m_position;
};

// utility functions
ConstIterator begin() const;
Iterator begin();

// data members
Node* m_head;

};

</CODE>

The problematic implementation of const begin is:

<CODE>

List::ConstIterator
List::begin() const
{
return List::ConstIterator(m_head);
}

</CODE>

This is wrong because it is impossible to convert const List::m_head to just
pointer. My question is how to project class List to use Iterator and
ConstIterator functionality? I know I can use const_cast to remove constant
property from const List::m_head pointer but I think this isn't a good idea.

Thanks

 

[Martin Ambuhl]

I have the following class:

<CODE>

class List
{
public:

[etc.]
If you have a question about C++, ask in < In
<questions about such a byzantine language are frowned
on and not answered. If someone should post an answer, treat it with
all the respect you would give an answer from an APL, LISP, Fortran, or
Forth programmer about C++; that is to say, none.

 

[Emmanuel Delahaye]

hokus wrote on 29/09/05 :

I have the following class:

Try a Pascal news group... (but avoid a C++ news group, it would be too
easy...)

--
Emmanuel
The C-FAQ: http://www.eskimo.com/~scs/C-faq/faq.html
The C-library: http://www.dinkumware.com/refxc.html

I once asked an expert COBOL programmer, how to
declare local variables in COBOL, the reply was:
"what is a local variable?"