Hi

You need a const_iterator whenever you want to iterate through a const
container
e.g.

void myfunction(const std::list<mytype>& mylist_readonly)
{
        // Causes an error at compile time=20
        std::list<mylist>::iterator bad_it =3D mylist_readonly.begin();

        // This time is fine=09
        std::list<mylist>::const_iterator good_it=3D mylist_readonly.begin();=20
}


Gilles


-----Message d'origine-----
De: Phil Beck [mailto:phil@EF-X.COM]
Date: jeudi 17 mai 2001 10:25
=C0: ATL@DISCUSS.MICROSOFT.COM
Objet: OT: STL


Just a quickie.

When iterating through a container such as :-

std::list<mytype>

why do I sometimes need a const_iterator instead of just an iterator ?
Using an iterator sometimes give me the compile error :-

binary '=3D' no operator defined which takes a right hand operand of =
type
std::list<class mytype,class std::allocator<class mytype> >::iterator

Phil.

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