Hello shunsuke, Monday, May 14, 2007, 5:05:46 PM, you wrote:
Andrey Semashev wrote:
Currently is_const_iterator will result to true only if the iterator reference type is const value or const reference. I'm not sure how it should behave for iterators with a non-const value reference types and vector< bool >::iterator specifically. I'm leaving this to users to define by specializing is_const_iterator on their iterator types. Maybe there should exist specialization on vector< bool >::const_iterator right out of the box?
I'm not sure, but this is an interesting question: Is it feasible to detect the writability of iterator using some language magic? If not, is_const_iterator can be a practical workarond.
The more I think of it the more I like the following solution: - Make it fail to compile if dereferencing the iterator yelds a non-reference type - Provide specializations for vector< bool > iterators - Add a note to the library docs about that But I'd like to see what Dave thinks about it, as the library author.
Well, I looked at the 'MyList' example. 'transform_iterator' could not be used?
Theoretically it could. But it seems to me a too heavy solution. The iterator would contain a functor, which: a) I don't need b) either may be of unknown type (in case of bind or lambda expressions) or is an additional class which I find very inconvenient. To my mind, transform_iterator is handy when you want to provide a view of the container to some algorithm from your (user's) code. It is an overkill to use it as a part of a container implementation (library code). -- Best regards, Andrey mailto:andysem@mail.ru