Re: [boost] [iterator] Is there general const_iterator adaptor?

TONGARI writes:

Hi folks,

I wonder if there's a general const_iterator adaptor that transforms any iterator to a const one:

template<class Iterator> struct const_iterator : iterator_adaptor < const_iterator<Iterator>, Iterator , typename iterator_value<Iterator>::type const > { const_iterator() {}

const_iterator(Iterator const& base) : const_iterator::iterator_adaptor_(base) {} };

Which is simple but handy for use in that we don't have to make 2 versions for both const & non-const iterators each time we make a container.

Does Boost offer this which I missed somewhere, or would you think it's a good idea to add?

If you look at the documentation of iterator_facade you will see that it already shows how to just write one version of the iterator and get a const version for free: pass a `const T` as the second argument of iterator_face and it should work. HTH, Philipp