[Boost-users] Re: boost::iterator_facade problem with postfix increment proxy

From: Jens Theisen (jens.theisen_at_[hidden])
Date: 2005-03-24 04:43:00

David Abrahams wrote:
>>List< char >  l = makeList(some_std_string) + makeList(some_char_array);
> 
> We call that "any_iterator" (see
> http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?LibrariesUnderConstruction)

I think I focusing more on compounds like the above concatenation, but 
also filters and maps. I want to have the list expressiveness of Lisp, 
Haskell or Python to define what collections I want to have rather than 
using the stl algorithms to tell how collections are being contructed.

> Well, a generalized single-pass iterator can't be writable unless it
> has a proxy reference, IIRC.  Otherwise, how does
>        *x = a; 
> work?

According to the new iterator concepts it should be perfectly fine to 
have an lvalue access single-pass iterator. It is always up to the 
iterator's implementor what requirements he implements. Although I admit 
that this will be a rare combination and if my own iterators fall under 
these conditions, it's just because I'm lazy.

Best regards, Jens