Re: [boost] Iterator Adaptor Bug with Named Template Parameters

From: David Abrahams (dave_at_[hidden])
Date: 2002-10-07 06:42:33

"Dale" <dale.peakall_at_[hidden]> writes:

> Compiler: GCC 3.1
> Boost Version: 1.28.0
> 
> If you attempt to instantiate an iterator adaptor over a non-iterator type
> and just specify Base, Policies, Value and then use named parameters for
> Category and Distance the iterator adaptor class attempts to instantiate
> std::iterator_traits over the base class... which fails as the base class
> doesn't define any of the appropriate typedefs.
> 
> Specifying all the parameters (without using named template paramters)
> solves
> the problem.
> 
> However, the documentation suggests that if you specify Value, Reference and
> Pointer should default to Value& and Value* rather than using
> std::iterator_traits.
> 
> Perhaps they do, but it doesn't help if it still tries to instantiate
> iterator_traits.

Good point. Jeremy and I are going to be working on a complete
redesign of the library later this month, so we'll try not to put the
same bug in the new version ;-)

-- 
           David Abrahams * Boost Consulting
dave_at_[hidden] * http://www.boost-consulting.com