[boost] Re: [filesystem + iterator] directory iterator problem

From: Vladimir Prus (ghost_at_[hidden])
Date: 2004-04-27 01:09:40

David Abrahams wrote:

>>> I don't think you need that other requirement.  Remember, an invalid
>>> iterator can't be incremented.  So if r is dereferenceable, it's
>>> valid. You're still allowed to increment s (a copy of r) after r is
>>> incremented, so it can't have been invalidated by incrementing r.
>>> 
>>> If you're interested in *referent stability* of copies of r,
>>
>> What's 'referent stability'?
> 
> the stability of "what's referred to" by the iterator.

E.g. stability of *reference*? Or stability of the referred value?

>>>> BTW, do new iterator requirement state that iterator type X is
>>>> interoperable with itself?
>>> 
>>> Not explicitly, but that is certainly a logical implication of the
>>> requirements on single pass iterators.
>>
>> How? I can't decude that from any of singla pass iterator requirements.
> 
> Incrementable iterator is a refinement of Assignable and Copy
> Constructible, and == is an equivalence relation, etc.

equivalence relation, in mathematical sense is a relation which is
reflexive, transitive, and symmentric. Hmm.. I guess I only need to
understand this requirement for Assignable:

   t = u     post: t is equivalent to u

...

- Volodya