Re: [boost] Re: Re: stride iterators and matricies

From: christopher diggins (cdiggins_at_[hidden])
Date: 2005-06-03 14:39:26

Christopher Diggins
http://www.cdiggins.com
----- Original Message ----- 
From: "Peter Dimov" <pdimov_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Friday, June 03, 2005 3:07 PM
Subject: Re: [boost] Re: Re: stride iterators and matricies

> Neal Becker wrote:
>
>> Here's my version:
>
> [...]
>
> One interesting problem with strided iterators is coming up with end 
> values. Suppose you have
>
> int x[ 4 ];
>
> and you want to iterate over x[1] and x[3] with stride 2. Your begin 
> iterator will be x+1, and your end iterator will be x+5 - an invalid 
> address.

I am very confused, isn't x+4 also an invalid address? What is the 
difference between x+4 and x+5 or any other address not within the range x 
to x+3 ?

- Christopher