Re: passing linked lists to functions

From: Unforgiven (jaapd3000_at_hotmail.com)
Date: 11/26/03 

Date: Wed, 26 Nov 2003 23:28:08 +0100

Victor Bazarov wrote:
>> I think that's working but I have another problem: I need to pass two
>> iterators also to this function which point to certain position in
>> the list, should these iterators be passed by reference. The above
>> syntax gives me syntax errors:
>> This is the call from main:
>> qhull(S1, index1, hull, hull.begin(), hull.end(), globalMin,
>> globalMax, rank,
>> numtasks);
>
> 'begin' and 'end' members return a _temporary_ iterator, which cannot
> be passed where a _non_const_ reference is expected. Change your
> 'qhull' function to accept " list<PARTICLE>::iterator const& " for
> both 'iter1' and 'iter2' arguments, and it will work.

That doesn't sound like a good idea to me, because you wouldn't be able to
call any non-const members, and I suppose (especially since his example call
uses begin() and end()) that he's going to want to use operator++, which is
non-const. Just pass the iterators by value, that should do the trick. 

-- 
Unforgiven
"You can't rightfully be a scientist if you mind people thinking
you're a fool."

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