Re: [Boost-users] [unordered] Iterator default constructor usage

Subject: Re: [Boost-users] [unordered] Iterator default constructor usage
From: Marshall Clow (mclow.lists_at_[hidden])
Date: 2011-11-25 16:47:04

On Nov 25, 2011, at 1:07 PM, andpar83_at_[hidden] wrote:

> Hi all.
> 
> Is it a correct usage of default constructor of iterators? Are any
> gurantees that it will always equals to the iterator returned by
> end()? :
> 
>       typedef boost::unordered_map<std::string, int> map;
>       map x;
>       x["one"] = 1;
> 
>       assert(x.find("missing") == x.end());
>       assert(x.find("missing") == map::iterator());
>       assert(map::iterator() == x.end());

How could they be?

Consider the following code:

        std::vector<int> v1, v2;
        std::vector::iterator i1;
        
Should
        i1 == v1.end ()
or	i1 == v2.end ()

be true? (they cannot both be true)

-- Marshall

Marshall Clow     Idio Software   <mailto:mclow.lists_at_[hidden]>

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