Re: constructing and initializing a scoped_array

From:
boaz_sade@yahoo.com
Newsgroups:
comp.lang.c++
Date:
1 Jun 2006 12:44:58 -0700
Message-ID:
<1149191098.134134.187390@u72g2000cwu.googlegroups.com>
Victor Bazarov wrote:

Dennis Jones wrote:

I have some old code that I am refactoring to use smart pointers and
have run into a small problem. My original code looks something like
this:

class WorkerThread
{
   std::map<int, Handler> &HandlerMap;
public:
   WorkerThread( std::map<int, Handler> &AHandlerMap )
       : HandlerMap( AHandlerMap ) {}
};

WorkerThread *WorkerThreads[MAXTHREADS];

for ( int i=0; i<MAXTHREADS; i++ )
{
   WorkerThreads[i] = new WorkerThread( TheHandlerMap );
}

And I think I'd like to change it to use a scoped_array:

boost::scoped_array< WorkerThread > WorkerThreads;

WorkerThreads( new WorkerThread[/*...*/] )

Unfoortunately, the WorkerThread class does not have a default
constructor, and as such, the compiler does not allow me to cosntruct
a scoped_array. So maybe a scoped_array isn't the way to go, but it
seemed like most obvious choice. What would be an appropriate
solution?


I have no idea what 'scoped_array' is (it's not part of the Standard
Library, AFAICT), but can you tell me what's inaproppriate about, say,
'std::vector'?

V
--
Please remove capital 'A's when replying by e-mail
I do not respond to top-posted replies, please don't ask

I think that the main problem with vector will be the fact that he is
allocating those objects on the heap - they are pointers and vector is
not so great for those cases, in any case he will run in to the same
problem with vector since vector need the stored object to have default
ctor.
But why not to use boost::ptr_map? it was designed for holding pointers
which is what you code is doing. Then you don't need shared_ptr. Read
the docs for this.

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