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From: Brad Moore <brad.moore@shaw.ca>
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Subject: Re: Safety of unprotected concurrent operations on constant objects
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Date: 2014-05-05T16:46:26-06:00
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On 04/05/2014 12:55 PM, Jeffrey Carter wrote:
> If you're interested in a solution that is not GNAT-specific, the
> skip-list implementation in the PragmAda Reusable Components has a
> Search operation that is task safe. It's easy enough to use a skip list
> as an ordered map. You'd have to use a[n] [Un]Bounded_String for the
> key, but that shouldn't be too much of a problem.
>
> The PragmARCs are available from
>
> http://pragmada.x10hosting.com/pragmarc.htm
>

You might want to also have a look at the parallel red-black trees in 
the paraffinalia folders at
http://sourceforge.net/projects/paraffin

Once the tree is populated, I think querying the tree should be task 
safe, so long as no new nodes are added or deleted. It also provides 
parallel iteration through the tree, if needed. The tree was not 
otherwise intended to be task safe, but given the description of the 
OP's needs ( a constant container object ), it might be suitable.