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December 31, 2006
Re: class allocators should be more encapsulated
Luís Marques wrote:
> Frits van Bommel wrote:
>> Yes they do take parameters, and the reason is indeed to customize how 
>> memory is allocated. But unless they throw an exception, they do have 
>> to actually _allocate_ some memory. If they don't throw, the return 
>> value must be a void* to a newly-allocated piece of memory.
>> So what I gather you're trying to do (potentially return a pointer to 
>> an already-existing object) isn't acceptable behavior for a custom 
>> allocator.
> 
> You are right. If I return an existing object it will be initialized to 
> default values. I guess that means the solution to a singleton pattern 
> proposed by Burton Radons does not work 
> (http://www.digitalmars.com/pnews/read.php?server=news.digitalmars.com&group=D&artnum=14520) 
> 
> 
> Still, it's a pity that "new ClassType()" cannot be used to 
> transparently return an existing object (conditionally or not).
> 
> -- 
> Luís Marques

Why should "new ClassType()" be able to return the same instance? What's 
wrong with ClassType.getInstance() ? Or in your case 
ClassType.getInstance("my string") ?

-- 
Bruno Medeiros - MSc in CS/E student
http://www.prowiki.org/wiki4d/wiki.cgi?BrunoMedeiros#D
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