Detector for unused variables

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> Plenty of the community agrees with him too, much as there may 
> be some vocal
> folks who don't. Regardless, because he's the gatekeeper of the 
> reference
> compiler, he has to be convinced if you want a feature added to 
> either the
> language or the compiler. He's generally quite reasonable, but 
> he also
> has a high bar for feature changes.
>
> - Jonathan M Davis

That's right. But the majority of programming languages has this 
feature, but D does not. This feature is undeniable effective, so 
IMO there is no reason which stands against a warning for unused 
variables. Or can you tell me some personal reasons, without 
quoting Walter?