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From: "David Allsopp" <dra-news@metastack.com>
To: <luc.maranget@inria.fr>
Cc: "'bluestorm'" <bluestorm.dylc@gmail.com>,
	<caml-list@yquem.inria.fr>,
	"'W Dan Meyer'" <wojciech.meyer@googlemail.com>
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Subject: RE: [Caml-list] Converting variants with only constant constructors to integers
Date: Tue, 8 Jun 2010 10:45:20 +0100
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Luc Maranget wrote:
> Of course, if you have the following:
> >
> > type t = A | B | C
> > let int_of_t = function
> >   A -> 0
> > | B -> 1
> > | C -> 2
> >
> > Then in fact I believe that the compiler already converts that to a
> > hashtable lookup instead of a sequence of jumps..
> 
> The compiler does not convert the above code to 'hashtable lookup'.

Is there a point where the compiler does do a table lookup for matches
rather than jumps or have I clearly just dreamt that? :o)


David