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Re: Draft of Binary module

From: Michael Kay <mike@saxonica.com>
Date: Thu, 14 Mar 2013 09:07:48 +0000
Message-ID: <51419364.9060903@saxonica.com>
To: Christian Grün <christian.gruen@gmail.com>
CC: Adam Retter <adam@exist-db.org>, Florent Georges <fgeorges@fgeorges.org>, EXPath <public-expath@w3.org>
 >On the other hand, most XPath functions work with integers, which is 
why you will usually end up with a 32bit representation of your value 
anyway.

Minor correction: there's nothing intrinsically 32-bit about an XPath 
integer.

 >From the implementor’s perspective, I believe it should usually be 
possible to find memory-saving optimizations for both variants; but it 
would be interesting to hear more about other implementations.

Saxon implements xs:integer (and all its subtypes) using an object that 
wraps a java long if it fits in a long, or a java BigInteger if not. 
Sure, there are representations that would be smaller and faster, but I 
don't think that making savings on the way we handle integers has ever 
been on anyone's critical path.

Of course, for the integer sequence that results from binary-to-octets, 
we would not materialize the integers eagerly.

In Saxon-CE we use java BigDecimal throughout. Makes everything much 
simpler.

Michael Kay
Saxonica
Received on Thursday, 14 March 2013 09:08:18 GMT

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