Re: [xml-dev] XML design of ((a and b) or c)

[Rick Marshall <rjm@zenucom.com>]

Technically "and" and "or" are commutative so it doesn't matter in a 
maths sense either.

However compiler and script optimisation means that order of evaluation 
does matter. So in computing circles the these operators are no longer 
commutative.

blame stephen bourne (i think he started this).

The famous sh script: programA && programB etc where programB is only 
run if programA returns true.

;)

Rick

Alexander Johannesen wrote:
> Hi,
>
> On 12/13/06, David Carlisle <davidc@nag.co.uk> wrote:
>> > But I guest is a doomed approach because I dont think XML is
>> > order-stable, so will make horrible things with a operation where
>> > order matter :(
>>
>> If XML didn't preserve order by default you wouldn't want to use it for
>> marking up documents, books, ... they don't usually react too well to
>> having paragraphs reshuffled.
>
> Yup. You've got your elements in order in XML; it's the attributes
> that have no order guarantee, although I haven't stumbled across any
> XML parser that don't do LtoR parsing of them.
>
>
> Alex