[xsl] Why is RelationalExpr left associative?

Subject: [xsl] Why is RelationalExpr left associative?
From: Oliver Becker <obecker@xxxxxxxxxxxxxxxxxxxxxxx>
Date: Sun, 29 Apr 2001 22:04:08 +0200 (MET DST)
Dear XPath experts,

can anyone give me the reason why the productions for EqualityExpr 
and RelationalExpr have been designed the way they are?
(See http://www.w3.org/TR/xpath#NT-RelationalExpr )
The note in the specification about 3 > 2 > 1 talks about a possible 
misinterpretation.
So the question is: why are these kinds of expressions allowed? Are 
there any useful situations in which one can benefit?

I think formulating the production for RelationalExpr to be
nonassociative like this

RelationalExpr ::= AdditiveExpr
                   | AdditiveExpr '<' AdditiveExpr
                   | AdditiveExpr '>' AdditiveExpr
                   | AdditiveExpr '<=' AdditiveExpr
                   | AdditiveExpr '>=' AdditiveExpr

would avoid such "nonsense" 3 > 2 > 1 expressions.

(Dito for EqualityExpr and the example 0 = 0 = 0).

Thanks for giving me any insights :-)
Cheers,
Oliver

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|  ob|do        Dipl.Inf. Oliver Becker                             |
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