> Does XSLT 2.0 implement lazy evaluation?

That's entirely at the discretion of the processor.
>
> I ask this because the following example returned 4 in XSLT
> 1.0 but generates an error in XSLT 2.0 processors.

3 div 0 used double arithmetic in 1.0 and generated +INF. In 2.0 it uses
decimal arithmetic and generates a divide-by-zero error. This is one of
those documented incompatibilities which you can avoid if you leave
version="1.0" to run in backwards compatibility mode.

It's true that a processor might not evaluate $y and therefore might not
raise the error. That's equally true of 1.0 and 2.0 (the difference is that
in 1.0 there's no error here). However, with an expression that can be
evaluated at compile time, lazy evaluation doesn't seem a particularly
sensible strategy.

Michael Kay
http://www.saxonica.com/

>
> <xsl:stylesheet
>
> xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>         version="2.0">
>
> <xsl:template match="/">
>  <xsl:call-template name="f">
>   <xsl:with-param name="x" select="2" />
>   <xsl:with-param name="y" select="3 div 0" />
> </xsl:call-template> </xsl:template>
>
> <xsl:template name="f">
>  <xsl:param name="x" />
>  <xsl:param name="y" />
>  <xsl:value-of select="$x + $x" />
> </xsl:template>
>
> </xsl:stylesheet>
>
>
>
>
>
> ______________________________________________
> LLama Gratis a cualquier PC del Mundo.
> Llamadas a fijos y msviles desde 1 cintimo por minuto.
> http://es.voice.yahoo.com