Re: [xml] xpath mixed type equality expressions

[Daniel Veillard <veillard redhat com>]

On Mon, Jun 10, 2002 at 10:39:24PM +0200, Matthias Clasen wrote:
> I have a little problem with the xsl docbook stylesheets, which don't
> behave as expected with xsltproc. The problem can be condensed to the
> following:
>
>   <xsl:template name="test" match="*">
>     <xsl:variable name="value">1.0</xsl:variable>
>     <xsl:choose>
>       <xsl:when test="$value != 1.0">
>         <xsl:message>UNEQUAL</xsl:message>
>       </xsl:when>
>       <xsl:otherwise>
>         <xsl:message>EQUAL</xsl:message>
>       </xsl:otherwise>
>     </xsl:choose>
>   </xsl:template>
>
> This will print UNEQUAL when run trough xsltproc, although I believe
> that the XPath spec (section 3.4) specifies that it should print EQUAL, 
> since the test attribute is an EqualityExpression with a node-set and a
> number as operands. Such an expression shall evaluate to true if any
> node x in the node-set yields the given number when fed through
> number(string-value(x)). 
>
> libxml does't really implement this, but rather converts the number to a
> string (which converts 1.0 into "1") and then compares the
> string-value(x) with the resulting string (in xmlXPathEqualNodeSetFloat)
>
> I think this is a bug in libxml.

  Seems you're right and the way xmlXPathEqualNodeSetFloat() is implemented
doesn't respect the XPath semantic :-(
  bug_to_fix++

  thanks for the report !

Daniel


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