Couple things: First, I'd dump this topic on the XSL list. Those folks love this kind of question, and they are good at helping with this kind of issue. Second, I'd look at making a key to hold the field-that-has-a-value-and-whose-next-sibling-has-a-value combos. Then, rather than read the whole document, the processor would read the key. If it works, that should reduce memory usage and increase performance.
Jay Bryant Bryant Communication Services robert frapples <[EMAIL PROTECTED]> 11/30/2004 03:09 PM Please respond to [EMAIL PROTECTED] To [EMAIL PROTECTED] cc Subject setting up tables differently based on existance of xml tags. (static variables, recursion, templates, and intrigue) Here's a (hopefully) interesting problem: (I've been editing this email every day. Every time I can't figure out how to do something, I come up with an alternate plan, assisted by a few people in #xml on irc.freenode.net. (Thank you Bebabo). I figured at this point I'd share my experiences. If you can think of better, faster, cleaner ways to do this, I'd love to hear from you.) source xml: <document> <field> <title>a</title> </field> <field> <title>b</title> <value/> <field> <title>c</title> <value/> </field> <field> <title>d</title> </field> <field> <title>e</title> <value/> </field> </document> What I want to happen is basically, for-each select="field", if <field> has a <value/> and the next <field> also has a value, have 4 cells in a row: field[n]/title, text , field[n+1]/title, 'text'. If <field> does not have a <value/> or if the next <field> does not have a <value/>, then have 2 cells: field[n]/title, and 'other text' with number-columns-spanned=3. My first thought was this: /-----------------------------------------------------------------------------------------\ . . . <xsl:variable name="col" select="''"/> <xsl:table-body> <xsl:for-each select="field"> <xsl:choose> <xsl:when test="value and not($col)"> <fo:table-row> <fo:table-cell><xsl:value-of select="title"/></fo:table-cell> <fo:table-cell>text</fo:table-cell> <xsl:variable name="col" select="'true'"/> </xsl:when> <xsl:when test="value and $col"> <fo:table-cell><xsl:value-of select="title"/></fo:table-cell> <fo:table-cell>text</fo:table-cell> </fo:table-row> <xsl:variable name="col" select="''"/> </xsl:when> <xsl:when test="not(value) and not($col)"> <fo:table-row> <fo:table-cell><xsl:value-of select="title"/></fo:table-cell> <fo:table-cell>other text</fo:table-cell> <fo:table-cell number-columns-spanned="2"/> </fo:table-row> </xsl:when> <xsl:when test="not(value) and $col"> <fo:table-cell number-columns-spanned="2"/> </fo:table-row> <fo:table-row> <fo:table-cell><xsl:value-of select="title"/></fo:table-cell> <fo:table-cell>other text</fo:table-cell> <fo:table-cell number-columns-spanned="2"/> </fo:table-row> <xsl:variable name="col" select="''"/> </xsl:when> </xsl:choose> </xsl:for-each> </fo:table-body> \---------------------------------------------------------------------------------------/ This obviously will not work, because XSLT does not allow variables to be reassigned. After reading extensively from O'Reilly's XSLT book and the w3c specs for XSLT and XPath, I decided I could achive my goal with recursive template matches. Here is what I arrived at: /----------------------------------------------------------------------------------------\ <xsl:stylesheet . . .> <xsl:template match="document"> . . . <fo:table-body> <xsl:apply-templates select="field[1]"> </fo:table-body> . . . </xsl:template> <!-- end template match="document" --> <xsl:template match="field"> <xsl:choose> <!-- When current <field> has <value/> and next <field> has <value/> --> <xsl:when test="value and following-sibling::field[1]/value"> <fo:table-row> <fo:table-cell> <!-- current title --> <fo:block><xsl:value-of select="title"/></fo:block> </fo:table-cell> <fo:table-cell> <fo:block>text</fo:block> </fo:table-cell> <fo:table-cell> <!-- next title --> <fo:block><xsl:value-of select="following-sibling::field[1]/title"/></fo:block> </fo:table-cell> <fo:table-cell> <fo:block>text</fo:block> </fo:table-cell> </fo:table-row> <!-- use this template for the next element (after the one previously referred to as 'next'. omitting the final '[1]' will cause this template to be processed remaining <field>, which results in very long files with lots of stuff i don't want. --> <xsl:apply-templates select="following-sibling::field[position() > 1][1]"/> </xsl:when> <!-- if not. . . --> <xsl:otherwise> <fo:table-row> <fo:table-cell> <fo:block><xsl:value-of select="title"/></fo:block> </fo:table-cell> <fo:table-cell number-columns-spanned="3"> <fo:block>other text</fo:block> </fo:table-cell> </fo:table-row> <!-- use this template for the next element. again, don't omit '[1]'. --> <xsl:apply-templates select="following-sibling::field[1]"/> </xsl:otherwise> </xsl:choose> </xsl:template> \------------------------------------------------------------------------------------/ This works great. Based on my understanding of the XSLT parsers, this is pretty memory intensive, as applying "following-sibling::field[1]" actually passes the remaining <field> nodes in <document> every time, leaving a lot of stuff in the stack. Is that correct? At any rate, any ideas on a better way to do this? (Other than a SAX parsing of the XML with a few variables and leaving an extra node in select <field>s.) --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]