RE: [xsl] Efficient Templating - Concise Template Design

["Michael Kay" <mike@xxxxxxxxxxxx>]

> -----Original Message-----
> From: Adam J Knight [mailto:adam@xxxxxxxxxxxxxxxxx]
> Sent: 21 February 2005 10:02
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject: [xsl] Efficient Templating - Concise Template Design
>
> Hi guys,
>
>
>
> I have created the template below (a part of my first ever complete
> stylesheet). To me it seems a little long winded, and I
> wonder if it could
> be put more concisely. Be a better example of template design.
>

If we take your logic starting at
<xsl:when test="@id = $id or descendant::tree_node/@id = $id">

you seem to have three conditions

A: @id = $id
B: descendant::tree_node/@id = $id
C: $node = 'collapse'

and the decision table is

A   B   C   node     gif

y   ?   y   expand   close
y   ?   n   collapse open
n   y   ?   collapse open
n   n   ?   expand   close

which translates into

if ((A and C) or (not(A) and not(B)))
  then (expand;open)
  else (collapse;close)

I might not have read your logic carefully enough, of course. But it seems
to be essentially a question of simplifying the boolean logic, nothing
specific to XSLT.

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


>
> <xsl:template match="tree_node">
>
>   <tr>
>      <td>
>        <table width="100%">
>          <tr>
>           <td align="right"
> width="{(count(ancestor-or-self::*) - 1) * 20}">
>           <xsl:choose>
>            <xsl:when test="child::tree_node">
>             <xsl:choose>
>              <xsl:when test="@id = $id or
> descendant::tree_node/@id = $id">
>               <xsl:choose>
>                <xsl:when test="@id = $id">
>                  <xsl:choose>
>                    <xsl:when test="$node = 'collapse'">
>                     <a href="{$url}&amp;id={@id}&amp;node=expand">
> <img border="0" width="16" height="16"
> src="images/ui_tree/book_close.gif"/>
>                    </a>
>                    </xsl:when>
>                    <xsl:otherwise>
>                     <a href="{$url}&amp;id={@id}&amp;node=collapse">
>  <img border="0" width="16" height="16"
> src="images/ui_tree/book_open.gif"/>
>                    </a>
>                    </xsl:otherwise>
>                  </xsl:choose>
>                </xsl:when>
>                <xsl:otherwise>
>                  <a href="{$url}&amp;id={@id}&amp;node=collapse">
> <img border="0" width="16" height="16"
> src="images/ui_tree/book_open.gif"/>
>                  </a>
>                </xsl:otherwise>
>              </xsl:choose>
>            </xsl:when>
>            <xsl:otherwise>
>              <a href="{$url}&amp;id={@id}&amp;node=expand">
> <img border="0" width="16" height="16"
> src="images/ui_tree/book_close.gif"/>
>              </a>
>            </xsl:otherwise>
>          </xsl:choose>
>        </xsl:when>
>       <xsl:otherwise>
> <img border="0" width="16" height="16"
> src="images/ui_tree/paper.gif"/>
>       </xsl:otherwise>
>     </xsl:choose>
>     </td>
>     <td>
>       <a href="{$url}&amp;page={@id}">
>         <xsl:value-of select="@value"/>
>       </a>
>     </td>
>     <td align="right" width="5%">
>       <a href="{$url}&amp;action=edit&amp;node={@id}">edit</a>
>     </td>
>     <td align="right" width="5%">
>       <a href="{$url}&amp;action=delete&amp;node={@id}"
> onClick="return
> deleteConfirm();">delete</a>
>     </td>
>   </tr>
> </table>
> </td>
> </tr>
> </xsl:template>
>
> Cheers,
>
> Adam
>
>
>
>
>
> Cheers,
> Adam
>  
> NB: "Pray as if everything depended upon God and work as if everything
> depended upon man."