[xsl] copy attributes modifying their values, regardless of their names

[TW <zupftom@xxxxxxxxxxxxxx>]

Hi all,

I'm generating XSL stylesheets using XSL.  One thing I want to do is
modify all attribute value templates found in the source document.  I
thought something like this would do the job:

<stylesheet version="1.0" xmlns="http://www.w3.org/1999/XSL/Transform";>
  <template name="modify-attribute-value-templates">
    Create replacement value
  </template>

  <template match="*">
    <copy>
      <for-each select="@*">
        <copy>
          <call-template name="modify-attribute-value-templates"/>
        </copy>
      </for-each>
      <apply-templates/>
    </copy>
  </template>
</stylesheet>

But much to my chagrin I realized that <copy> already copies the value
if applied to attributes.  A workaround could be a long choose element
like this:

  <template match="*">
    <copy>
      <for-each select="@*">
        <choose>
          <when test="not(contains(string(),'{'))">
            <copy/>
          </when>
          <when test="local-name()='att1'">
            <attribute name="att1">
              <call-template name="modify-attribute-value-templates"/>
            </attribute>
          </when>
          <when test="local-name()='att2'">
            <attribute name="att2">
              <call-template name="modify-attribute-value-templates"/>
            </attribute>
          </when>
          <!-- a ton of more attributes -->
          <otherwise>
            <message terminate="yes">
              The attribute value template found in attribute
              <value-of select="local-name()"/>
              isn't handled by the stylesheet.
            </message>
          </otherwise>
        </choose>
      </for-each>
      <apply-templates/>
    </copy>
  </template>

There might be an awful lot of attributes that have to be handled.  If
I don't know what attributes are to be found in the source document,
then I I'll have to add another step to the process, creating the
above choose statement using another stylesheet.

I refuse to believe that something I thought would be done in three
lines turns out to require thousands of lines for case differentiation
and potentially an additional step in the process.  Can anyone help?

Thomas W.