Synopsis

<xsl:template match="sgmltag">
<xsl:param name="class">
			<xsl:choose>
				<xsl:when test="@class">
					<xsl:value-of select="normalize-space(@class)"/>
				</xsl:when>
				<xsl:otherwise>element</xsl:otherwise>
			</xsl:choose>
		</xsl:param>
  ...
</xsl:template>