xsl string-join() multiple variables - only use non-empty
问题 I'd like to create several xsl:variable that may or may not be null then join them: <xsl:variable name="creatorType" select="replace(lib:merge(subfields/subfield[matches(@code,'[e]')],' '),'author|[.$]','')" /> <xsl:variable name="creatorAttribution" select="replace(lib:merge(subfields/subfield[matches(@code,'[j]')],' '),'[,-.]$','')" /> <xsl:variable name="creatorNameFullForm" select="replace(lib:merge(subfields/subfield[matches(@code,'[q]')],' '),'[,-()]$','')" /> <xsl:variable name=