我正在使用Saxon处理器来执行验证。包含所有函数定义的文件如下:default-definition.txt:declarevariable$aexternal;declarevariable$bexternal;declarevariable$cexternal;declarefunctioniaf:sum($paramsasitem()*)asitem()+{let$facts:=if(empty($params))then(0)elseone-or-more($params)let$values:=for$iin$factsreturn(iaf:splitValueThresh