declare function local:Construct ($id) { <tag id="{$id}"/> }
for $val in ... ... return local:Construct(data($val/id))
for $val in ... ... return local:Construct(data($val/id1)) + local:Construct(data($val/id2))
,在这种情况下,您要使用 ,
for $val in ... ... return (local:Construct(data($val/id1)), local:Construct(data($val/id2)))
local:Construct(data($val/id2))