The concatenation of lists is denoted by [ , ]:
Prototype
list <-- [ list , list [, list]* ]
Note that since elements are lists of length one, elements can be concatenated to lists.
Examples
global $d = select top DATE within $h from $h in (top HEAD within file $myfile) ;global $n = select top NUM within $h from $h in (top HEAD within file $myfile) ;[$d , $n ];<DATE> 16 July 1991 </DATE><DATE> ...(full result)...