The operator forall...in returns TRUE if
- for each element variable1 in list1
- for each element variable2 in list2
- etc.
the query boolean is true.
Prototype
boolean <-- forall variable1 in list1 , [variable2 in list2]* : boolean Examples
forall $d in (top DATE within file $myfile): text($d) match "1992"; FALSE
Note that the evaluation stops at the first tuple for which boolean is false. The computation can be expensive for large lists, since in the worst case, the entire cartesian product of list1, list2, etc. is computed.