Returning Lists of Tuples

tuple content is introduced with '('

return ("rumsti", "ramsti")

this is only a single tuple value, tuple content is basic or aggregate

forall [ $a (slide) ]
return
    ("rumsti", $a)

default evaluation context in a tuple is string, everything would be converted into a string

override the evaluation context to return items using {}

forall [ $a (slide) ]
return
    ( { $a }, "rumsti")