Unexpected behavior of Query.jl @map

query

#1

I tried to call a function for each selected row with Query.jl with the following code:

test = DataFrame()
test[:a] = [1,2,3,4]
test[:b] = [1,1,2,3]
test |> @filter(_.b==1) |> @map(println(_.a))

and I noticed that in Juno and in the REPL the function is evaluated more than once for each value as the console output is

julia> 1
2
1
2

for Juno and

julia> test |> @filter(_.b==1) |> @map(println(_.a))
?-element query result
1
 1nothing

2
2
 nothing

for the REPL. Beside the fact that I did not expect the function to be evaluated more than once per value I noticed that in Jupyter it seems that it is evaluated only once per value:

Is this behavior intended?