-- main.mcl --
import "golang"
import "iter"

# Empty inner lists are dropped; empty outer list yields the empty list.
$lists1 = [[], ["a", "b"], [], ["c"], []]
$out1 = iter.flatten($lists1)

$lists2 [][]int = []
$out2 = iter.flatten($lists2)

$t1 = golang.template("out1: {{ . }}", $out1)
$t2 = golang.template("out2: {{ . }}", $out2)

test "${t1}" {}
test "${t2}" {}
-- OUTPUT --
Vertex: test[out1: [a b c]]
Vertex: test[out2: []]
