-- main.mcl --
import "fmt"

$map1 = {0 => "a", 1 => "b", 2 => "c",}
$map2 = {"x" => 42, "y" => 13, "z" => -4,}

forkv $key1, $val1 in $map1 {
	forkv $key2, $val2 in $map2 {

		$s = fmt.printf("%s is %d", $val1, $val2)
		test [$s,] {}
	}
}

-- OUTPUT --
Vertex: test[a is 42]
Vertex: test[b is 42]
Vertex: test[c is 42]
Vertex: test[a is 13]
Vertex: test[b is 13]
Vertex: test[c is 13]
Vertex: test[a is -4]
Vertex: test[b is -4]
Vertex: test[c is -4]