iter\IterTest::testChain PHP 메소드

    public function testChain()
    {
        $chained = chain(range(1, 3), range(4, 6), range(7, 9));
        $this->assertSame([1, 2, 3, 4, 5, 6, 7, 8, 9], toArray($chained));
        // empty chain
        $this->assertSame([], toArray(chain()));
    }