Prado\Collections\TStack::contains PHP Method

    public function contains($item)
    {
        return array_search($item, $this->_d, true) !== false;
    }

 public function testContains()
 {
     $stack = new TStack(array(1, 2, 3));
     self::assertEquals(true, $stack->contains(2));
     self::assertEquals(false, $stack->contains(4));
 }