/**
* @dataProvider provideData
*/
public function test_it_should_work_with_maybe($list, $expected)
{
$addSingleDigit = function ($acc, $i) {
return $i > 9 ? m\nothing() : m\just($acc + $i);
};
$this->assertEquals($expected, f\foldM($addSingleDigit, 0, $list)->extract());
}
/**
* @dataProvider provideData
*/
public function test_it_should_extract_elements_which_exists_alternative_solution($data)
{
// $get :: String a -> Maybe [b] -> Maybe b
$get = function ($key) {
return f\bind(function ($array) use($key) {
return isset($array[$key]) ? m\just($array[$key]) : m\nothing();
});
};
$result = Listt::of($data)->map(Maybe\maybeNull)->bind($get('meta'))->bind($get('images'))->bind($get(0));
$this->assertEquals(Listt::of([m\just('//first.jpg'), m\just('//third.jpg'), m\nothing()]), $result);
}
public function get($key)
{
return array_key_exists($key, $this->data) ? Maybe\just($this->data[$key]) : Maybe\nothing();
}
public function test_it_traverse_nothing()
{
$list = Listt::of([1, 2, 3, 4]);
$result = f\traverse('example\\value_is', $list);
$this->assertEquals(m\nothing(), $result);
}