function testIntegratedFilterMap()
{
$numbers = new qinq\Collection(range(1, 10));
$matches = [1, 27, 125, 343, 729];
// only odd numbers
foreach ($numbers->filter(function ($v) {
return (bool) ($v & 1);
})->map(function ($v) {
return $v * $v * $v;
}) as $number) {
$this->assertEquals(1, $number & 1);
$match = array_shift($matches);
$this->assertEquals($match, $number);
}
}
