public function testChain()
{
$addTwo = function ($x) {
return Either::of($x + 2);
};
$id = function ($x) {
return $x;
};
$a = Either::of(5);
$b = new Left(4);
$this->assertEquals($a->chain($addTwo)->either($id, $id), 7, 'Chains a Right.');
$this->assertEquals($b->chain($addTwo)->either($id, $id), 4, 'Chains a Left.');
}
public function testAp()
{
$addTwo = Either::of(function ($x) {
return $x + 2;
});
$id = function ($x) {
return $x;
};
$a = Either::of(5);
$b = new Left(4);
$this->assertEquals($addTwo->ap($a)->either($id, $id), 7, 'Applies to a Right.');
$this->assertEquals($addTwo->ap($b)->either($id, $id), 4, 'Applies to a Left.');
}
