public function testCurryN()
{
$sum2 = function ($a, $b) {
return $a + $b;
};
$curriedSum2 = P::curryN(2, $sum2);
$addToFive = $curriedSum2(5);
$this->assertEquals(8, $addToFive(3));
$this->assertEquals(8, $curriedSum2(3, 5));
$sum3 = function ($a, $b, $c) {
return $a + $b + $c;
};
$curriedSum3 = P::curryN(3, $sum3);
$plus5 = $curriedSum3(5);
$plus10 = $plus5(10);
$minus4 = $plus10(-4);
$this->assertEquals(11, $minus4);
$this->assertEquals(11, $plus5(10, -4));
}