public void FantasyBird_Bluebird_() { FantasyBirds.Bluebird_ <int, int, int, int>(x => y => x * y)(2)(x => x + 1)(2) .ShouldBe(6); FantasyBirds.Bluebird_ <string, string, string, string>(x => y => $"{x} {y}")("Hello")(x => x.ToUpper())("World") .ShouldBe("Hello WORLD"); }