public void AlternativeParser() { var stream = new MemoryStream <char>("a".AsMemory()); var p1 = Combinator.Alt(Combinator.Char('x'), Combinator.Char('y'), Combinator.Char('z')); var p2 = Combinator.Alt(Combinator.Char('a'), Combinator.Char('b'), Combinator.Char('c')); var r1 = p1.Parse(stream); var r2 = p2.Parse(stream); Assert.False(r1.IsOk); Assert.True(r2.IsOk); Assert.Equal('a', r2.Ok.Value); }