Why don't Funcs accept more than 16 arguments?

Question

Since Javascript is the language that I am the most proficient at, I am familiar with using functions as first-class objects. I had thought that C# lacked this feature, but then

Answer 1

You can just define any delegate you need. So a Func with 20 parameters would be defined like this:

public delegate R Func<
    P0, P1, P2, P3, P4, P5, P6, P7, P8, P9,
    P10, P11, P12, P13, P14, P15, P16, P17, P18, P19, R>(
        P0 p0, P1 p1, P2 p2, P3 p3, P4 p4,
        P5 p5, P6 p6, P7 p7, P8 p8, P9 p9,
        P10 p10, P11 p11, P12 p12, P13 p13, P14 p14,
        P15 p15, P16 p16, P17 p17, P18 p18, P19 p19);

You could then use it like this:

Func<
        int, int, int, int, int, int, int, int, int, int,
        int, int, int, int, int, int, int, int, int, int, int> f = (
            p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, p10,
            p11, p12, p13, p14, p15, p16, p17, p18, p19) =>
                p0 + p1 + p2 + p3 + p4 + p5 + p6 + p7 + p8 + p9 + p10
                    + p11 + p12 + p13 + p14 + p15 + p16 + p17 + p18 + p19;

var r = f(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1);

C# also lets you use lambda syntax on any delegate, so you could also do this:

public delegate R ArrayFunc(params P[] parameters);

And then use it like so:

ArrayFunc af = ps => ps.Sum();

var ar = af(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1);

It's a very flexible and powerful feature of the language.