Pass ValueTuple instead of arguments

Question

Is it possible to do in this way (or maybe I need specific version of C#)?

Function<int,int,int,int> triSum = (a,b,c) => {return a+b+c;};
var tup = (1,2,3);
triSum(tup); //passing one tuple instead of multiple args

Update: I mean passing tuple instead of separate arguments.

public void DoWrite(string s1, string s2)
{
Console.WriteLine(s1+s2);
}
public (string,string) GetTuple()
{
//return some of them
}
//few lines later
DoWrite(GetTuple());

Answer 1

Yes you could use Named ValueTuples C# 7.1 , or even just a Local Method if it suits

Action<(int a, int b, int c)> triSum = t 
   => Console.WriteLine(t.a + t.b + t.c);

triSum((1, 2, 3));

or just as a local method

void TriSum((int a, int b, int c) t)
   => Console.WriteLine(t.a + t.b + t.c);

TriSum((1, 2, 3));

Answer 2

You can do this:

Func<(int a, int b, int c), int> triSum = x => { return x.a + x.b + x.c; };

var tup = (1, 2, 3);

var sum = triSum(tup);

Or more succinctly this:

Func<(int a, int b, int c), int> triSum = x => x.a + x.b + x.c;

Answer 3

There are some mistakes in the code, in short the following works:

Func<Tuple<int,int,int>,int > triSum = a => { return a.Item1 + a.Item2 + a.Item3; };
Tuple<int,int,int> tup = new Tuple<int, int, int>(3,4,5);
triSum(tup); //passing one tuple instead of multiple args

Problems in the code above:

1. Action is a function delegate which returns void, so you should use Func
2. The way you passed parameters to Action make them three independent ints and not a tuple
3. Also the syntax var tup = (1,2) is from c# 7.0 onwards and cannot be used in older version (a nuget package is there though)