Playground

import System;

// A block body.
Gcd(i64 a, i64 b) : i64
{
	loop (b != 0)
	{
		i64 t = a % b;
		a = b;
		b = t;
	}
	return a;
}

// An expression body.
Square(i32 x) : i32 => x * x;

// No result: the function returns nothing.
Report(str label, i64 value)
{
	Console.WriteLine(label + ": " + value);
}

Main()
{
	Report("gcd", Gcd(84, 36));
	Report("square", Square(9));
}