Expression-bodied function members allow methods, properties and other kinds of function members to have bodies that are expressions instead of statement blocks, just like with lambda expressions.

Methods as well as user-defined operators and conversions can be given an expression body by use of the “lambda arrow”:

public Point Move(int dx, int dy) => new Point(x + dx, y + dy); 
public static Complex operator +(Complex a, Complex b) => a.Add(b); 
public static implicit operator string(Person p) => "\{p.First} \{p.Last}";

The effect is exactly the same as if the methods had had a block body with a single return statement.

For void returning methods – and Task returning async methods – the arrow syntax still applies, but the expression following the arrow must be a statement expression (just as is the rule for lambdas):

public void Print() => Console.WriteLine(First + " " + Last);

Properties and indexers can have getters and settersgetter-only properties and indexers can have an expression body:

public string Name => First + " " + Last; 
public Customer this[long id] => store.LookupCustomer(id);

with(obj1, obj2){
    .member1 = .member2 * 10;
}

B>with(obj1, obj2){
B>    .member1 = .member2 * 10;
B>}
B>

using System.Coinsole;
class Prog
{
  static void Main()
  {
    var obj1 = new Obj1();
    using obj1;

    WriteLine(member1);
  }
}

B> чем вот эта помойка, которую они сделают из функций и названий классов. Почему проектировщики такие индусы?? Неужто НИЧЕГО не кликает в башке, когда явно совесть подзуживает?

Note: The Preview will only import members of static classes. We have since changed the design in several ways:
1. The syntax will be more different from current using clauses – it will have the keywords “using static”.
2. Members of non-static types can be imported, including structs and enums
3. Members of VB modules and F# top level functions can be imported
4. Extension methods will not be imported into top-level scope; instead they will show up as extension methods. This gives a way to import extension methods from just a single class, something which wasn’t possible before.

public Point Move(int dx, int dy) => new Point(x + dx, y + dy); 
public static Complex operator +(Complex a, Complex b) => a.Add(b); 
public static implicit operator string(Person p) => "\{p.First} \{p.Last}"; // в следующем релизе будет $"{p.First} {p.Last}"

try
{
    try
    {
        Run();
    }
    catch (Exception1 err1)
    {
        ...
    }
}
catch (Exception2 err2)
{
    ...
}