some syntactical ideas for C#

syntax.cs

class Example
{
    // "init-anywhere" syntax (along the lines of Haskell)
    [Implemented(true)]
    Foo Do()
    {
        var x = new Foo { bar = 1 }; // <- currently available
        return x { bar = 3 }; // <- proposed (note that this mutates unlike Haskell)
    }
    
    [Implemented(true)]
    Foo Also()
    {
        var x = new Foo { bar = 1 };
        
        // this could be used akin to VB 'with' ;)
        x {
            bar = 2,
            baz = 3,
        };
        
        return x;
    }
    
    // And for Java-parity:
    // - reuse keyword 'where' to do anonymous inner classes (it's needed to disambig)
    public void YEAH()
    {
        var x = new Foo { bar = 1 }
                where
                {
                    public override string ToString()
                    {
                        Console.WriteLine("HAHA!");
                    }
                };
    }
    
    // without 'where' there'd some some ambiguity when parsing collection initializers
    List<int> DisambigRequired()
    {
        // also, methods should default to "public" inside wheres
        // not private!
        return new List<int> where { int Length { return Count; } }
    }
    
    // also implement new interfaces
    IDisposable Whatever()
    {
        // how about:
        
        return new List<int> where IDisposable { void Dispose() { Console.WriteLine("Disposed"); } }
    }
    
    // combine these features:
    void FairlyTerribleCode<T>()
    {
        var magicList = new List<T> where {
            List<T> GetValueOrDefault(T elseWise)
            {
                if (Count == 0) Add(elseWise);
                return this;
            }
        }
        
        var stupidity = (magicList ?? default(T)).First();
    }
    
    // tuple unpacking
    void EveryoneKnowsThisAlready()
    {
        var (x, y, z) = Tuple.Create(1, 2, 3);
        
        // expands to:
        var tmp = Tuple.Create(1, 2, 3);
        var x = tmp.Item1;
        var y = tmp.Item2;
        var z = tmp.Item3;
    }
    
    // tuple syntax
    [Implemented(true)]
    void ALaPython()
    {
        var x = (1, 2, 3);
        var y = (1, 2);
        var z = (1,);
    }
    
    // and in return types:
    [Implemented(true)]
    (int, string) Foo()
    {
        return (1, "hello");   
    }
    
    
    
    /* and a few more items; */
    void Misc()
    {
        // default-assign operator
        int? x = null;
        x ??= 2;
        
        // binary literals
        var n = 0b1010;
    }
}