Question

In javascript, it is common to use closures and create then immediately invoke an anonymous function, as below:

var counter = (function() {
    var n = 0;
    return function() { return n++; }
}());

Due to strong typing, this very verbose in C#:

Func<int> counter = ((Func<Func<int>>)(() =>
{
    int n = 0;
    return () => n++;
}))();

Is there a more elegant way to go about this type of thing in C#?

Answer 1

You don’t need the outer lambda in C#, it can be replaced by a simple block.

Directly invoking a lambda is a workaround for the lack of block level variables in Javascript (new versions support block scope using let).

Func<int> counter;

{
     int n = 0;
     counter = () => n++;
}