What are the correct semantics of a closure over a loop variable? [closed]

Answer 1

There is no "correct" way. There are different ways. In C#, you would fix it by making a variable scoped to the loop:

for (int i = 0; i < 10; i++)
{
    int j = i;

    f[i] = (new Action(delegate()
    {
        Console.Write(j + " ");
    }));
}

In JavaScript, you might add a scope by making and calling an anonymous function:

for (var i = 0; i < 10; i++) {
    (function(i) {
        f[i] = function() {
            document.write(i + ' ');
        };
    })(i);
}

Iteration variables in C# don't have loop scope. JavaScript doesn't have block scope, just function scope. They're just different languages and they do things differently.