Question

Is there any way to break a closure easily in JavaScript? The closest I have gotten is this:

var src = 3;
function foo () {
    return function () {
        return src; }
    }
function bar (func) {
    var src = 9;
    return eval('('+func.toString()+')')(); // This line
}
alert(bar(foo()));

This prints ‘9’, instead of ‘3’, as a closure would dictate. However, this approach seems kind of ugly to me, are there any better ways?

Answer 1

As others said this doesn’t seem to be the right thing to do. You should explain why you want this and what you want to achieve.

Anyway, one possible approach could be to access properties of an object inside your function. Example:

var src = 3;

function foo (context) {
    context = context || window; // Fall back to the global namespace as default context

    return function () {
        return context.src; 
    }
}

function bar (func) {
    var context = {src: 9};
    return func(context);
}

alert(bar(foo));