Javascript: Closure Function

A simple example of a closure in Javascript. It demonstrates how the returned function maintains access to the variables defined in the function that defined the returned function (is this an infinite loop description).

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function closure__get_display_name_logger(name)
{
    var display_name = "User: " + name;

    var display_name_logger = function log_display_name()
    {
        console.log(display_name);
    }

    //function returns a function
    return display_name_logger;
}

//save returned function
var display_name_logger = closure__get_display_name_logger("Homer");

//use returned function
//the display name variable is maintained, "closed" within the function
display_name_logger();



//this will return a function and the the returned function will always have access to the counter variable
function closure__get_counter_logger()
{
    var counter = 0;

    var counter_logger = function log_counter()
    {
        counter++;
        console.log(counter);
    }

    return counter_logger;
}

//function returns a function
var counter_logger = closure__get_counter_logger();

//use returned function
//the returned function still has access to the counter variable
counter_logger(); //1
counter_logger(); //2
counter_logger(); //3
counter_logger(); //4
counter_logger(); //5