In C++ I can define a constructor and destructor explicitly, and then cout << C or D Called from with in the constructor/destructor function, to know exactly where.

However in JavaScript how do I know when an object is destructed. The example below is the case that concerns me.

I'm calling an internal function on a timeout and I'm wondering if the object stays alive as long as the timer is running, waiting to call next again.

User Click calls Control

// Calls  Control

Control calls Message

var message_object = new Message( response_element );

Message calls Effects

new Effects().fade( this.element, 'down', 4000 );

message_object.display( 'empty' );

Effects

/**

 *Effects - build out as needed

 *  element - holds the element to fade

 *  direction - determines which way to fade the element

 *  max_time - length of the fade

 */



var Effects = function(  ) 

{

    this.fade = function( element, direction, max_time ) 

    {

        element.elapsed = 0;

        clearTimeout( element.timeout_id );

        function next() 

        {

            element.elapsed += 10;

            if ( direction === 'up' )

            {

                element.style.opacity = element.elapsed / max_time;

            }

            else if ( direction === 'down' )

            {

                element.style.opacity = ( max_time - element.elapsed ) / max_time;

            }

            if ( element.elapsed <= max_time ) 

            {

                element.timeout_id = setTimeout( next, 10 );

            }

        }

        next();

    }

};