/**
 * Function : dump()
 * Arguments: The data - array,hash(associative array),object
 *    The level - OPTIONAL
 * Returns  : The textual representation of the array.
 * This function was inspired by the print_r function of PHP.
 * This will accept some data as the argument and return a
 * text that will be a more readable version of the
 * array/hash/object that is given.
 * Docs: http://www.openjs.com/scripts/others/dump_function_php_print_r.php
 */
function dump(arr,level) {
	var dumped_text = "";
	if(!level) level = 0;

	//The padding given at the beginning of the line.
	var level_padding = "";
	for(var j=0;j "" + value + ""n";
			}
		}
	} else { //Stings/Chars/Numbers etc.
		dumped_text = "===>"+arr+"<===("+typeof(arr)+")";
	}
	return dumped_text;
}

//Calling the function...
function init() {
	var arra = new Array("So long",'s',42,42.13,"Hello World");
	var assoc = {
		"val"  : "New",
		"number" : 8,
		"theting" : arra
	};

	alert(dump(assoc));
}
window.onload=init;

'val' => "New"
'number' => "8"
'theting' ...
   '0' => "So long"
   '1' => "s"
   '2' => "42"
   '3' => "42.13"
   '4' => "Hello World"

Forrás: http://www.openjs.com/scripts/others/dump_function_php_print_r.php