exception_handler.js

var try_it = function(exception_logger) {
	try {
		fib_recursive(-1);
	} catch(e) {
		exception_logger.log(e.name, e.message);
	}
}

function fib_recursive(n) {
	if (n < 0) {
		throw {
			name: 'Invalid Argument',
			message: 'Fib needs positive number'
		};
	}
	return (n <= 1) ? n : fib_recursive(n - 1) + fib_recursive(n - 2);
};