/**
 * String escape function.
 */
function h (s)
{
	return s.toString().replace (/&/g, "&amp;").replace (/</g, "&lt;").replace (/>/g, "&gt;")
}

/**
 * Returns first non-null and non-undefined argument or undefined if not found.
 */
function coalesce()
{
	return $A(arguments).find (function (argument) {
		return typeof argument !== 'undefined' && argument !== null
	})
}