Reliably determine the type of a variable in node.js

getVariableType.js

function getType (thing) {
	switch (Object.prototype.toString.call(thing)) {
		
		case '[object Object]':
			return 'object'
		break		

		case '[object Array]':
			return 'array'
		break

		case '[object String]':
			return 'string'
		break

		case '[object Number]':
			return 'number'
		break		

		case '[object Boolean]':
			return 'number'
		break

		case '[object Null]':
			return 'null'
		break
	}
}