function checkValue (val, expectedType, name) {
	if (typeof val !== expectedType) {
		throw new Error(name + ' must return ' + expectedType);
	}
	return Utils;
}
function checkValue (val, expectedType, name) {
	if (typeof val !== expectedType) {
		throw new Error(name + ' must return ' + expectedType);
	}
	return Utils;
}
function checkValue ( val , expectedType , name ) { if ( typeof val !== expectedType ) { throw new Error ( name + ' must return ' + expectedType ) ; } return Utils ; }
/* Utils.check.value();
Utils.check.fn();
Test typeof of a returned value
or of a single value
/ * Utils . check . value () ; Utils . check . fn () ; Test typeof of a returned value or of a single value