邁向一萬小時成長之路: nil & NULL

2014年4月24日星期四

節錄自http://nshipster.com/nil/

Symbol	Value	Meaning
`NULL`	`(void *)0`	literal null value for C pointers
`nil`	`(id)0`	literal null value for Objective-C objects
`Nil`	`(Class)0`	literal null value for Objective-C classes
`NSNull`	`[NSNull null]`	singleton object used to represent null

邁向一萬小時成長之路