寻求帮助'@property(nonnull)'是什么? [英] For help '@property (nonnull)' what it is?

问题描述

@property(非null).iOS8.3中是否添加了 nonnull ，它能做什么?

@property (nonnull) . Does nonnull added in iOS8.3 and what can it do?

推荐答案

是的，它已在XCode 6.3中添加

Yes , it is added in XCode 6.3

从此处(nshipster)

nonnull:指示指针应该/永远不会为nil.用nonnull注释的指针作为其指针导入到Swift中非可选的基础值(即NSData).

nonnull: Indicates that the pointer should/will never be nil. Pointers annotated with nonnull are imported into Swift as their non-optional base value (i.e., NSData).

还有其他两个相似的属性

There are also other two similar properties

• null_resettable

表示虽然属性将始终具有值，但它可以是通过分配nil重置.具有非零默认值的属性可以是这样注释，就像tintColor一样.导入到Swift作为一个(相对安全)隐式展开的可选内容.

Indicates that while a property will always have a value, it can be reset by assigning nil. Properties with a non-nil default value can be annotated this way, like tintColor. Imported into Swift as a (relatively safe) implicitly unwrapped optional.

• 可空

表示一般情况下指针可以为nil.进口的进入Swift作为可选值

Indicates that the pointer can be nil in general practice. Imported into Swift as an optional value

• null_unspecified

继续当前作为隐式解包的可选，理想情况下在此过程中使用仅限注释过程.

Continues the current functionality of importing into Swift as an implicitly unwrapped optional, ideally to be used during this annotation process only.

您可以查看在XCode中与null相关的属性可以吗?

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