2 定义一个他的子类,这个子类必须定义在同一个文件中 3 在这个方法中,when 表达式 不需要定义 else 的字段,是因为穷举了 所有的可能性,这里有人会问了Mammal 不算嘛,其实是因为你创建不出来 Mammal 这个类,7这里会报错Cannot access '<init>': it is private in 'Mammal' Sealed types cannot be instantia...
Inheritor of sealed class or interface declared in package xxx but it must be in package xxx where base class is declared sealed class 还具有如下特点或限制: sealed class 是抽象类,可以拥有抽象方法,无法直接实例化。否则,编译器将提示如下: Sealed types cannot be instantiated sealed class 的构造函数...
sealed interface Actionenum class GameAction : Action {Start, Exit, Restart}enum class BirdAction : Action {Up, Down, HitGround, HitPipe, CrossedPipe}enum class PipeAction : Action {Move, Reset}enum class RoadAction : Action {Move, Reset}object Tick: Action 使用的时候就可以对抽成的 Action...
Inheritor of sealed class or interface declared in package xxx but it must be in package xxx where base class is declared sealed class 还具有如下特点或限制: sealed class 是抽象类,可以拥有抽象方法,无法直接实例化。否则,编译器将提示如下: Sealed ...
KT-59711 K/N: Implement enumEntries intrinsic KT-60154 K2: Expected some types error KT-58139 K2/MPP/metadata: compiler FIR serialization crash on complex expression as annotation argument KT-59485 K2: build Anki-Android KT-59415 K2: Missing DATA_CLASS_OVERRIDE_DEFAULT_VALUES_ERROR KT-59710 K...
KT-58126 Wasm: Consider removing Primitive.equals(Primitive) overload on primitive types KT-53327 Migrate all usages of 'Enum.values' to 'Enum.entries' in standard library KT-59366 Deprecate KmModule.annotations KT-59365 Get rid of two-stage parsing in KotlinClassMetadata KT-35116 Enum.valueOf...
A sealed class is used for representing restricted class hierarchies. A value can have one of the types from a limited set, but cannot have any other type. Sealed classes are more powerful enum classes. Note:in some languages, such as C# or Scala, a sealed class is a class which prohibi...
Asealed classis used for representing restricted class hierarchy where an object or a value can have one of the types from a limited set of values. You can think of a sealed class as an extension of enum class. The set of values in enum class is also restricted, however an enum constant...
The advantage of having a common function for all types is that we don't have to type check using theisoperator. We can simply use polymorphism as shown in theDeliveryManagerclass of enum example. Inheritance Enum Sinceenumvalues are objects, they cannot be extended: ...
Sealed classes allow you to create a strictly defined class hierarchy that is similar to an enum class but that allow multiple instances of each subtype to be created and hold state. Secondary constructors allow you to define additional constructors that take additional parameters than the primary...