应用所有这些 Scala 特性在运行时会产生什么样的影响？
想象一下：
val myObject = if(someCondition) {
new Whatever with Trait1
} else if(otherCondition) {
new Whatever with Trait2 with Trait3 with Trait4
} else {
new Whatever with Trait5
}
myObject 对象是在运行时“组合”的，还是 scala 编译器足够智能，可以在编译时生成适当的代码？如果您有多个地方应用上述代码中的特征，会对代码产生什么样的性能影响？
Imagine this:
val myObject = if(someCondition) {
new Whatever with Trait1
} else if(otherCondition) {
new Whatever with Trait2 with Trait3 with Trait4
} else {
new Whatever with Trait5
}
Is the myObject object "composed" at runtime, or is the scala compiler smart enough to generate the appropriate code at compile time? What kind of performance impact will it have on the code if you have multiple places that are applying traits like in the above code?
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它是在编译时组成的。
特征将作为接口添加到结果类型中，并且这些特征中的任何具体方法（通常）将被完整复制到类中。
有时，编译器可能必须通过静态方法的转发器提供具体的实现，但通常情况并非如此。
It's composed at compile-time
The traits will be added as interfaces to the resulting type, and any concrete methods from those traits will (usually) be copied to the class in their entirety.
Occasionally, the compiler may have to provide concrete implementations via forwarders to static methods, but this isn't usually the case.
Scala 将创建三个匿名类（除了最后一个条件是语法错误）。
注意：这些类将使用它们在定义范围内定义的顺序来命名。所以... OuterClass$anon$1 -> 3. 请避免在任何长期 Java 序列化中使用这些匿名类，因为这会锁定代码中匿名类的顺序。
除此之外，这是一个很棒的便利功能！
Scala will create three anonymous classes, (except the last condition is a syntax error).
Note: These classes will be named using the order in which they are defined in the scope they are defined. So... OuterClass$anon$1 -> 3. Please avoid using these anonymous classes in any long-term Java-serialization as this locks down the order of anonymous classes in your code.
Other than that, it's an awesome convenience feature!