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trait A { def f() // ந৅ϝιου } ! trait B { def foo() = println("foo") } ! trait C { def bar() = println("bar") } ! class D extends A with B with C { def f() = foo() // ந৅ϝιουΛ࣮૷ˍτϨΠτBͷfooΛݺͼग़͠ override def bar() = { // τϨΠτCͷbarϝιουΛoverride super.bar() // τϨΠτCͷbarϝιουΛݺͼग़͠ println("BAR") } } 

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class Japanese ! trait Kansai ! trait Kanto ! val me = new Japanese with Kansai with Kanto 

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class Animal ! trait HasLegs extends Animal ! trait FourLegged extends HasLegs ! trait Furry extends Animal ! class Cat extends Animal with Furry with FourLegged 

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val q1 = new BasicIntQueue q1.put(10) q1.get() // Int = 10 ! val q2 = new BasicIntQueue with Doubling q2.put(10) q2.get() // Int = 20 ! val q3 = new BasicIntQueue with Doubling with Filtering q3.put(-10) q3.get() // Int = 20 ʰ4DBMBεέʔϥϒϧϓϩάϥϛϯάʱষΑΓ 

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trait Executor { def execute(): Unit } ! trait LoggableExecutor extends Executor { def log(() => Unit):Unit = … abstract override def execute(): Unit { log { super.execute } } } ! class SomeExecutor extends Executor { def execute(): Unit = … } ! val e = new SomeExecutor with LoggableExecutor e.execute 

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trait A { def foo() = “foo” } ! trait B { def bar() = “bar” } ! trait C { this: A with B => def f() = foo + bar } ! val c = new C with A with B c.f // String = foobar 

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class User ! trait UserRepositoryComponent { val repos: UserRepository trait UserRepository { def findById(id: Int): User } } ! class UserService { this: UserRepositoryComponent => def findById(id: Int): User = { repos.findById(id) } } 

trait MySQLUserRepositoryComponent extends UserRepository Component { val repos = new MySQLUserRepository class MySQLUserRepository = { def findById(id: Int): User = … } } ! val userService = new UserService with MySQLUserRepositoryComponent ! val user = userService.findById(1) 

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