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// this won't compile
trait Language(name: String)

// Use abstract class when needs to have constrctor arguments
abstract class Language(name: String)

erangaeb

trait Language {
  // abstract
  var name: String
  
  // concrete
  val maxUsage = 10     
  
  // abstract
  def lang(): Unit         
  

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trait Language {
  def lang(): Unit
}

trait Functional extends Language {
  override def lang() {
    println("Functional")
  }
}

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trait Lambda {
  val l = "Lambda"
}

trait Calculus {
  this: Lambda =>
  val c = "Calculus"
  val lc = l + c
}

erangaeb

trait Lambda {
  val l = "Lambda"
}

trait Calculus extends Lambda {
  val c = "Calculus"
  val lc = l + c
}

erangaeb

trait EmployeeDbComp {
  
  val employeeDb: EmployeeDb
  
  trait EmployeeDb {
    def createEmployee(employee: Employee)
    def getEmployee(empId: Int): Employee
  }
  
}

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trait CassandraEmployeeDbComp extends EmployeeDbComp {

  this: CakezCassandraCluster =>

  val employeeDb = new CassandraEmployeeDb

  class CassandraEmployeeDb extends EmployeeDb {

    def logger = LoggerFactory.getLogger(this.getClass)

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trait EmployeeServiceComp {

  val Service: EmployeeService

  trait EmployeeService {
    def POST(employee: Employee): Future[Unit]
    def GET(id: Int): Future[Employee]
  }

}

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trait SprayEmployeeServiceCompImpl extends EmployeeServiceComp with Configuration {

  this: CakezActorSystem =>

  val employeeService = new SprayEmployeeService

  class SprayEmployeeService extends EmployeeService {

    def logger = LoggerFactory.getLogger(this.getClass)

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class EmployeeHandler {

  this: EmployeeDbComp with EmployeeServiceComp =>

  def logger = LoggerFactory.getLogger(this.getClass)

  def createEmployee(inputEmp: String): Employee = {
    // inputEmp comes as 'emp_id name department'
    val tokens = inputEmp.split(" ")