TaskApp

Safe App type that executes a Task. Shutdown occurs after the Task completes, as follows:

- If completed with ExitCode.Success, the main method exits and shutdown is handled by the platform.

- If completed with any other ExitCode, sys.exit is called with the specified code.

- If the Task raises an error, the stack trace is printed to standard error and sys.exit(1) is called.

When a shutdown is requested via a signal, the Task is canceled and we wait for the IO to release any resources. The process exits with the numeric value of the signal plus 128.

import cats.effect._
import cats.implicits._
import monix.eval._

object MyApp extends TaskApp {
  def run(args: List[String]): Task[ExitCode] =
    args.headOption match {
      case Some(name) =>
        Task(println(s"Hello, \${name}.")).as(ExitCode.Success)
      case None =>
        Task(System.err.println("Usage: MyApp name")).as(ExitCode(2))
    }
}

N.B. this is homologous with cats.effect.IOApp, but meant for usage with Task.

Works on top of JavaScript as well ;-)

Linear Supertypes

AnyRef, Any

Abstract Value Members

abstract def run(args: List[String]): Task[ExitCode]

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0

Definition Classes
Any
implicit lazy val catsEffect: ConcurrentEffect[Task]

Provides the cats.effect.ConcurrentEffect instance of this runtime environment.
Provides the cats.effect.ConcurrentEffect instance of this runtime environment.

Attributes
protected
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def main(args: Array[String]): Unit
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
def options: Options

Options for executing the Task action.
Options for executing the Task action. The default value is defined in defaultOptions, but can be overridden.

Attributes
protected
def scheduler: Scheduler

Scheduler for executing the Task action.
Scheduler for executing the Task action. Defaults to global, but can be overridden.

Attributes
protected
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )

Related Doc: package eval

trait TaskApp extends AnyRef

Abstract Value Members

abstract def run(args: List[String]): Task[ExitCode]

Concrete Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

implicit lazy val catsEffect: ConcurrentEffect[Task]

def clone(): AnyRef

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

final def main(args: Array[String]): Unit

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

def options: Options

def scheduler: Scheduler

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

Inherited from AnyRef

Inherited from Any

Ungrouped