IOApp.ResourceApp

core/js/src/main/scala/cats/effect/IOApp.scala

@@ -28,7 +28,7 @@ trait IOApp {
   protected def runtimeConfig: unsafe.IORuntimeConfig = unsafe.IORuntimeConfig()
 
   def run(args: List[String]): IO[ExitCode]
-
+  
   final def main(args: Array[String]): Unit = {
     if (runtime == null) {
       import unsafe.IORuntime

core/jvm/src/main/scala/cats/effect/IOApp.scala

@@ -139,6 +139,7 @@ trait IOApp {
         Thread.currentThread().interrupt()
     }
   }
+
 }
 
 object IOApp {

core/shared/src/main/scala/cats/effect/ResourceApp.scala

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2020-2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package cats.effect
+
+import cats.syntax.all._
+
+trait ResourceApp { self =>
+  def run(args: List[String]): Resource[IO, ExitCode]
+
+  final def main(args: Array[String]): Unit = {
+    val ioApp = new IOApp {
+      override def run(args: List[String]): IO[ExitCode] =
+        self.run(args).use(IO.pure(_))
+    }
+
+    ioApp.main(args)
+  }
+}
+
+object ResourceApp {
+  trait Simple extends ResourceApp {
+    def run: Resource[IO, Unit]
+    final def run(args: List[String]): Resource[IO, ExitCode] = run.as(ExitCode.Success)
+  }
+
+  trait Forever { self =>
+    def run(args: List[String]): Resource[IO, Unit]
+
+    final def main(args: Array[String]): Unit = {
+      val ioApp = new IOApp {
+        override def run(args: List[String]): IO[ExitCode] =
+          self.run(args).useForever
+      }
+
+      ioApp.main(args)
+    }
+  }
+}