arrow.kt catch

Author: hoc081098

src/main/kotlin/com/hoc081098/kotlin_playground/arrowkt/catch.kt

@@ -0,0 +1,28 @@
+package com.hoc081098.kotlin_playground.arrowkt
+
+import arrow.core.raise.Raise
+import arrow.core.raise.catch
+import arrow.core.raise.either
+
+data class User(val id: Int, val name: String)
+sealed interface Error {
+  data class UserNotFound(val id: Int) : Error
+}
+
+fun findUserById(id: Int): User =
+  throw NoSuchElementException("User'$id' not found")
+
+context(Raise<Error.UserNotFound>) fun findUserByIdWithRaise(id: Int): User =
+  catch(
+    block = { findUserById(id) },
+    catch = {
+      if (it is NoSuchElementException)
+        raise(Error.UserNotFound(id))
+      else
+        throw it
+    }
+  )
+
+fun main() {
+  println(either { findUserByIdWithRaise(1) })
+}