OK.apply method to account for OK(Err(_))

Author: odersky

library/src/scala/magic/Ok.scala

@@ -1,14 +1,13 @@
 package scala.magic
 
-import scala.magic.runtime.Valid
+import scala.magic.runtime.{MaybeCase, Valid}
 import scala.magic.compiletime.Maybe
 import annotation.experimental
 
 @experimental
 object Ok:
   inline def apply[T](x: T): Maybe[T, Nothing] = {
-    if x == null then new Valid(null)
-    else if x.isInstanceOf[Valid] then new Valid(x)
+    if x == null || x.isInstanceOf[MaybeCase] then new Valid(x)
     else x
   }.asInstanceOf[Maybe[T, Nothing]]
 

library/src/scala/magic/runtime/Fail.scala

@@ -3,4 +3,4 @@ package scala.magic.runtime
 import annotation.experimental
 
 @experimental
-case class Fail[+E](elem: E)
+case class Fail[+E](elem: E) extends MaybeCase

library/src/scala/magic/runtime/MaybeCase.scala

@@ -0,0 +1,7 @@
+package scala.magic.runtime
+
+import annotation.experimental
+
+@experimental
+abstract class MaybeCase
+

library/src/scala/magic/runtime/Valid.scala

@@ -3,4 +3,4 @@ package scala.magic.runtime
 import annotation.experimental
 
 @experimental
-case class Valid(elem: Any)
+case class Valid(elem: Any) extends MaybeCase

tests/run-tasty-inspector/stdlibExperimentalDefinitions.scala

@@ -113,6 +113,7 @@ val experimentalDefinitionInLibrary = Set(
   "scala.magic.runtime.Fail$",
   "scala.magic.runtime.Valid",
   "scala.magic.runtime.Valid$",
+  "scala.magic.runtime.MaybeCase",
 )
 
 

tests/run/ok-tostring.check

@@ -0,0 +1,3 @@
+Valid(null)
+Valid(Fail(bad))
+good

tests/run/ok-tostring.scala

@@ -0,0 +1,10 @@
+//> using options -Yexplicit-nulls
+import language.experimental.magic
+import language.future
+import scala.magic.*
+
+@main def Test =
+  println(Ok(null))
+  println(Ok(Err("bad")))
+  println(Ok("good"))
+