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scala · May 9, 2022 · cc44db8 · cc44db8
1 parent bb3dbf7
commit cc44db8
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/library/src/scala/runtime/stdLibPatches/Predef.scala b/library/src/scala/runtime/stdLibPatches/Predef.scala
@@ -50,6 +50,9 @@ object Predef:
   extension [T](x: T | Null) inline def nn: x.type & T =
     scala.runtime.Scala3RunTime.nn(x)
 
+  /** Enables an expression of type `T|Null`, where `T` is a subtype of AnyRef, to be checked for `null`
+   *  using `eq` and `ne`, rather than only `==` and `!=`. This is needed because `Null` no longer has
+   *  `eq` or `ne` methods, only `==` and `!=` inherited from `Any`. */
   extension (inline x: AnyRef | Null)
     @experimental
     inline def eq(inline y: AnyRef | Null): Boolean =