Error in Scala compiler: unexpected opening parenthesis

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think I've found the smallest piece of code that chokes the compiler!

class A(implicit a: A)()

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Imported From: https://issues.scala-lang.org/browse/SI-8704?orig=1
Reporter: Krasimir Georgiev (comco)
Affected Versions: 2.11.1

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@som-snytt said:
You can make it shorter by leaving off the closing paren.

scala.reflect.internal.FatalError: unexpected opening parenthesis

Because of the implicit, it stopped consuming param lists.

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@som-snytt said:
Previously,

Welcome to Scala version 2.9.3 (OpenJDK 64-Bit Server VM, Java 1.6.0_34).
Type in expressions to have them evaluated.
Type :help for more information.

scala> def f = { class C(protected implicit val s: String, i: Int) () }
f: Unit

scala> def f = { class C(implicit s: String)
     | () }
<console>:2: error: traits or objects may not have parameters
       () }
       ^

but now

scala> def f = { class C(implicit s: String)
     | new C()("c") }
f: AnyRef

scala> def f = { class C(implicit s: String)
     | () }
ReplGlobal.abort: unexpected opening parenthesis

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@som-snytt said:
scala/scala#5585