Thanks Gavin. Regards Manoj
-----Gavin Bierman <gavin.bier...@oracle.com> wrote: ----- To: Manoj Palat <manoj.pa...@in.ibm.com> From: Gavin Bierman <gavin.bier...@oracle.com> Date: 05/21/2020 07:10PM Cc: amber-spec-experts@openjdk.java.net Subject: [EXTERNAL] Re: Switch Expression - complete normally - spec omission? Thanks Manoj. I’ve filed this as a bug [1] and we’ll fix it for JDK 15. Cheers, Gavin [1] https://bugs.openjdk.java.net/browse/JDK-8245546 On 16 May 2020, at 10:10, Manoj Palat <manoj.pa...@in.ibm.com> wrote: Thanks Alex for the reply and clarifying that we are discussing Switch Statements with Switch rules. My bad for putting the title as Switch Expressions - don't want to correct the title now which will break the chain of the mail. Regards, Manoj -----"amber-spec-experts" <amber-spec-experts-boun...@openjdk.java.net> wrote: ----- To: amber-spec-experts@openjdk.java.net From: Alex Buckley Sent by: "amber-spec-experts" Date: 05/15/2020 11:34PM Subject: [EXTERNAL] Re: Switch Expression - complete normally - spec omission? On 5/14/2020 7:22 PM, Manoj Palat wrote: I think there is a spec omission regarding "complete normally for switch statements whose switch block consists of switch rules Ref JLS 14 Sec 14.22 ... A switch statement whose switch block consists of switch rules can complete normally iff at least one of the following is true: – One of the switch rules introduces a switch rule expression (which is necessarily a statement expression). – One of the switch rules introduces a switch rule block that can complete normally. – One of the switch rules introduces a switch rule block that contains a reachable break statement which exits the switch statement. ... Now consider: switch (b) { case 1 -> { throw new Exception(); } } As per the above definition, this switch statement cannot complete normally; but consider "b" having a value other than 1 and then it completes normally. /* ----- To demonstrate the point, the switch statement above uses a switch rule block that completes abruptly, but could alternatively have used a switch rule `throw` statement: switch (b) { case 1 -> throw new Exception(); } Also, to clarify for the many readers of this list, we are discussing switch statements, which never require a `default` label. We are not discussing switch expressions, which almost always require a `default` label. ----- */ Also consider, 14.11.3. which says: "If no switch label matches, the entire switch statement completes normally." which looks inconsistent. One hand says: "completes normally" the other: "iff at least one of the following ..." not mentioning default. Hence, shouldn't the item, -> – The switch block does not contain a default label. also be added in the list in 14.22? I agree that without a `default` switch label, 14.11.3 may evaluate "If no switch label matches, the entire switch statement completes normally." Since we can see a way for the statement to complete normally, 14.22 ought to say that the statement _can_ complete normally. So, it looks right to add "– The switch block does not contain a default label." Alex
