return-from-lambda viewed as dangerous, good alternatives

[Alex Blewitt]

On Jan 7, 2010, at 21:18, Mike Swingler wrote:

> On Jan 7, 2010, at 12:45 PM, Stephen Colebourne wrote:
>
>> The whole purpose of John's argument is to leave return free to be
>> used in a later JDK for non-local transfer. Lets say that is JDK 8 or
>> 9.But given the glacial speed at which many shops upgrade JDK
>> versions, this will mean that many developers will face jumping
>> straight from JDK 6 to this new JDK 8/9 with non-locals. The same
>> problems that Josh described in Devoxx thus re-appear.
>>
>> Thus I have some rules I'm following here:
>> 1) Developers must be able to trust the 'return' keyword. It must
>> never throw a NonLocalTransfer, now or in the future.
>>
>> 2) Some other element is allowed to do non-local return and throw a
>> NonLocalTransferError, eg 'throw return'.
>>
>> 3) If it looks like a method, ie. round-bracketed arguments followed
>> by code, then it must be a local return.
>
> +1
>
> In all the mainstream languages that have adopted closures, "return"  
> really means the least surprising thing. I think non-local transfers  
> should have a unique keyword or label syntax or whatever, and should  
> work across traditional methods and closures when their time comes.

+1 from me as well.