return-from-lambda viewed as dangerous, good alternatives

[Stefan Schulz]

On 09.01.2010 01:20, Neal Gafter wrote:
> On Fri, Jan 8, 2010 at 3:54 PM, Alex Buckley<Alex.Buckley at sun.com>  wrote:
>> Neal Gafter wrote:
>>>
>>> The point of intersection is checking that Sun's Project Lambda does
>>> not preclude transparency.  That discussion is appropriate here, no?
>>
>> John Rose's outstanding initial mail did that. It and the immediate
>> follow-ups gave others of us at Sun a lot to think about. I'm not sure it's
>> necessary to rehash restricted v. unrestricted BGGA semantics, which is what
>> separating "blocks" from "closures" effectively did up-thread.
>
> My question is about further evaluation of Project Lambda as it
> evolves with respect to whether or not and how it might preclude
> transparency.  I would expect that to be appropriate here, as such
> discussion elsewhere is unlikely to have the required impact.

I'd suspect that in the sense of this proposal, a lambda is (like in, 
e.g., Ruby) what FCM defined as "anonymous inner method", which also 
clarifies its behaviour wrt. non-local return. It does not prevent, 
however, from adding another language construct for control abstraction 
or closures (Blocks in Smalltalk) later on with a syntax distinct from 
methods (e.g. old BGGA syntax). As I mentioned Ruby, it provides 
different constructs for lambda and closure (proc).

Cheers
Stefan