recursive lambda as a local variable

[Remi Forax]

On 09/13/2013 10:21 AM, Peter Levart wrote:
> On 09/12/2013 05:17 PM, Brian Goetz wrote:
>>> - The part left of the '::' can be an arbitrarily long expression that will
>>> be evaluated immediately, while the method invocation itself will be
>>> deferred until the corresponding SAM method is invoked. Thus, 'null' might
>>> by bound now and detected much later.
>> This is just a compiler bug; if the part to the left evaluates to null,
>> it should throw NPE immediately (see jsr335-15.28.2-30-A2: If the result
>> of evaluation of the subexpression is null, then a NullPointerException
>> is thrown.)
>>
>> Thanks for reporting this.  I will file a bug.
> This could be checked in lambda metafactory generated constructor,
> right? It doesn't have to be compiler generated code.
>
> Regards, Peter

yes,
but it requires to change the protocol between javac and the lambda 
metafactory
to signal if a captured parameter is bound or not.

It seems simpler, to me, to modify javac to generate
   DUP
   INVOKEVIRTUAL Object.getClass()
in front of the first argument of the invokedynamic call.

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