Concat operation

[David M. Lloyd]

I think it might be more correct to simply return the infinite stream 
and clear/discard the additional stream.  I could see cases where you 
don't need or want to know whether the target is infinite or not, but 
you want to add a certain group to the end if there *is* an end (but if 
there isn't, it wouldn't matter).

On 09/18/2012 09:15 AM, Paul Benedict wrote:
> Shouldn't it be illegal to concat on an infinite stream? I propose throwing
> ISE if the target stream is infinite.
>
> On Tue, Sep 18, 2012 at 7:12 AM, Paul Sandoz <paul.sandoz at oracle.com> wrote:
>
>> Hi,
>>
>> Please see here for a first go at implementing concat:
>>
>>    http://cr.openjdk.java.net/~psandoz/lambda/concat/webrev/
>>
>> I chose to implement:
>>
>>    stream.concat(anotherStream)
>>
>> so that the elements of "anotherStream" are concatenated on to end of
>> "stream".
>>
>> This operation has side-effects.
>>
>> I am not sure how this operation relates to MapStream.mergeWith.
>>
>> I pulled out the concatenating of Iterator<Iterator<T>> from TreeUtils,
>> spruced (no pun intended) it up, and placed it in Iterators for reuse.
>>
>> There is only the dumb parallel implementation. One wonders for the
>> parallel case whether concat should be pseudo-random interleave :-)
>>
>> I updated the StreamOpTestCase exercise methods to take a
>> Factory<IntermediateOp[]> since concat has side-effects:
>>
>>          exerciseFOp(data, () -> ConcatOp.make(data.seqStream()));
>>
>> (Another TODO for these test methods is to select which cases to test).
>>
>> Paul.
>>
>>
>


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