On Fri, 1 Mar 2019 at 02:46, Stuart Marks <stuart.ma...@oracle.com> wrote: > Please review and comment on this proposal to allow Stream instances to be > used > in enhanced-for ("for-each") loops.
This all seems reasonable enough though of course not ideal. My slight concern is that the terminal operation is hidden and not immediately visible, which could be surprising. I do note that streams throw a clear exception if a terminal operation is called a second time which mitigates this to some degree. The IterableOnce class-level Javadoc contradicts the method-level Javadoc. The class-level say "It is recommended that" whereas the method-level Javadoc mandates. Stephen > Abstract > > Occasionally it's useful to iterate a Stream using a conventional loop. > However, > the Stream interface doesn't implement Iterable, and therefore streams cannot > be > used with the enhanced-for statement. This is a proposal to remedy that > situation by introducing a new interface IterableOnce that is a subtype of > Iterable, and then retrofitting the Stream interface to implement it. Other > JDK > classes will also be retrofitted to implement IterableOnce. > > Full Proposal: > > http://cr.openjdk.java.net/~smarks/reviews/8148917/IterableOnce0.html > > Bug report: > > https://bugs.openjdk.java.net/browse/JDK-8148917 > > Webrev: > > http://cr.openjdk.java.net/~smarks/reviews/8148917/webrev.0/ > > Note, this changeset isn't ready to push yet. In particular, it has no tests > yet. However, the implementation is so simple that I figured I should include > it. Comments on the specification wording are also welcome. > > Thanks, > > s'marks