Proposal: Collection Literals (original) (raw)

Joshua Bloch jjb at google.com
Mon Mar 30 19:29:57 PDT 2009

Neal, Sorry, I'm still confused. Can you tell me what client code would cause trouble, or at least give me a few examples?

   Thanks,

   Josh

On Mon, Mar 30, 2009 at 5:58 PM, Neal Gafter <neal at gafter.com> wrote:

On Mon, Mar 30, 2009 at 5:45 PM, Joshua Bloch <jjb at google.com> wrote: > Could you please be a be a bit more specific? In particular, could you > provide an example of something that this proposal precludes but the > for-each construct (which is already in the language) does not? Once we > have such an example, we'll be able to weigh the pros and cons > intelligently.

Sure. As the proposed construct is defined to create non-reified collection types, and that distinction may be highly visible to programmers, programs using the proposed syntax would have to continue creating non-reified collections. With the for-each loop, on the other hand, the only object created by the construct is an iterator. The iterator is constructed by a library method that is completely under control of the Iterable that comes in, and hidden from code containing the for-each loop. While non-reified types might continue to produce non-reified iterators, reified classes may well produce reified iterators.

More information about the coin-dev mailing list