closures after all?

[Joshua Bloch]

Neal,

I'm not sure why you consider this to be simpler than the current,
interface-based approach to ARM blocks.  To be honest, it strikes me as a
bit convoluted. I'm not saying that I don't believe extension methods to be
a good thing, but I'm not convinced that they change the preferred approach
to ARM blocks.

     Josh

On Thu, Nov 19, 2009 at 3:58 PM, Neal Gafter <neal at gafter.com> wrote:

> I also heard a rumor about extension methods.  If so, that would suggest a
> much simpler approach to ARM blocks.  From
> http://www.javac.info/ExtensionMethods.html:
>
> One of the biggest advantages of extension methods is that they enable more
> flexible extension of the language moving forward. For example, suppose a
> new Automated Resource Management statement were defined in terms of
> invoking an acquire() method, and then later invoking a release() method on
> the result of the earlier acquire(). Clearly existing APIs such as
> Closeable
> do not implement this protocol, but by providing static factory methods
> they
> could be made to act as if they do. Such a statement could then be easily
> retrofitted onto other resource APIs, such as
> java.util.concurrent.locks.Lock (an interface), simply by providing
> extension methods. This retrofitting introduces no breaking changes, since
> the underlying APIs are not changed.
>
> -Neal
>
> On Thu, Nov 19, 2009 at 12:46 AM, Mark Mahieu <markmahieu at googlemail.com
> >wrote:
>
> > *sigh*
> >
> > I suppose I should have guessed that a deliberately silly bit of code
> like
> > this would get linked to or reproduced in edited form elsewhere (without
> my
> > 'tongue-in-cheek' disclaimer).
> >
> > So, for the bloody record:
> >
> > 1) I have absolutely no idea whether it will ever be considered valid
> Java.
> > 2) Even if it will be valid, I don't think it's remotely representative
> of
> > code which will use ARM, or closures, or both.
> > 3) Even if it will be valid, and someone decides to write something like
> > this, I don't think it will be hard to understand what it does.
> > 4) 'YOUR HEAD A SPLODE' refers to the mixing of ARM and closures, which
> > some on this list may find mildly ironic.  It was not intended as serious
> > commentary on the potential uses of those features, individually or in
> > tandem.  If I have serious concerns to raise at some point, I probably
> won't
> > choose to back them up by quoting an animated mexican wrestler.
> >
> > On the other hand, I was serious about it being interesting to
> investigate
> > the interaction between the various language features.
> >
> > Sincere apologies for any confusion (!)
> >
> > Mark
> >
> >
> > On 18 Nov 2009, at 23:49, Mark Mahieu wrote:
> >
> > > Well it'll be interesting to see the official details, and (to bring it
> > back on topic) see how it interacts with Coin's language enhancements.
> > >
> > > // tongue in cheek
> > > try (Closeable closure = #() { System.out.println("YOUR HEAD A
> SPLODE");
> > }) {
> > >       // ...
> > > }
> > >
> > >
> > > Mark
> >
> >
> >
>
>