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Re: generics puzzle

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In article <9g81fmFj6eU2@mid.individual.net>,
blmblm@myrealbox.com  <blmblm.myrealbox@gmail.com> wrote:
> In article <9g5salFh1jU2@mid.individual.net>,
> blmblm@myrealbox.com  <blmblm.myrealbox@gmail.com> wrote:
> > In article <9g5nnhFahuU1@mid.individual.net>,
> > Robert Klemme  <shortcutter@googlemail.com> wrote:
> > > On 10/18/2011 04:49 PM, blmblm@myrealbox.com wrote:
> > > > In article<45bfae98-a142-469b-9b8b-9aa8a59391f1@n13g2000vbv.googlegroups.com>,
> > > > Robert Klemme<shortcutter@googlemail.com>  wrote:
> > > >> On Oct 17, 12:41 pm, blm...@myrealbox.com<blmblm.myreal...@gmail.com>
> > > >> wrote:
> 
> [ snip ]
> 
> > > >> In your case since apparently you want to update internally why not
> > > >> just introduce
> > > >>
> > > >> public void update() {
> > > >>    set(modified());
> > > >> }
> > > >
> > > > I'm not sure I can say why this doesn't appeal to me -- something
> > > > about not wanting to clutter up GThing with unnecessary methods.
> > > 
> > > Why is it unnecessary?  It seems this provides a proper abstraction.  As 
> > > your example shows and concluding from what you write below you do 
> > > already have two or more uses for it.  So by having the method you can 
> > > actually reduce redundancy.  That's a common pattern: we find we do 
> > > something over and over again, we turn it into a method or procedure.
> > 
> > Yeah, maybe.  I'll look some more at my actual code.
> > 
> > > >> This will safely compile.  Basically this is what you did with
> > > >> setModified() in the wrapper class.  All other approaches will be
> > > >> hacky (i.e. involve explicit casting, using Object parameters or
> > > >> return values etc.).
> > > >
> > > > Yeah, maybe ....  In my "real" code (quotation marks because it's
> > > > a toy project embarked on for entertainment and a bit of education)
> > > > the method in the wrapper class does more than just call modified()
> > > > and then set().  I don't know that that matters much, though.  
> 
> What may matter, though, is that sometimes I want to immediately
> pass the value returned by modified() to set(), while other times
> I want to save the value returned by modified() locally, from where
> it might or might not later be passed to set().
> 
> My most recent refactoring of the "real" code uses static generic
> methods (as suggested somewhere upthread), and for now that seems
> not-bad.  I'll probably change my mind again at some point.  :-)?
> 

And I did, so -- a very belated follow-up, for the record maybe ....

Eventually, after much rearranging of the furniture, I came
around to the idea that maybe it did make more sense to put the
desired functionality in GThing.  In my "real" application I
wanted to be able to compute a possibly-temporary result and then
later optionally save it.  What I ended up doing was storing the
possibly-temporary value in the GThing (rather than returning it
for the caller to keep track of) and adding a method to GThing to
save the possibly-temporary value.  There are still some things
about this setup and how it fits into the overall application
that feel like ugly hacks, but the application does what I wanted
it to do, and at some point one has to say "good enough for now"
and move on, maybe.

-- 
B. L. Massingill
ObDisclaimer:  I don't speak for my employers; they return the favor.

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generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-17 10:41 +0000
  Re: generics puzzle Steven Simpson <ss@domain.invalid> - 2011-10-17 13:14 +0100
    Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-17 15:14 +0100
    Re: generics puzzle markspace <-@.> - 2011-10-17 07:33 -0700
      Re: generics puzzle Steven Simpson <ss@domain.invalid> - 2011-10-17 16:26 +0100
        Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-18 14:48 +0000
      Re: generics puzzle Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-10-17 15:36 +0000
    Re: generics puzzle Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-10-17 08:58 -0700
      Re: generics puzzle Steven Simpson <ss@domain.invalid> - 2011-10-18 10:45 +0100
        Re: generics puzzle Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-10-18 09:42 -0700
          Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-19 13:25 +0000
            Re: generics puzzle Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-10-19 10:04 -0700
              Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-20 14:14 +0000
                Re: generics puzzle Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-10-20 11:11 -0700
  Re: generics puzzle Robert Klemme <shortcutter@googlemail.com> - 2011-10-17 09:12 -0700
    Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-18 14:49 +0000
      Re: generics puzzle Robert Klemme <shortcutter@googlemail.com> - 2011-10-18 18:27 +0200
        Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-18 17:45 +0000
          Re: generics puzzle Robert Klemme <shortcutter@googlemail.com> - 2011-10-18 22:15 +0200
          Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-18 18:59 -0700
            Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-19 13:28 +0000
              Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-20 17:21 -0700
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-21 16:27 +0000
                Re: generics puzzle Robert Klemme <shortcutter@googlemail.com> - 2011-10-21 20:34 +0200
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-22 18:50 +0000
                Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-22 21:02 +0100
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-25 07:04 +0000
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-25 23:25 -0700
                Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-26 21:56 +0100
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-27 08:59 +0000
                eclipse shortcuts again (was Re: generics puzzle) blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-29 17:05 +0000
                Re: eclipse shortcuts again (was Re: generics puzzle) Four of Seventeen <fseventeen@gmail.com> - 2011-10-29 19:49 -0700
                Re: eclipse shortcuts again (was Re: generics puzzle) blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-31 11:17 +0000
                Re: eclipse shortcuts again (was Re: generics puzzle) Four of Seventeen <fseventeen@gmail.com> - 2011-10-31 05:39 -0700
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-23 01:30 -0700
                Re: generics puzzle Lew <lewbloch@gmail.com> - 2011-10-23 08:56 -0700
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-24 02:46 -0700
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-25 07:05 +0000
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-25 23:29 -0700
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-31 11:14 +0000
                Re: generics puzzle Four of Seventeen <fseventeen@gmail.com> - 2011-10-31 05:34 -0700
          Re: generics puzzle markspace <-@.> - 2011-10-18 21:21 -0700
            Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-19 13:29 +0000
              Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-20 17:22 -0700
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-21 16:28 +0000
              Re: generics puzzle Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2011-10-21 06:22 -0300
                Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-21 16:29 +0000
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-23 01:20 -0700
                Re: generics puzzle Martin Gregorie <martin@address-in-sig.invalid> - 2011-10-23 09:51 +0000
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-23 03:28 -0700
                Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-23 15:59 +0100
                Re: generics puzzle Eight of Seventeen <eights17@gmail.com> - 2011-10-24 02:46 -0700
                Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-23 15:55 +0100
            Re: generics puzzle Tom Anderson <twic@urchin.earth.li> - 2011-10-20 21:00 +0100
          Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-19 13:26 +0000
            Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-11-25 17:46 +0000
          Re: generics puzzle Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2011-10-21 05:57 -0300
            Re: generics puzzle blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-10-21 16:28 +0000

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