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Re: generics puzzle

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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:

> Nice job of putting into words my vague idea about what's wrong;
> thanks!

Thank _you_.

>> 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.

>> 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.  I do
> have a couple of different "call sites" (to use another poster's term)
> that need similar functionality, so maybe it *does* go in GThing.
> Well, like I said, "entertainment and a bit of education", and for
> me that seems to involve -- the coding equivalent of periodically
> rearranging the furniture, maybe.

That's called "refactoring" - and is quite frequent with "real" code in 
my experience. :-)  Certainly not something to be afraid of - with 
proper tools it can even be fun. :-)

I think you're on the right track: best learning experience is by having 
a toy project and trying out different things.  That way you see what 
works and what not - and you get the satisfaction of having found out 
yourself.

Kind regards

	robert

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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 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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