Re: Immutable Utility Objects

Chris Morris <[email protected]> Sun, 4 Dec 2011 10:31:06 -0600
Newsgroups	gmane.comp.programming.language-of-the-year
Message-ID	<CA+HVNMd5RfWDf0Y9GUZzZz=foAjXmVdN5cgkFRkWpWYo_Ek+zg@mail.gmail.com>
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I think my objections stem from abuse I've seen in codebases**. In your
case, it sounds like you're being reasonable about it. I'm okay with it as
long as that code is properly groomed and refactored as it grows, and
usually that means away from class level into instance level - so sometimes
I'll just start there rather than worry about a team making the transition
when the time comes.

** (a) a set of static methods that all take the same or similar arguments
and pass them among each other or (b) utility classes or packages that
become a kitchen sink of functionality that become a hub to couple
everything to everything else.

On Thu, Dec 1, 2011 at 1:43 PM, Steve Wart <[email protected]> wrote:

> **
>
>
> Why do some people feel so strongly that implementing class-side behavior
> is bad design?
>
> For example, I've got an object with no mutable state, and no required
> inheritance, just a set of related utility functions that are needed to
> fire off some processing.
>
> I've heard arguments that this approach "inhibits testing" - but does tha=
t
> trump the KISS principle? I seem to be able to test just fine.
>
> After all if I need a singleton, or even multiple instances, there's
> nothing stopping me from refactoring.
>
> Could it be I'm mistaken in the assumption that people think it's bad?
> After all most languages these days have a "Math" import that has nothing
> but static behavior, and I'm sure there are many other application-specif=
ic
> examples of this.
>
> Alternatively, could it be that creating instances to execute all behavio=
r
> overcomes problems with static semantics?
>
> Just curious.
>
> Thanks,
> Steve
>=20=20
>



--=20
Chris
http://livingsocial.com | http://clabs.org

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      <p><div>I think my objections stem from abuse I&#39;ve seen in codeba=
ses**. In your case, it sounds like you&#39;re being reasonable about it. I=
&#39;m okay with it as long as that code is properly groomed and refactored=
 as it grows, and usually that means away from class level into instance le=
vel - so sometimes I&#39;ll just start there rather than worry about a team=
 making the transition when the time comes.</div>
<div><br></div><div>** (a) a set of static methods that all take the same o=
r similar arguments and pass them among each other or (b) utility classes o=
r packages that become a kitchen sink of functionality that become a hub to=
 couple everything to everything else.</div>
<div><br><div class=3D"gmail_quote">On Thu, Dec 1, 2011 at 1:43 PM, Steve W=
art <span dir=3D"ltr">&lt;<a href=3D"mailto:[email protected]" target=3D=
"_blank">[email protected]</a>&gt;</span> wrote:<br><blockquote class=3D=
"gmail_quote" style=3D"border-left:1px #ccc solid;">




<u></u>










<div style=3D"background-color:#fff;">
<span>=A0</span>


<div>
  <div>


    <div>
=20=20=20=20=20=20
=20=20=20=20=20=20
      <p>Why do some people feel so strongly that implementing class-side b=
ehavior is bad design?<br><br>For example, I&#39;ve got an object with no m=
utable state, and no required inheritance, just a set of related utility fu=
nctions that are needed to fire off some processing.<br>


<br>I&#39;ve heard arguments that this approach &quot;inhibits testing&quot=
; - but does that trump the KISS principle? I seem to be able to test just =
fine.<br><br>After all if I need a singleton, or even multiple instances, t=
here&#39;s nothing stopping me from refactoring.<br>


<br>Could it be I&#39;m mistaken in the assumption that people think it&#39=
;s bad? After all most languages these days have a &quot;Math&quot; import =
that has nothing but static behavior, and I&#39;m sure there are many other=
 application-specific examples of this.<br>


<br>Alternatively, could it be that creating instances to execute all behav=
ior overcomes problems with static semantics?<br><br>Just curious.<br><br>T=
hanks,<br>Steve<br>
</p>

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=20=20=20=20=20

=20=20=20=20
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=20=20






</div></div></blockquote></div><br><br clear=3D"all"><div><br></div>-- <br>=
Chris<div><a href=3D"http://livingsocial.com" target=3D"_blank">http://livi=
ngsocial.com</a> |=A0<a href=3D"http://clabs.org" target=3D"_blank">http://=
clabs.org</a><br></div>

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