Immutable Utility Objects
Steve Wart <[email protected]> Thu, 1 Dec 2011 11:43:55 -0800
| Newsgroups | gmane.comp.programming.language-of-the-year |
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| Message-ID | <CACvgEZFE5mJm_7X1Qyavb_KbxG1Gxga9EfT3FFQ-yDw9UqvoxA@mail.gmail.com> |
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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 that
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-specific
examples of this.
Alternatively, could it be that creating instances to execute all behavior
overcomes problems with static semantics?
Just curious.
Thanks,
Steve
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<p>Why do some people feel so strongly that implementing class-side behavior is bad design?<br><br>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.<br>
<br>I've heard arguments that this approach "inhibits testing" - 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, there's nothing stopping me from refactoring.<br>
<br>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-specific examples of this.<br>
<br>Alternatively, could it be that creating instances to execute all behavior overcomes problems with static semantics?<br><br>Just curious.<br><br>Thanks,<br>Steve<br>
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