Re: Object-relational impedence

On Mar 6, 6:26 am, Robert Martin <uncle..._at_objectmentor.com> wrote:
> On 2008-03-05 06:48:31 -0600, JOG <j..._at_cs.nott.ac.uk> said:
>
> >>> 1) So why not treat all 'inheritance' in this way?
>
> >> Because all inheritance is not about inference.
>
> > Hmmm. Then might you give an example of a situation where inheritance
> > cannot be described in terms of inference?
>
> Inheritance is simply the redeclaration of functions and variables in a
> subscope.

Using nonsense words like 'subscope' doesn't do conversation any favours Robert. Either way, lets consider the two concepts you mention. First "variable" inheritance:

A person has a name (string)
A man is a person
|= A man has a name (string)

Okay, thats seems straightforward. So now functions:

A lock_view has an update()
A digital_clock_view is a clock_view
|= a digital_clock_view has an update()

Great, that makes sense too. In fact more than that, it seems entirely straightforward.

> That's not inferrence.

Well that all jolly-well looks like inference to me. I must have missed something.<scratches_head/> I don't know, maybe you've gotten so involved with OO that you can't see the wood from the trees in terms of abstracting away from the mechanism?

>
> --
> Robert C. Martin (Uncle Bob) | email: uncle..._at_objectmentor.com
> Object Mentor Inc. | blog: www.butunclebob.com
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Received on Thu Mar 06 2008 - 13:37:19 CET