Re: Objects and Relations

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Wed, 21 Feb 2007 15:09:20 GMT
Message-ID: <AgZCh.9048$R71.139804_at_ursa-nb00s0.nbnet.nb.ca>

Walt wrote:

> "David BL" <davidbl_at_iinet.net.au> wrote in message
> news:1172023595.106358.33710_at_q2g2000cwa.googlegroups.com...
>

>>On Feb 21, 12:03 am, "Walt" <wami..._at_verizon.net> wrote:
>>
>>>In casual conversation,  ER modelers will tend to use the simple word
>>>"entity" in place of either "entity set" or "entity instance", leaving

>
> the
>

>>>listener to disambiguate by means of the context in whuch the word

>
> appears.
>

>>>By analogy, in casual conversation, object oriented programmers will use

>
> the
>

>>>simple word "object" in place of either "object class" or "object

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> instance",
>

>>>similarly leaving disambiguation up to the listener.
>>>
>>>The problem comes when the listener is not familiar with the underlying

>
> mode
>

>>>of thinking.  In that case, the listener will sometimes disambiguate
>>>incorrectly.  That is why introductory tutorials on object oriented
>>>programming tend to spell out "object class" or "object instance",  at

>
> least
>

>>>until the reader can be presumed to have gotten accustomed to the mode

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> of
>

>>>thinking.  I'm sure you will have noticed this, if you've gone back and

>
> read
>

>>>some introductory material after gaining proficiency.
>>>
>>>Similarly,  introductory material on ER modeling should spell out when

>
> we
>

>>>are talking about the "set of all vehicles" and when we are talking

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> about "a
>

>>>particular vehicle".  Some such material does this.
>>>
>>>Discourse in this newgroup tends to be a little more formal than casual
>>>conversation,  but far less formal than introductory tutorials.
>>>
>>>Hope this helps.
>>
>>I prefer to only use "object" to mean instance.   Why would one say
>>object when one means class?  ie given that we have different words
>>for these different concepts, let's use them!

If "object" means object instances exclusively, then the term is synonymous with "variable". Why would one say "object" when one means "variable" ? Received on Wed Feb 21 2007 - 16:09:20 CET