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Re: Empty Names

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Mon, 25 Sep 2006 17:25:29 GMT
Message-ID: <diURg.38901$9u.333796@ursa-nb00s0.nbnet.nb.ca>


Marshall wrote:

> Bob Badour wrote:
>

>>Marshall wrote:
>>
>>>Bob Badour wrote:
>>>
>>>>If an attribute has no name, how are we to refer to it?
>>>
>>>Do you know the term a "small matter of engineering?" Well,
>>>this is a "small matter of syntax." :-)
>>>
>>>I can think of a few approaches.
>>>
>>>The first and most comprehensive would be a quoting
>>>mechanism for identifiers, such as Haskell uses. This would
>>>allow one to, for example, have identifier names with spaces,
>>>or empty identifiers, or other otherwise-hard-to-parse
>>>identifiers. This would also insulate one from differences
>>>in legal identifiers as one crossed language boundaries.
>>
>>A name is a name. I don't see how what I said precludes using
>>spaces in names.

>
> I didn't think it did. However spaces in names are another thing that,
> like empty names, are typically hard to parse. I can see some
> modest value to allowing names to be arbitrary strings; this is
> possible with an identifier quoting facility.

Um, so you weren't responding to anything I said but were introducing a whole new topic unrelated to how to refer to something with no name.

Might I suggest that explicit identification of tangents and diversions helps with communication? Nothing fancy, just a few words. "On a related topic..." or "On a separate note..." etc.

>>>Another approach would be the use of syntactic rules
>>>that would allow one to simply omit the name. For
>>>example, if name declaration was always of the
>>>form "name:type" then the colon could be used as
>>>the definitive indication of a declaration, and the name
>>>could simply be optional.
>>
>>But that doesn't solve the problem of how to refer to the thing with no
>>name.

>
> Agreed; this only addresses declaring them. My point 1 however,
> which I said was the "most comprehensive" addresses all
> usages of empty identifiers. Points 2 and 3 show how, in
> limited situations, it might be simpler still.

But a name comprising a zero-length string is still a name--albeit, a name with some usability challenges. How do we refer to an attribute that doesn't have one of those?

>>>Still another shortcut would be the ability to omit the
>>>name when referring to relations with an unnamed
>>>attribute:
>>>
>>>update Table 5 where id = 11; -- sets the unnamed attribute
>>
>>Sets what unnamed attribute to what value?

>
> *The* unnamed attribute. As Connor MacLeod says, "there
> can be only one." And in the above example, the value is
> 5. The above is a shorthand for the longer:
>
> update Table set ``=5 where id = 11;

Are you sure you want to set it to five? What if you want to increase it by five? Is `` not a name? How do we refer to an attribute that doesn't have one of those?

>>If we can have one unnamed
>>attribute, why not two?

>
> Well, is there a useful distinction between not having a name,
> and having an empty name? I suspect not.

Logical differences are big differences. Even if one has a difficult to use name, one has a name.

  In that case, the
> empty string is just another string that can be used as an
> identifier; it doesn't given one a pass to ignore the usual
> rules such as names being required to be unique.

Sure, a zero-length string can be a name and only one attribute can have that name. But how do we refer to an attribute that doesn't have one of those?

> If there is a useful distinction to be made between the
> empty name and no name, I don't know what it would be,
> but it is likely that much of what I'm saying wouldn't apply.

Is there a difference between an object that has a location in our universe and one that doesn't? Does a difference exist between something that's difficult to use and something that's absurd on its face? Is there a difference between "What is a name?" and "What's in a name?" ?

>>>Just some ideas. Whether these are good ideas or
>>>not depends on the entirety of the laguage design.
>>
>>I think you missed my point entirely.

>
> It's entirely possible! And it's possible that I'm talking about
> something completely different than what you et al are
> discussing.

Okay. I thought "If an attribute has no name, how are we to refer to it?" clearly identified what I was talking about. I guess I was wrong. Received on Mon Sep 25 2006 - 12:25:29 CDT

Original text of this message

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