Re[2]: [cgmo-webcgm] ISSUE: is apsid an attribute?

[Benoit Bezaire <benoit@itedo.com>]

Dieter makes a good point... From a DOM perspective, why should 'name'
be an attribute but not the APS id?

-- 
 Benoit   mailto:benoit@itedo.com

 
Friday, July 8, 2005, 10:35:45 AM, Dieter wrote:

DW> Lofton,

DW> see below

>> -----Original Message-----
>> From: Lofton Henderson [mailto:lofton@rockynet.com]
>> Sent: Friday, July 08, 2005 4:29 PM
>> To: cgmo-webcgm@lists.oasis-open.org
>> Subject: Re: [cgmo-webcgm] ISSUE: is apsid an attribute?
>>
>>
>> Expressing my own (mild) preference...
>>
>> I guess I'd prefer that apsid is *not* included in the
>> 'attributes' of the
>> WebCGMNode interface of DOM.  Reasons:
>>
>> -- myAps.apsId already gives quick and immediate access to the
>> apsid.  ('apsId' is the attribute on the WebCGMAppStructure interface).
>>
>> -- if we take the interpretation that apsid is *not* one of the
>> attributes,
>> myAps.hasAttributes() would return false unless there are **APS
>> Attributes** (in the metafile sense) in the given target APS.
>> Otherwise it
>> would always return true, and you would have to look at
>> myAps.attributes.count to see if there are any APS Attributes --
>> if we were
>> to take the interpretation that apsid is one of the 'attributes', then
>> count is always at least 1, and you'd have to check for >1 to
>> determine if
>> there are any APS Attributes.
>>
>> I'm having trouble thinking of any *strong* arguments one way or the
>> other.  Does anyone see any strong arguments for having apsid be
>> one of the
>> 'attributes' of the WebCGMNode interface?

DW> Common sense among script writers, I guess.
DW> There is no other case that I am aware of where there is an ID on an
DW> element, and it is not an attribute.
DW> If we treat it as an attribute, everybody will understand easily, and
DW> will be able to work with it without further explanation.
DW> Otherwise (if we don't make it an attribute), we have the following
DW> situation:
DW> In the XCF, apsID is clearly an attribute,however, in the DOM, it is
DW> not an attribute, is is something different. This leads to the situation
DW> that binding between XCF and CGM file happens between an XML attribute
DW> on the one side and a non-attribute on the CGM side.
DW> And then we start explaining that apsID is an attribute, but it is not
DW> really an attribute, it is just a parameter to the Begin APS element...
DW> In addition, "apsName" (sp?) IS an attribute, so there we bind from
DW> an XML attribute to a CGM attribute.
DW> All in all, quite confusing. Hardly understandable if you don't know
DW> CGM inside out.

DW> Cheers,
DW> Dieter


>>
>> Cheers,
>> -Lofton.
>>
>> At 07:20 PM 7/7/2005 -0600, Lofton Henderson wrote:
>> >Source:  editors / test writers.
>> >
>> >ISSUE:  does the apsid parameter of the BegAps element show up as an
>> >attribute in the DOM?
>> >
>> >DESCRIPTION:
>> >
>> >WebCGMNode contains a boolean method, hasAttributes(), and an
>> attribute of
>> >type node-list, 'attributes'.  What qualifies as an attribute is not
>> >defined anywhere.  The obvious thing that comes to mind is APS
>> Attributes
>> >(on APS nodes).  The text says the value of 'attributes' will be null in
>> >the case that the WebCGMNode has no attributes.
>> >
>> >WebCGMAppStructure, which inherits from WebCGMNode, has an additional
>> >attribute, 'apsId'.  In metafiles, the apsid is a parameter on
>> the BegAps
>> >element (along with the 'type' and the 'inheritance flag' parameters).
>> >
>> >The initial code of the test Node-attr.html shows that the apsid
>> is being
>> >treated in the test as if it is an 'attribute'.
>> >
>> >So should DOM return the metafile apsid as an 'attribute' (WebCGMNode
>> >interface), or only as the 'apsId' on the WebCGMAppStructure
>> interface, or
>> >both?
>> >
>> >It seems to me that the way we designed the interfaces and their
>> >methods/attributes seems to hint at "only 'apsId'".  On the other hand,
>> >Benoit seems to remember some past decision for 'attribute' or
>> "both".  If
>> >that is the case, note that hasAttributes() will always return
>> true for an
>> >APS node (by far its most usual usage, if not the only usage), and
>> >'attributes' will always have a count of at least 1.  Also note that in
>> >XCF, apsid is a required XML attribute on all the APS elements (and the
>> >bindById, of course).
>> >
>> >It is not really critical *how* we answer it.  We have some
>> freedom in how
>> >we map the structured metafile instance onto an XML-like DOM
>> tree.  But it
>> >is critical that we have a clear answer and document it.
>> >
>> >ALTERNATIVES:
>> >Alt.1:  'apsId' only
>> >Alt.2:  'attribute' only (which would mean eliminate 'apsId')
>> >Alt.3:  both
>> >
>> >RECOMMENDATION:  none yet, TC should discuss.  Implementors,
>> what have you
>> >done?
>> >
>> >Regards,
>> >-Lofton.