Re: Jade for HTML

["W. Eliot Kimber" <eliot@xxxxxxxxxx>]

At 05:39 AM 4/22/97 -0700, G. Ken Holman wrote:

>I'm planning to hardcode <A> elements that are external to the website and
>custom code <intA> elements that are internal to the website ... with the
>engine producing the required <A> element for the output of the "internal"
>reference.  

By "hardcode" do you mean putting URLs directly on the A elements or do you
mean refering to data entities whose system identifiers are URLs?

I haven't tried it yet, but it should be easy enough to implement simple
HyTime indirection with Jade, using either the original nameloc/nmlist
design or the new and improved name-space location address (nmsploc), shown
below.

For example, to have a single hyperlinking element that always uses IDREF
and can directly refer to elements in the same document and indirectly
refer to objects without IDs (including elements in other documents), you
would do something like this:

<!DOCTYPE MyDoc PUBLIC "-//ME//DTD Mine//EN" [
 <!ELEMENT nmsploc  -- Name-space location address, optimized for addressing
                       elements in other documents. --
           - - (#PCDATA) -- Content is list of names --
 >
 <!ATTLIST nmsploc
           ID      ID   #REQUIRED
           locsrc  -- Location source: node in grove that exhibits
                      name space.  If a document or subdocument entity,
                      addresses root of document grove (SGMLDOC). 
                      If not specified, addresses document in which 
                      nmsploc occurs. 
                   --
                   ENTITY #IMPLIED
           namespc -- Name space being addressed.  Can be any named
                      node list property in grove.  Location source
                      directly or indirectly addresses node that 
                      exhibits the property. --
                    (elements|entities) elements
           naimpsrc -- Implied location source (when locsrc not specified
                       or names document or data entity). --
                    (grovert|ptreert) "grovert" -- Grove root --
           HyTime   NAME  #FIXED "nmsploc"
 >
 <!ENTITY % user-locaddrs "nmsploc" >

 <?FSIDR URL > <!-- Declare use of URL formal system identifier notation -->
 <!NOTATION URL SYSTEM -- HTTP URLs -->
 <!NOTATION HTML SYSTEM -- HTML documents: no reason to pretend they're
                           SGML any more. -->
 <!ENTITY drmacro.home SYSTEM "<url>http://www.drmacro.com"; 
                       NDATA HTML >
>
<mydoc>
<location-addresses>
 <nmsploc id=drmhome locsrc=drmacro.home>HYPERLINKS</nmsploc>
</location-addresses>
 ...
<p>For more about HyTime see <a refid=drmhome>Dr. Macro's Home Page</>... 
 ...
</mydoc>

One problem with having linking elements that are distinguished by the form
of address (internal vs. external), is that when you discover that managing
your data as a single instance becomes unworkable (which you will), you
will have the problem that what were internal references become external
references among the members of the compound document that represents your
Web site.  In my opinion, it's better to plan for that from the start and
build the necessary infrastructure to begin with.

If you wanted to be more direct with the URL stuff, you could create a
"URLloc" element type that is derived from the new "queryloc" form:

<!ELEMENT URLloc - - (#PCDATA) -- Content is a URL  --
>
<!ATTLIST URLloc
          ID    ID   #REQUIRED
          notation (URL) URL
          HyTime  NAME  #FIXED "queryloc"
>

Used like so:

<location-addresses>
 <nmsploc id=drmhome locsrc=drmacro.home>HYPERLINKS</nmsploc>
 <!-- Equivalent URLloc: -->
 <urlloc id=drm-richiii>http://www.drmacro.com/rich-iii</urlloc>
</location-addresses>

This would save having to declare the entity for the HTML document.

If you insist on putting the URL directly on an element, HyTime provides a
mechanism for declaring that the URL is a reference that a HyTime-aware
processor should process:

<!ELEMENT Aext -- hyperlink that only links to HTML pages --
          - - (#PCDATA) >
<!ATTLIST Aext
          href  CDATA #REQUIRED -- URL --
          loctype CDATA #FIXED "href QUERYLOC #NOTATION URL"
          HyTime  NAME  #FIXED "clink"
          HyNames CDATA #FIXED "linkend href"
>

Used like so:

<aext href="http://www.drmacro.com/bookrev";>Click here to review my
book on HyTime</aext>

Cheers,

E.