should 'things' have a magic 'ALL' field?

OK, folks, thinking-caps-on time...  This is a question
about adding something to the ARK engine.

I'll use a 'package' example but there's nothing
package-specific, really.  Imagine you have a <package
name="xemacs--21.5"> (a 'thing') with

   <prototype team="op" name="xemacs" />

In <your-site>/package/xemacs--21.5.xml, you have

   <compile>
     <param name="CC"> gcc </param>
     <param name="CFLAGS"> -O3 </param>
   </compile>

and in the proto-package op/package/xemacs.xml, you have

   <compile>
     <param name="CC"> cc </param>
     <param name="CFLAGS"> -g </param>
   </compile>

   <install>
     <param name="CC"> cc </param>
     <param name="CFLAGS"> -g </param>
   </install>

Should you ask the ARK engine, "please look up the field
<compile> for the object xemacs--21.5", the params CC and
CFLAGS will be set from xemacs--21.5, and the param values
in the prototype will be overridden, effectively.

Had you asked for the <install> field instead, you would get
the param values (cc and -g) from the prototype.

This is core ARK behavior.

Notice that all fields (<compile> vs <install>) are
independent of each other.  If both fields need to be fed
the same info (dependencies, for example), you gotta specify
it twice or more.

So: would there be any value to a magic <ALL> field?  I
guess it couldn't have a value  (string,table,list,code),
but it could set <param>s and <constraint>s, and perhaps
other stuff.

In a case like the one above, you would write

    <ALL>
      <param name="CC"> gcc </param>
      <param name="CFLAGS"> -O </param>
    </ALL>

and then you wouldn't (need to) set these <param>s at all in
individual fields (<compile>, <install>, etc.)

The semantics would be: The <ALL> field would be looked up
in the normal way -- following prototype links and all.
Whatever you picked up from the <ALL> field are injected
into the proceedings immediately before the value
(string,table,list,code).  In the typical case, think of it
as coming after the last <param> before you hit the <code>.

A magic <ALL> field would definitely remove some unsightly
duplication.  I worry that it is too ugly for words and a
complication too far... Anyone got a view?

Will