Re: Future of meta-indices: site indexing proposal and Perl script

Dave Raggett (
Wed, 23 Mar 1994 10:37:47 --100

Kevin Altis writes:

> you should be able to extract particular sections or pages of
> any document. So, you could retrieve page 3-4 of a PostScript
> document, paragraph three on page 4 of a Word document, a rectangle
> from 10,15 to 108,112 of a GIF image, etc.

and John C. Mallery writes:

> It would be nice if the document fragment could be specified
> stuff between two arbitrary points in a document, rather than
> relying exclusively on everything to be named.

Some of the HyTime concepts may be useful here. HyTime extends
SGML's reference capability to accommodate those cases in which
no unique identifier exists in the document's name space. Authors
can create a location address element that pairs the object in
question with a unique local identifier. There are three kinds
of addressing:

a) by name (using ID attributes)
b) by position in a coordinate space (the GIF example)
c) by semantic construct (e.g. the 3rd polygon on the left)

A summary of these capabilities can be found in the November '91
issue of Communications of the ACM (Volume 34, number 11).

Best wishes,

Dave Raggett

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