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Last gasp terminology issue

From: Jeffrey Mogul <mogul@pa.dec.com>
Date: Mon, 03 Jun 96 15:44:37 MDT
Message-Id: <9606032244.AA05396@acetes.pa.dec.com>
To: jg@w3.org
Cc: http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com, koen@win.tue.nl
Koen writes:
    These sections talk a lot about the `requested variant'.  I have
    two problems with this:

    a) it seems to imply that these headers are not useful for
    non-varying resources

Jim writes:
    The semantics are well defined as is; it makes perfect sense as
    definined, I think.  There has been a fundamental disconnect in
    many people's minds about content negotiation; that is that there
    is such a thing as a varying resource, distinct from a non-varying
    one.

    The subtlety is that there is but one thing; a resource.  At any
    given time, there may or may not be more than one entity associated
    with it.

    So saying that something should be used on varying or non-varying
    resources doesn't really make sense, so making such restrictions
    seems wrong to me.

    Maybe I'm missing something here, and would not mind if others
    looked at the definitions yet again.

I think the primary confusion here is the counter-intuitive use
of the term "variant."  Jim tries to explain the philosophy behind
his and Larry's desire to blur the distinction between varying
and non-varying resources.  This, by itself, is not a real problem
for me.

But I suspect that this is a fine distinction that will be missed
by most of the readers of this document, and the use of the word
"variant" to mean "the thing that is copied into the entity carried
in a response" is almost certain to confuse people who have not
grasped the distinction.  The term is used exactly 9 times in rev81
(aside from where it is defined), and only about half of those
uses really discuss varying resources.

So I'll make one last attempt to suggest that the term "variant"
is the wrong one.  I'd still support Koen's suggestion of "entity
source" as the best compromise (given the extremely misleading but
historically accepted misuse of the term "entity").  Among other
things, it fits nicely as a directly replacement for the text
of the definition of "variant".  I.e., this

    variant
      Each representation of that resource that corresponds to a different
      sequence of entities that could be returned for a requested resource
      is termed a variant.

would become

    entity source
      Each representation of that resource that corresponds to a different
      sequence of entities that could be returned for a requested resource
      is termed an entity source.

I would then use the term "variant" to describe an entity source
whose identity is currently subject to content negotiation.

-Jeff
Received on Monday, 3 June 1996 15:52:48 EDT

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