RE: The non-polyglot elephant in the room

> It's not clear to me that they have that relation. There does exist a
> subset of HTML that is also XHTML and vice versa.

I think using "is" here leads to problems, because you are thinking of HTML and XHTML as sets and trying to characterize the relationship as subset.

But consider "application/octet-stream" and "text/plain".

Evey sequence of bytes "is" application/octet-stream, in the sense that it could legitimately, legally, conformingly delivered as application/octet-stream.

Every sequence of characters "is" text/plain, in the sense that it can be interpreted as splain text.

Yet we don't describe the relationship of XML and XHTML and HTML to each other in the same terms as we describe their relationships to application/octet-stream and text/plain.

The "format" of data is not an intrinsic property. Yes, there are heuristics (sniffing) that you can use to infer probable intent if you have no (or insufficient) information. But sniffing is just guesswork.

Try saying it by being explicit about intent:

There is a subset of content which behaves as expected when interpreted as HTML which will also behave similarly when interpreted as HTML. And vice versa. 

Larry
--
http://larry.masinter.net

Received on Monday, 21 January 2013 22:46:45 UTC