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Re: Extension for Boolean attributes

From: Arjun Ray <aray@q2.net>
Date: Fri, 8 Oct 1999 03:32:45 -0400 (EDT)
To: www-html@w3.org
Message-ID: <Pine.LNX.3.95.991008032442.29982T-100000@mail.q2.net>

On Fri, 8 Oct 1999, I wrote:

> Putting these two together, if you define a singleton name token group
> and then name the attribute identically, you can get the "boolean"
> effect of an isolated token not always appearing in a start-tag.

Aargh!  Sorry about that.  This second piece (identical name for the
attribute) is *not* necessary, because it gets left out by minimization.
The name could be anything.

> [Well, that's the theory.  The real story is that HTML's "booleans",
> like SELECTED, ISMAP, and so on, got invented and used first.  A DTD to
> formalize such usage came much later, at which point it became necessary
> to invent names for the attributes identical to these values that people
> were using in a "boolean" manner.  Isn't retro-fitting fun?;)]

So, the real reason for an identical name declared in the spec is to
"support" the behavior of heuristic parsers that treat an isolated token
like "ISMAP" or "SELECTED" as the *name* of an attribute (rather than its
value - this mistake would also explain why they don't grok <H1 center>.)

Received on Friday, 8 October 1999 02:49:26 UTC

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