Re: [whatwg] HTML5: compatible with all legacy Web browsers

[Ian Hickson]

On Thu, 6 Aug 2009, Elliotte Rusty Harold wrote:
>
> Section 1.7:
> 
> "The first such concrete syntax is "HTML5". This is the format 
> recommended for most authors. It is compatible with all legacy Web 
> browsers."
> 
> I challenge the claim that HTML5 is compatible with *all* legacy Web 
> browsers. I can produce valid HTML 4 documents today that are not 
> compatible with *all* legacy Web browsers. I suggest this be weakened to 
> something like "is compatible with most Web browsers still in active use 
> today".

Changed "all" to "most".


On Fri, 7 Aug 2009, Simon Pieters wrote:
> 
> I guess the following is an example of a valid HTML5 document that is 
> incompatible with legacy Web browsers:
> 
>
>
>
>Hello world

It's certainly possible to use the language in a way that is incompatible 
with legacy UAs. 


On Fri, 7 Aug 2009, Aryeh Gregor wrote:
>
> I think the meaning of "compatible with all existing browsers" here is
> that HTML 5 does not *require* authors to break compatibility with any
> existing browser.

Exactly.


> Clearer wording might be like, "HTML5 pages can be written to be 
> compatible with all legacy Web browsers."  Of course, "all legacy Web 
> browsers" does need to be construed to exclude Netscape Navigator 3 and 
> such.  If you really want to be picky, it could be "all legacy Web 
> browsers that still see significant use."

I think just saying the language is compatible is probably clear enough.


On Fri, 7 Aug 2009, Erik Vorhes wrote:
> 
> I agree completely with your interpretation of the phrase. HTML5 is 
> intended to enhance the web without breaking it, so noting (or even 
> emphasizing) how it's backwards-compatible is important and useful.
> 
> But the phrase should be clarified along similar lines to what you've 
> articulated. Maybe: "HTML5 can be written in such a way that it is 
> compatible with all browsers made after X date"?

I don't think most people reading this are really going to be confused 
either way on this.

-- 
Ian Hickson   U+1047E)\._.,--,'``.fL
http://ln.hixie.ch/   U+263A/,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

Re: [whatwg] HTML5: compatible with all legacy Web browsers

[Erik Vorhes]

On Fri, Aug 7, 2009 at 8:28 AM, Aryeh Gregor wrote:
> I think the meaning of "compatible with all existing browsers" here is
> that HTML 5 does not *require* authors to break compatibility with any
> existing browser.
>

I agree completely with your interpretation of the phrase. HTML5 is
intended to enhance the web without breaking it, so noting (or even
emphasizing) how it's backwards-compatible is important and useful.

But the phrase should be clarified along similar lines to what you've
articulated. Maybe: "HTML5 can be written in such a way that it is
compatible with all browsers made after X date"?

Erik

Re: [whatwg] HTML5: compatible with all legacy Web browsers

[Aryeh Gregor]

I think the meaning of "compatible with all existing browsers" here is
that HTML 5 does not *require* authors to break compatibility with any
existing browser.  Obviously some new features of HTML 5 will not work
in some existing browsers -- otherwise there could be no new features
in the spec!  But it's designed to support graceful degradation
wherever possible, so that authors can use many of the new features
without breaking compatibility with any existing browser.  This is in
contrast to its erstwhile competitor XHTML 2 -- XHTML 2 cannot be used
in any legacy browsers, ever.

Clearer wording might be like, "HTML5 pages can be written to be
compatible with all legacy Web browsers."  Of course, "all legacy Web
browsers" does need to be construed to exclude Netscape Navigator 3
and such.  If you really want to be picky, it could be "all legacy Web
browsers that still see significant use."

Re: [whatwg] HTML5: compatible with all legacy Web browsers

[Erik Vorhes]

On Fri, Aug 7, 2009 at 5:39 AM, Simon Pieters wrote:
>
> What is it that is not compatible with which browser?
>

Any use of  outside of a  is broken in every
"modern" browser: IE6-8, Firefox 3-3.5, Safari 3-4, and Opera 9-10b
all break in interesting ways. For more details, see Remy Sharp's
"Legend not such a legend anymore"
.

Erik

Re: [whatwg] HTML5: compatible with all legacy Web browsers

[Simon Pieters]

On Thu, 06 Aug 2009 19:49:45 +0200, Elliotte Rusty Harold  
 wrote:



Section 1.7:

"The first such concrete syntax is "HTML5". This is the format
recommended for most authors. It is compatible with all legacy Web
browsers."

I challenge the claim that HTML5 is compatible with *all* legacy Web
browsers.


I guess it depends on the definition of "compatible".



I can produce valid HTML 4 documents today that are not
compatible with *all* legacy Web browsers.


That's irrelevant. Can you produce valid HTML5 documents today that are  
not compatible with all legacy Web browsers?


I guess the following is an example of a valid HTML5 document that is  
incompatible with legacy Web browsers:


   
   
   
   Hello world



I suggest this be weakened
to something like "is compatible with most Web browsers still in
active use today".


What is it that is not compatible with which browser?

--
Simon Pieters
Opera Software

[whatwg] HTML5: compatible with all legacy Web browsers

[Elliotte Rusty Harold]

Section 1.7:

"The first such concrete syntax is "HTML5". This is the format
recommended for most authors. It is compatible with all legacy Web
browsers."

I challenge the claim that HTML5 is compatible with *all* legacy Web
browsers. I can produce valid HTML 4 documents today that are not
compatible with *all* legacy Web browsers. I suggest this be weakened
to something like "is compatible with most Web browsers still in
active use today".

-- 
Elliotte Rusty Harold
elh...@ibiblio.org