- From: Alex Milowski <alex@milowski.org>
- Date: Fri, 8 Apr 2011 16:05:47 -0700
- To: XProc WG <public-xml-processing-model-wg@w3.org>
On Fri, Apr 8, 2011 at 1:26 AM, Henry S. Thompson <ht@inf.ed.ac.uk> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > As long as entity definitions for e.g. math and accented characters > are typically acquired via the external subset, I don't see how we can > back down on that. > I just took a look at what MathML 3 has to say about entity usage. While the language of the specification seems rather neutral at first glance, it does say: "An XML fragment that uses an entity reference which is not defined in a DTD is not well-formed; therefore it will be rejected by an XML parser. For this reason every fragment using entity references must use a DOCTYPE declaration which specifies the MathML DTD, or a DTD that at least declares any entity reference used in the MathML instance. The need to use a DOCTYPE complicates inclusion of MathML in some documents. However, entity references can be useful for small illustrative examples." That's hardly a ringing endorsement for use of entity references for characters. In the end, they map to unicode characters: "While a long process of review and adoption by UTC and ISO/IEC of the characters of special interest to mathematics and MathML is now complete, more characters may be added in the future." In the case of the web browser, using character references or direct encoding of Unicode characters is going to be much more interoperable. I can certainly tell you the difficulties in getting the entity declarations internalized for XHTML (let along HTML 5) will be great. As such, I wouldn't personally endorse preserving the use of external DTD subsets as a path forward. By making this "recommended", I think we are endorsing that. I have brought this same issue up in our past discussions but it has become more acute, at least for me, as I investigate implementations with web browsers. -- --Alex Milowski "The excellence of grammar as a guide is proportional to the paucity of the inflexions, i.e. to the degree of analysis effected by the language considered." Bertrand Russell in a footnote of Principles of Mathematics
Received on Friday, 8 April 2011 23:06:15 UTC