Errata: Entities cannnot begin with a BOM - can only be preceded by a BOM

Section 4.3.3. of XML 1.0 fifth edition contains the following phrase, 
which sounds as though an entity (for example an external entity) may 
begin with a Byte Order Mark:

   “an entity which begins with neither a Byte Order Mark
    nor an encoding declaration”

While it is not 100% clear what kind of ”entity” it is meant, the 
phrase is misleading because, as pointed out in the same section, and 
in  the document production in section 2[2][3], and as re-emphasized by 
3023bis (XML media types)[4], the BOM (unlike an encoding declaration) 
is not part of the external entity.

So an entity cannot “begin” with a BOM, it can only be preceded by a 
BOM. (By analogy, when there is a transport protocol, such as HTTP, we 
do not say the entity “begins” 
with a Content-Type declaration.)

Hence, please update the above phrase to reflect this point, for 
instance by adjusting it roughly like this:

“an entity which is neither preceded by a Byte Order Mark nor begins 
with an encoding declaration”

[1] http://www.w3.org/TR/REC-xml/#charencoding

[2] http://www.w3.org/TR/REC-xml/#dt-xml-doc

[3] http://www.w3.org/TR/REC-xml/#NT-document

[4] 
http://tools.ietf.org/html/draft-ietf-appsawg-xml-mediatypes-06#section-3.3

-- 
leif halvard silli

Received on Thursday, 19 December 2013 02:21:33 UTC