std.xml2 (collecting features) control character

[Adam D. Ruppe via Digitalmars-d]

On Thursday, 18 February 2016 at 16:54:10 UTC, Robert burner 
Schadek wrote:
> It does not, it has no prolog and therefore no EncodingInfo.

In that case, it needs to be valid UTF-8 or valid UTF-16 and it 
is a fatal error if there's any invalid bytes:

https://www.w3.org/TR/REC-xml/#charencoding

==
  It is a fatal error if an XML entity is determined (via default, 
encoding declaration, or higher-level protocol) to be in a 
certain encoding but contains byte sequences that are not legal 
in that encoding. Specifically, it is a fatal error if an entity 
encoded in UTF-8 contains any ill-formed code unit sequences, as 
defined in section 3.9 of Unicode [Unicode]. Unless an encoding 
is determined by a higher-level protocol, it is also a fatal 
error if an XML entity contains no encoding declaration and its 
content is not legal UTF-8 or UTF-16.
==