[cxml-devel] ystream-unicode-p errors when serializing to character-stream

[Nathan Bird]

With git head I get an error with the following:

(with-output-to-string (stream)
    (let ((doc (dom:create-document
              'rune-dom:implementation
              nil nil
              (dom:create-document-type
               'rune-dom:implementation
               "html"
               "-//W3C//DTD XHTML 1.0 Transitional//EN"
               "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"))))
      (dom:map-document (chtml:make-character-stream-sink stream)
            doc
            :include-xmlns-attributes nil
            :include-doctype :full-internal-subset
            )))

The error as far as I've been able to track it down, is that the ystream 
created has a encoding slot, that is never filled. Then 
#'runes::ystream-unicode-p chokes when trying to inspect the encoding.  
We solved the error by testing the target stream when the encoding slot 
is null:

(defun ystream-unicode-p (ystream)
  (let ((enc (ystream-encoding ystream)))
    (if enc
    (or (eq enc :utf-8)
        (eq (babel-encodings:enc-name enc) :utf-16))
    #+rune-is-character (eq 'character (stream-element-type 
(ystream-target-stream ystream))))))

But I'm not sure that it is sound, and that function looks kind of 
strange anyways: what if encoding was the symbol :utf-16 or a 
babel-encoding object with the name :utf-8? It looks like the shift to 
babel-encodings is still somewhat a work-in-progress, does this help?

We found this today when we switched from asdf-installed version to git 
HEAD because there was a problem with & getting escaped that looks like 
it is already fixed in git.