next-property-change error

[Xavier Sanchez]

Hello all,

I'm writing an html to LaTeX program in elisp that includes the
following function:

(defun xhtlatex-href ()
  (re-search-forward "=[\"'\n]*" nil t)
  (let ((url (buffer-substring (point) (next-property-change
(point)))))
    (sgml-skip-tag-forward 1)
    (insert "}")
    (sgml-skip-tag-backward 1)
    (sgml-delete-tag 1)
    (insert (concat "\\href{" url "}{"))))

There's another function that finds the "<a", then calls the above
function if "href" follows.
When I load the file and run the program the first time it stops at
the "<a" and gives the error:

let: Wrong type argument: integer-or-marker-p, nil

This only happens once; subsequent runs work as expected.

For what it's worth, I've found that doing a minibuffer evaluation of
(next-property-change (point)) at some point in the buffer before the
first run of the program enables execution up to that point.

I haven't made sense of this yet, can anyone else?

Thanks