Source
(defun unescape-as-html (string)
(with-output-to-string (unescaped)
(loop
for offset upfrom 0 below (length string)
for char = (aref string offset)
if (char= #\& char)
do (progn
(aif (position #\; string :start offset)
(let ((escape-tag (subseq string offset (1+ it))))
(aif (gethash escape-tag *html-entites*)
(progn
(princ it unescaped)
(incf offset (1- (length escape-tag))))
(if (char= #\# (aref escape-tag 1))
;; special code, ignore
(restart-case
(warn 'unknown-char-escape :what escape-tag)
(continue-delete ()
:report "Continue processing, delete this char."
(incf offset (1- (length escape-tag)))))
(restart-case
(error 'unknown-html-entity :what escape-tag)
(continue-as-is ()
:report "Continue processing, leaving the string as is."
(write-char #\& unescaped))
(continue-delete ()
:report "Continue processing, delete this entity."
(incf offset (1- (length escape-tag))))))))
(restart-case
(error 'unterminated-html-entity
:what (subseq string offset
(min (+ offset 20)
(length string))))
(continue-as-is ()
:report "Continue processing, leave the string as is."
(write-char #\& unescaped)))))
else do (write-char char unescaped))))Source Context