newlispfanclub.alh.net

Posted: **Wed Aug 06, 2008 5:29 pm**

I'm working on an application where I need to frequently alter the xml-type-tags and want to return to a default, so I wrote a macro, with-xml-type-tags:

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(define-macro (with-xml-type-tags)
  (letex ((old-tags (xml-type-tags))
          (new-tags (args 0))
          (body (cons 'begin (rest (args)))))
    (apply 'xml-type-tags 'new-tags)
    (let ((res body))
      (apply 'xml-type-tags 'old-tags)
      res)))

I'm getting some odd results using it:

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(println "1: " (xml-type-tags))
(println "2: "
  (with-xml-type-tags (nil nil nil nil)
    (xml-type-tags)))
(println "3: " (xml-type-tags))

...prints out:

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1: ("TEXT" "CDATA" "COMMENT" "ELEMENT") ; before macro
2: (nil nil nil nil) ; in macro body
3: ("\000\0005{" "COMME" "ELEMENT" "\000\0005{\000\000\000") ; after macro

That looks like some sort of weird alignment problem... any ideas?

Posted: **Wed Aug 06, 2008 8:09 pm**

The problem is with the xml-type-tags, which only accepts constants safely.

Until this is fixed the only safe way is, to use xml-type-tags with constants as parameters.

I will release a fix soon as a development release.

newlispfanclub.alh.net

Problem in xml-type-tags

Problem in xml-type-tags