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xmlcomments

Nested comments in XML?


Are these nested comments allowed in a XML file?

<!-- Making only one observation attempting to correct the error code -->
<!-- <component>
       <!-- Result observation template -->
            <!-- <id root="2.16.840.1.113883.19.5.10" extension="103220"/>
     </component> -->

Solution

  • No, the string -- is not permitted to appear within comments in XML. So the fact you have -- show up inside another comment is going to cause failures.

    And trying to post that answer also broke the text entry parsing ;)

    For further proof, check the W3C specification:

    http://www.w3.org/TR/2008/REC-xml-20081126/#sec-comments

    The phrase

    For compatibility, the string " -- " (double-hyphen) MUST NOT occur within comments.]

    appears in the first paragraph of the section on XML comments.