I have an input string in html that needs to be parsed and written to DITA compatible XML.

Input:

<p>Line with following newline<br>Line with two following newlines<br><br>Line with no following newline</p>

Desired Output:

<p>Line with following newline<?linebreak?>Line with two following newlines<?linebreak?><?linebreak?>Line with no following newline</p>

package require tdom

set xml {<p>Line with following newline<br>Line with two following newlines<br><br>Line with no following newline</p>}

puts "Input:"
puts "$xml"

set doc [dom parse -html -keepEmpties $xml]
set root [$doc documentElement]

foreach node [$root getElementsByTagName br] {
    $node delete
    #$node appendXML "<?linebreak?>"

}

puts "Output:"
puts [$doc asXML -indent none]

If I uncomment #$node appendXML "<?linebreak?>", the script fails. I’m new to tdom but not tcl. Or….maybe someone has a different idea on how to preserve linebreaks in XML, specifically DITA.