re = /<html\>(?!html)([\s\S]*)<\/html\>/
str = '
This is text
<html>
<div>
some content
</div>
</html>
This is more text
<html>
<div>
some content
</div>
</html>
'
# Print the match result
str.match(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html