re = /<tr[^>]*>((?!<\/tr>|<td>|<\/td>).)*<\/tr>/
str = '<tr asdf>
<td>
<hello>
</td>
</tr>
<tr asdf>
</tr>'
# Print the match result
str.scan(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