Question

I have the following code that parses HTML text and trims (or strips) the paragraphs that are empty. It’s similar to .strip on a String object.

doc = Nokogiri::HTML::DocumentFragment.parse(html)

# repetition that I want to collapse
doc.css('p').each do |p|
  if all_children_are_blank?(p)
    p.remove
  else
    break
  end
end

# repetition that I want to collapse
doc.css('p').reverse_each do |p|
  if all_children_are_blank?(p)
    p.remove
  else
    break
  end
end

doc.to_s.strip

Is there a more elegant way to prevent code that I’ve labelled with comments to be duplicated and adhere to principles of code-reuse?

Here is what I’ve come up with but I’m not happy with it yet and wanted to see if there is something better:

doc = Nokogiri::HTML::DocumentFragment.parse(html)

doc.css('p').each do |p|
  if stop(p) then break end
end

doc.css('p').reverse_each do |p|
  if stop(p) then break end
end

doc.to_s.strip

def self.stop(p)
  if all_children_are_blank?(p)
    p.remove
    false
  else
    true
  end
end

Answer 1

If I understand what you’re looking for, you would like a simpler way to iterate over the elements you’re looking at, in order to remove blank p elements.

Here is a straightforward way to collapse what you’ve written, without doing a whole lot different:

doc.tap do |d|
  [:each, :reverse_each].each do |sym|
    d.css("p").public_send(sym) do |p|
      if blank_children?(p)
        p.remove
      else
        break
      end
    end
  end
end.to_s.strip

I have not tested this out, so you might need to tweak it a little. If this were production code, I would probably decompose it into one or more method calls in order to keep things clear.