re = /^(?<ALL>(?!.*H-\d{4}\b).*|.*?(?:(?<ID>H-\d{4})\b).*)$/m
str = 'Sample line with H-5722 id
Sample line without id'
# 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