re = /^(([A-Z]{2}-\d{2}-(\d{2}|[A-Z]{2}))|(\d{2}-(\d{2}-[A-Z]{2}|[A-Z]{2}-\d{2})))$/m
str = 'AA-00-00
00-00-AA
00-AA-00
AA-00-AA
AA-00-A2
AAA-00-AA
AA-AA-00'
# 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