re = /AX[BCD][EFG](\d[A-Z\d]{4}|[A-Z\d]\d[A-Z\d]{3}|[A-Z\d]{2}\d[A-Z\d]{2}|[A-Z\d]{3}\d[A-Z\d]|[A-Z\d]{4}\d)/m
str = 'AXBE1BCDE
AXBEA2CDE
AXBEAB3DE
AXBEABC4E
AXBEABCD5
AXBE1BCD5
AXBE12345
AXBEABCDE'
# 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