re = /^((?:\d{6})(?:(?:,[^\n]\d{6}){1,})?)$/m
str = '123456
123456, 456789, 987654
1
,
123456, 123456, 987654,
123456, 123456
123456, 456789, 987654, 123456, 1234567
123456, 456789, 987654, 123456, 123456, 345678
1,
,
,
123,'
# 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