re = /^(?:[a-zA-Z0-9]+-){3,}[a-zA-Z0-9]+$/m
str = 'AA3A-123-NNN-D
12-OOO-12455-AS
AA3A-123-NNN-Dasdfasfd-23423423_234234
12-OOO-12455-AS123124-124123
123142-123123-3afdsafs'
# 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