Feature #12447
Updated by mrkn (Kenta Murata) almost 8 years ago
I sometimes want to extract digits of place-value notation of integer numbers. For example: ``` 12345.digits #=> [5, 4, 3, 2, 1] 12345.digits(100) #=> [45, 23, 1] ``` One typical use case is calculating checksum digit. I found some code extracting digits by the way like `int.to_s.chars.map(&:to_i)`. - https://github.com/joeljunstrom/ruby_luhn/blob/master/lib/luhn.rb#L43 - https://github.com/elitwin/check_digit/blob/master/lib/check_digit/damm.rb#L28 - https://github.com/elitwin/check_digit/blob/master/lib/check_digit/luhn.rb#L14 - https://github.com/elitwin/check_digit/blob/master/lib/check_digit/verhoeff.rb#L42 Introducing Integer#digits can reduce needless string allocation in such cases. The patch was pushed into the repository in github. https://github.com/mrkn/ruby/commit/5dce32d