henrik

class Luhn
  def self.checksum(number)
    digits = number.to_s.reverse.scan(/\d/).map { |x| x.to_i }
    digits = digits.each_with_index.map { |d, i|
      d *= 2 if i.even?
      d > 9 ? d - 9 : d
    }
    sum = digits.inject(0) { |m, x| m + x }
    mod = 10 - sum % 10
    mod==10 ? 0 : mod

nikreiman

Day
---
%a	weekday, abbreviated	Tue
%A	weekday, full	Tuesday
%d	day of the month (dd), zero padded	22
%e	day of the month (dd)	22
%j	day of year, zero padded	001-366
%u	day of week starting with Monday (1), i.e. mtwtfss	2
%w	day of week starting with Sunday (0), i.e. smtwtfs	2

lucasfais

Sublime Text 2 – Useful Shortcuts (Mac OS X)

General

⌘T	go to file
⌘⌃P	go to project
⌘R	go to methods
⌃G	go to line
⌘KB	toggle side bar
⌘⇧P	command prompt