i_know_regular_expressions.rb

pattern = begin
  delimeter            = "[-/.]+"
  
  century_prefix       = "(?:19|20)"
  under_ten            = "(?:0[1-9]+)"
  ten_to_twelve        = "(?:1[012]+)"
  ten_and_under_thirty = "(?:[12]+[0-9]+)"
  thirties             = "(?:3[01]+)"
  
  year                 = "(#{century_prefix}[0-9]{2})"
  month                = "(#{under_ten}|#{ten_to_twelve})"
  day                  = "(#{under_ten}|#{ten_and_under_thirty}|#{thirties})"
  
  /#{year}#{delimeter}#{month}#{delimeter}#{day}/
end

if pattern =~ "2010-02-17"
  year, month, day = $1, $2, $3
  # Insert multi-million dollar idea here
end