class String

def to_date

"12/13/2012".to_date # => ArgumentError: invalid date
"2012-12-13".to_date # => Thu, 13 Dec 2012
"01/01/2012".to_date # => Sun, 01 Jan 2012
"1-1-2012".to_date # => Sun, 01 Jan 2012

Converts a string to a Date value. 
def to_date
  ::Date.parse(self, false) unless blank?
end