return nil
end
+ # Parse a float, raising a specified exception on failure
+ def self.parse_float(str, klass, *args)
+ Float(str)
+ rescue
+ raise klass.new(*args)
+ end
+
# Construct a random token of a given length
def self.make_token(length = 30)
chars = 'abcdefghijklmnopqrtuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'