evaluate_condition

# File activerecord/lib/active_record/validations.rb, line 348
      def evaluate_condition(condition, record)
        case condition
          when Symbol; record.send(condition)
          when String; eval(condition, record.send(:binding))
          else
            if condition_block?(condition)
              condition.call(record)
            else
              raise(
                ActiveRecordError,
                "Validations need to be either a symbol, string (to be eval'ed), proc/method, or " +
                "class implementing a static validation method"
              )
            end
          end
      end