text: //
  // NSDate+Helper.h
  //
  // Created by Billy Gray on 2/26/09.
  // Copyright (c) 2009, 2010, ZETETIC LLC
  // All rights reserved.
  // 
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are met:
  //     * Redistributions of source code must retain the above copyright
  //       notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above copyright
  //       notice, this list of conditions and the following disclaimer in the
  //       documentation and/or other materials provided with the distribution.
  //     * Neither the name of the ZETETIC LLC nor the
  //       names of its contributors may be used to endorse or promote products
  //       derived from this software without specific prior written permission.
  // 
  // THIS SOFTWARE IS PROVIDED BY ZETETIC LLC ''AS IS'' AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  // DISCLAIMED. IN NO EVENT SHALL ZETETIC LLC BE LIABLE FOR ANY
  // DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  // (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  // LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  // ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  
  #import <Foundation/Foundation.h>
  
  @interface NSDate (Helper)
  
  - (NSUInteger)daysAgo;
  - (NSUInteger)daysAgoAgainstMidnight;
  - (NSString *)stringDaysAgo;
  - (NSString *)stringDaysAgoAgainstMidnight:(BOOL)flag;
  - (NSUInteger)weekday;
  
  + (NSDate *)dateFromString:(NSString *)string;
  + (NSDate *)dateFromString:(NSString *)string withFormat:(NSString *)format;
  + (NSString *)stringFromDate:(NSDate *)date withFormat:(NSString *)string;
  + (NSString *)stringFromDate:(NSDate *)date;
  + (NSString *)stringForDisplayFromDate:(NSDate *)date;
  + (NSString *)stringForDisplayFromDate:(NSDate *)date prefixed:(BOOL)prefixed;
  
  - (NSString *)string;
  - (NSString *)stringWithFormat:(NSString *)format;
  - (NSString *)stringWithDateStyle:(NSDateFormatterStyle)dateStyle timeStyle:(NSDateFormatterStyle)timeStyle;
  
  - (NSDate *)beginningOfWeek;
  - (NSDate *)beginningOfDay;
  - (NSDate *)endOfWeek;
  
  + (NSString *)dateFormatString;
  + (NSString *)timeFormatString;
  + (NSString *)timestampFormatString;
  + (NSString *)dbFormatString;
  
  @end