Line data    Source code

       1           0 : /*
       2             : 
       3             : OOFilteringEnumerator.h
       4             : By Jens Ayton
       5             : 
       6             : NSEnumerator which takes an existing enumerator and filters out the objects
       7             : that return NO from a given method. The method may take 0 or 1 arguments
       8             : 
       9             : Example of use:
      10             :         NSArray                 *cats = [self cats];
      11             :         NSEnumerator    *happyCatEnum = [[cats objectEnumerator] filteredWithSelector:@selector(isHappy)];
      12             :         id                              happyCat = nil;
      13             :         
      14             :         while ((happyCat = [happyCatEnum nextObject]))
      15             :         {
      16             :                 ...
      17             :         }
      18             : 
      19             : Filters can be trivially chained. For instance, to get happy red cats, use:
      20             :         NSEnumeratore   *happyRedCatEnum = [[[cats objectEnumerator]
      21             :                                                                                 filteredWithSelector:@selector(isHappy)]
      22             :                                                                                 filteredWithSelector:@selector(hasColor:)
      23             :                                                                                                  andArgument:[NSColor redColor]];
      24             : 
      25             : Objects that do not respond to the filter selector are treated as if they had
      26             : returned NO.
      27             : 
      28             : Bonus feature: adds NSArray-like (but non-exception-throwing)
      29             : makeObjectsPerformSelector: to all enumerators.
      30             : 
      31             : 
      32             : Copyright (C) 2008-2013 Jens Ayton
      33             : 
      34             : Permission is hereby granted, free of charge, to any person obtaining a copy
      35             : of this software and associated documentation files (the "Software"), to deal
      36             : in the Software without restriction, including without limitation the rights
      37             : to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
      38             : copies of the Software, and to permit persons to whom the Software is
      39             : furnished to do so, subject to the following conditions:
      40             : 
      41             : The above copyright notice and this permission notice shall be included in all
      42             : copies or substantial portions of the Software.
      43             : 
      44             : THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
      45             : IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      46             : FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
      47             : AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      48             : LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
      49             : OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
      50             : SOFTWARE.
      51             : 
      52             : */
      53             : 
      54             : #import "OOCocoa.h"
      55             : 
      56             : 
      57           0 : @interface OOFilteringEnumerator: NSEnumerator
      58             : {
      59             : @private
      60           0 :         NSEnumerator            *_underlyingEnum;
      61           0 :         SEL                                     _selector;
      62           0 :         id                                      _argument;
      63           0 :         BOOL                            _takesArgument;
      64             : }
      65             : 
      66           0 : + (id) filterEnumerator:(NSEnumerator *)enumerator withSelector:(SEL)selector;
      67           0 : + (id) filterEnumerator:(NSEnumerator *)enumerator withSelector:(SEL)selector andArgument:(id)argument;
      68             : 
      69           0 : - (id) initWithUnderlyingEnumerator:(NSEnumerator *)enumerator
      70             :                                            withSelector:(SEL)selector
      71             :                                          takingArgument:(BOOL)takesArgument
      72             :                                           argumentValue:(id)argument;
      73             : 
      74             : @end
      75             : 
      76             : 
      77             : @interface NSEnumerator (OOFilteringEnumerator)
      78             : 
      79           0 : - (id) filteredWithSelector:(SEL)selector;
      80           0 : - (id) filteredWithSelector:(SEL)selector andArgument:(id)argument;
      81             : 
      82             : @end
      83             : 
      84             : 
      85             : @interface NSArray (OOFilteringEnumerator)
      86             : 
      87           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector;
      88           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector andArgument:(id)argument;
      89             : 
      90             : @end
      91             : 
      92             : 
      93             : @interface NSSet (OOFilteringEnumerator)
      94             : 
      95           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector;
      96           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector andArgument:(id)argument;
      97             : 
      98             : @end
      99             : 
     100             : 
     101             : @interface NSDictionary (OOFilteringEnumerator)
     102             : 
     103           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector;
     104           0 : - (id) objectEnumeratorFilteredWithSelector:(SEL)selector andArgument:(id)argument;
     105             : 
     106           0 : - (id) keyEnumeratorFilteredWithSelector:(SEL)selector;
     107           0 : - (id) keyEnumeratorFilteredWithSelector:(SEL)selector andArgument:(id)argument;
     108             : 
     109             : @end
     110             : 
     111             : 
     112             : @interface NSEnumerator (OOMakeObjectsPerformSelector)
     113             : 
     114           0 : - (void)makeObjectsPerformSelector:(SEL)selector;
     115           0 : - (void)makeObjectsPerformSelector:(SEL)selector withObject:(id)argument;
     116             : 
     117             : @end