Separate Full Sentences in a block of NSString text
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I have been trying to use Regular Expression to separate full sentences in a big block of text. I can't use the componentsSeparatedByCharactersInSet because it will obviously fail with sentences ending in ?!, !!, ... I have seen some external classes to do componentSeparateByRegEx but I prefer doing it without adding an external library. 

Here is a sample input 
**Hi, I am testing. How are you? Wow!! this is the best, and I am happy.** 

The output should be an array 

first element: **Hi, I am testing.**

second element:  **How are you?**

third element: **wow!!**

forth element: **this is the best, and I am happy.** 

This is what I have but as I mentioned it shouldn't do what I intend. Probably a regular expression will do a much better job here. 

    -(NSArray *)getArrayOfFullSentencesFromBlockOfText:(NSString *)textBlock{
        NSMutableCharacterSet *characterSet = [[NSMutableCharacterSet alloc] init];
        [characterSet addCharactersInString:@".?!"];  
        NSArray * sentenceArray = [textBlock componentsSeparatedByCharactersInSet:characterSet];                                   
        return sentenceArray;  
    }

Thanks for your help, 
