无法停止NSLinguisticTagger的阻止

Question

I'm using NSLinguisticTagger object and his method enumerateTagsInRange:scheme:options:usingBlock.

The problems is, when I'm using with a long string, without line breaks, I can't stop the block.

Here's my code to initiate the string and NSLinguisticTagger:

NSLinguisticTagger *tagger = [[NSLinguisticTagger alloc] initWithTagSchemes:@[NSLinguisticTagSchemeTokenType]
                                                                    options:NSLinguisticTaggerOmitOther | NSLinguisticTaggerOmitPunctuation | NSLinguisticTaggerOmitWhitespace];

[tagger setString:@"Lorem ipsum dolor sit er elit lamet, consectetaur cillium adipisicing pecu, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Nam liber te conscient to factor tum poen legum odioque civiuda."];

[tagger enumerateTagsInRange:NSMakeRange(0, [tagger.string length])
                      scheme:NSLinguisticTagSchemeTokenType
                     options:NSLinguisticTaggerOmitOther | NSLinguisticTaggerOmitPunctuation | NSLinguisticTaggerOmitWhitespace
                  usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop){

                       NSString *word = [tagger.string substringWithRange:tokenRange];

                       if ([word compare:@"lamet" options:NSCaseInsensitiveSearch] == NSOrderedSame) {
                            *stop = YES;
                       }
                  }
];

What I expected is, after I set *stop = YES the block stop his loop. But this isn't happening. The block jump to another sentence, but doesn't stop. If the string has line breaks (\\n) in the end of the sentences, the block stop as I expected (with the same code). But when string has line breaks, the block causes memory leaks.

Anyone have any idea what's happening and what I can try to block work has I expected?

The method of string enumerateSubstringsInRange:options:usingBlock: does not resolve my problem in my actual solution... I'd like to use NSLinguisticTagger...

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I made a contact with Apple Developer Technical Support with this problem and they oriented me to register this as a bug. So I made a bug report and I'm waiting for answer. Any news I'll edit this post.

Answer 1

Strange!

I was able to duplicate your problem. If you set stop to YES, it looks like enumerateTagsInRange still enumerates through the first word of any remaining sentences!

One way around the problem would be to change the call to enumerateTagsInRange to:

[tagger enumerateTagsInRange:NSMakeRange(0, [tagger.string length])
                      scheme:NSLinguisticTagSchemeTokenType
                     options:NSLinguisticTaggerOmitOther | NSLinguisticTaggerOmitPunctuation | NSLinguisticTaggerOmitWhitespace
                  usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop){

    if (*stop == NO) { // Only deal with the word if stop if not set to YES
        NSString *word = [tagger.string substringWithRange:tokenRange];

        if ([word compare:@"lamet" options:NSCaseInsensitiveSearch] == NSOrderedSame) {
            *stop = YES;
        }
    }
}];

See the added if statement.

Answer 2

I followed the same steps in iOS 7.1 and the problem does not occur anymore.

When I reported that to Apple as a bug they answered that may have been solved in iOS7. But only now I got time to test this again.