This GIST is to help explain the behaviour of NSAttributedString's "initWithData:options:documentAttributes:error:" when used with NSHTMLDocumentType.At first glance, one would expect the output here to be "1, 2, 3", But after some careful reading of the documentation, and if you run the code here, we find that not to be true.

NSHTMLTextDocumentType

dispatch_async(dispatch_get_main_queue(), ^{

    NSLog(@"3");
});

NSLog(@"1");

[[NSAttributedString alloc] initWithData:[@"<span>html!</span>" dataUsingEncoding:NSUTF8StringEncoding]
                                 options:@{
                                           NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,
                                           }
                      documentAttributes:nil
                                   error:nil];

NSLog(@"2");

/*
Expected output: 1 2 3
Actual Output: 1 3 2
*/