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ios - CoreData predicate: string property length?

Say if I have an entity Fragment, it has an attribute 'text' which is a string, I want to query the list of Fragment whose text is of length 5:

[NSPredicate predicateWithFormat:@"position == %@ AND text.length == %d", pos, 5];

It does not work (ie returns no result), but if I remove text.length in the query it works and I'm certain that there are texts of length 5, so what do I need to change it to?

Thanks!

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There is no length attribute for strings in the NSPredicate. Use regex instead. Your predicate should look as follows:

[NSPredicate predicateWithFormat:@"position == %@ AND text MATCHES %@", pos, @".{5}"];

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