Lightweight Migrations in Core Data Tutorial | Ray Wenderlich

Learn how to keep your data models up-to-date with this Core Data migrations tutorial!

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Can someone explain what is Value Transformer and Module?

@astralbodies Can you please help with this when you get a chance? Thank you - much appreciated! :]

Okay. Value Transformer is the class that inherited from NSValueTransformer and will cast one data type to another. But still what is module?

@astralbodies Do you have any feedback about this? Thank you - much appreciated! :]

Hey @observerward - so sorry I missed your question and left you hanging! Thanks @shogunkaramazov for the nudge.

Module is the Swift module that the model classes exist in. You can leave it set to “Current Product Module” if all of your model classes live in the same project/module that the model is in. 99.9% of the time this will be true for you, and definitely is the case with the book.

Take a look here for more information on modules in Swift.

Thanks for reply! Very appreciate!

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