Differenciate between create/update and createItem/updateItem about knockout.mapping HOT 4 CLOSED

If the create callback is changed like you propose (i.e. providing the source array), what would be the additional benefit of the createItem/updateItem calls? What additional benefit would they bring?

I mean, since the create callback requires you to return a 'created' object, would that not be already the place to do your more complex mapping as in the example?

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Without the createItem/updateItem callback the original "key" callback would be rendered almost useless as it could not be used for custom item mappings (but with standard array mapping) anymore.

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That's true, since the key callback assumes that the key property can be found in both mapped and unmapped objects.
I'm still a bit hazy on what the exact sequence of callbacks would be in your proposal. Could you give an indication what your source, target and mapping options would look like in an 'ideal' situation?

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Talked on Skype, and concluded this idea is not necessary to implement.

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