Calculated fields are usually not stored in the database. But, in many cases, you would want to treat them just like attributes - serializing them into the xml/json representation, discarding them if they appear on the incoming xml/json payloads, lazily initializing them (in case you are loading them from an expensive ActiveResource call), etc. You will also want to access them by either methods or [] notation.
The major distinguishing features of SoftAttributes are:
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To not pollute the attributes hash by putting non-persisted variables in them.
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But at the same time, to maintain a list of attributes that can get accessed.
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These attributes could be lazily loaded (and cached in the instance, once they are retrieved - to avoid multiple ActiveResource calls)
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To provide an easy way to inject them into the xml/json payload as needed.
class Foo
#will define a setter method that ignores the param noop_setter :bar
end
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Copyright © 2010 Vijay Aravamudhan
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