tag:blogger.com,1999:blog-11933937.post8771421414988107389..comments2008-05-21T03:35:31.398-05:00Stephen Chuhttp://www.blogger.com/profile/07181510921622947661noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-11933937.post-69564412231553737952008-05-21T03:35:00.000-05:002008-05-21T03:35:00.000-05:00@Justin:<BR/><BR/>Check this article out: <A HREF="http://www.stephenchu.com/2008/05/rails-composedof-validation.html" REL="nofollow">Rails composed_of validation</A>Stephen Chuhttp://www.blogger.com/profile/07181510921622947661noreply@blogger.comtag:blogger.com,1999:blog-11933937.post-3145711438370595162008-05-19T17:19:00.000-05:002008-05-19T17:19:00.000-05:00Great article Stephen,<BR/><BR/>I have one question about when to use composed_of. I have Address that is an aggregation of Locations. The types of Locations depend on the type of address. For example, a US_Postal_Address is an aggregation of City, State, Zip, etc Locations. An English_Postal_Address is an aggregation of City, County, Postal Code, ... Locations.<BR/><BR/>Other Address types <B>will</B> added, so I don't want to store locations within the definition of the Addresses table.<BR/><BR/>My question is, I'm not particularly interested in the identity of the Locations, I'm only interested in their values. However, the values do need to persist. Can composed_of aggregate other ActiveRecord models?<BR/><BR/>Second question, does this approach make sense to you?<BR/><BR/>Thanks for a great post and your help.<BR/><BR/>DamonDamonhttp://www.blogger.com/profile/05316112331439883003noreply@blogger.comtag:blogger.com,1999:blog-11933937.post-9918451909126201472008-03-20T09:17:00.000-05:002008-03-20T09:17:00.000-05:00Very helpful to see how fields_for and composed_of work together. You also allude to aggregate objects containing their 'own validation' code. I'd be curious to see a writeup on this, haven't been able to find much on the web.Justinnoreply@blogger.com