Since the new deprecation policy<\/a> the A few days ago we started a discussion about the removal of the In this presentation<\/a>, Aaron Patterson<\/a> talks about three types of features: Cosmetic, Refactoring, and Course Correction. Aaron defines cosmetic features as a feature that adds dubious value and unknown debt (I highly recommend that you watch the whole presentation to see more about these types of features). This is exactly what I think about The removal plan is simple, deprecate in 3.2 and remove in 4.0. This means that you need to stop using this feature and implement it in another way.<\/p>\n The Rails team have chosen this path because this feature can be implemented using plain ruby methods for getters and setters. You will see how in the next section.<\/p>\n In the simplest case, when you have only one attribute and needs to instantiate an object with the value of this attribute, you can use the To use it with multiple attributes you can do the following:<\/p>\n I already talked about what this removal can provide to Rails maintainers, but what benefits does it bring to Rails developers?<\/p>\n I think that the best advantages are:<\/p>\n I strongly recommend that you read the whole discussion in the pull request<\/a>. You will find more examples and additional information there.<\/p>\ncomposed_of<\/code> removal was reverted. We are still discussing the future of this feature.<\/p>\nThe reason<\/h3>\n
composed_of<\/code><\/a> method from Active Record. I started this discussion because when I was tagging every Rails issue according to its framework, I found some<\/a> of them<\/a> related<\/a> to composed_of<\/code><\/a>, that are not only hard to fix but would add more complexity for a feature that, in my opinion, is not adding any visible value to the framework.<\/p>\ncomposed_of<\/code>. At this time this feature is adding more debt than value to the Rails code base and applications, so the Rails team have decided to remove this method.<\/p>\nThe plan<\/h3>\n
Implementation<\/h3>\n
serialize<\/code> feature with a custom serializer:<\/p>\n\nclass MoneySerializer\n def dump(money)\n money.value\n end\n\n def load(value)\n Money.new(value)\n end\nend\n\nclass Account < ActiveRecord::Base\n serialize :balance, MoneySerializer.new\nend\n<\/pre>\n
\nclass Person < ActiveRecord::Base\n def address\n @address ||= Address.new(address_street, address_city)\n end\n\n def address=(address)\n self[:address_street] = address.street\n self[:address_city] = address.city\n \n @address = address\n end\nend\n<\/pre>\n
Benefits for Rails developers<\/h3>\n
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:converter<\/code>, :constructor<\/code> and :allow_nil<\/code>.<\/li>\n<\/ul>\nWrapping up<\/h3>\n