dynamically defined ar classes

rubyonrails-talk
1

I'm not sure I completely understand why you want to do this. If it's to keep things DRY I would question whether this is a bit of an OTT optimisation. The models you specified seem generally unrelated and as your application grows, you will most likely find that this method becomes a hindrance rather than beneficial.

I may be wrong of course, but generally separating your models out and defining them individually is a good plan long term. If you want something to get started with, I would suggest looking at Dr Nic's Magic Models (http://magicmodels.rubyforge.org/). This is a plugin that automatically creates models from the database schema. Even if it's not what you're looking for, you may pick up a few tips for what you're trying to do by having a look through the source code.

Steve

2

So: can this work?

Yeah, but not in the way you have. You can use the 'eval' command to execute ruby code to create your classes:

['MyNewClass'].each do |klass|    model_string = "class #{klass} < ActiveRecord::Base; def say_hello; 'Hello!'; end; end;"    eval(model_string) end

my_new_class = MyNewClass.new my_new_class.say_hello -> "Hello!"

You can build up the string using the values defined in your hashes and arrays then execute. I'm not sure what effect all this will have on the execution time of you app, but try it out and see how you get on.

Steve