Model Reflection Overview

We all use ActiveRecord Reflection on the fly while programming, since we declare all the relations in the model and we are considering it as obvious.
i tried to search and see if there is a way to find those reflections and to alter it in runtime.

Model.reflections

i found this collection which contains all the information about the current model reflections.
for example.

• .macro: this will return the type of the current reflection (:has_many, etc..)


• .primary_key_name: the reflection primary key


• .options: the reflection SQL join options


• etc. etc.

for example, the following code will show me all the reflections for a model named Article:

1. >> y Article.reflections.values.collect {|e| e.macro.to_s  + " => " + e.primary_key_name.to_s }  
2. ---   
3. - has_many => taggee_id  
4. - belongs_to => layout_id  
5. - has_many => article_id  
6. - has_one => subject_id  
7. - belongs_to => user_id  
8. - has_many => taggee_id  
9. => nil