I’m having a difficult time wrapping my head around a set of models
and their associations and seeing how they map into Rails. I’ll try
to lay out my problem using the has_many and belongs_to structures. I
have a RuleSpace, a Rule, and a Subject.
A RuleSpace has_many Rules
A RulesSpace has_many Subjects through Rules
A Rule belongs_to (many) RuleSpaces
A Rule has_many Subjects
A Subject has_one Rule
A Subject has_one RuleSpace
So given a single Subject I should be able to find a single Rule and
a single RuleSpace. Going the other way, given a RuleSpace I should
find many Subjects.
I’m thinking the model definitions should look like this:
class RuleSpace < AR::Base
has_many :subjects, :through => :rules
class Rule < AR::Base
class Subject < AR::Base
has_many :rule_spaces, :through => :rules
I’m not sure at all that a call to Subject.rule_spaces will return
only a single element. Will #has_one enforce this? Is this legal?