class Country < ActiveRecord::Base
#alias_method :name, :langEN # here fails
#alias_method :name=, :langEN=
#attr_accessible :name
def name; langEN end # here works
end
In first call alias_method fails with:
NameError: undefined method `langEN' for class `Country'
I mean it fails when I do for example Country.first.
But in console I can call Country.first.langEN successfully, and see that second call also works.
What am I missing?
ActiveRecord uses method_missing (AFAIK via ActiveModel::AttributeMethods#method_missing) to create attribute accessor and mutator methods the first time they're called. That means that there is no langEN method when you call alias_method and alias_method :name, :langEN fails with your "undefined method" error. Doing the aliasing explicitly:
def name
langEN
end
works because the langEN method will be created (by method_missing) the first time you try to call it.
Rails offers alias_attribute:
alias_attribute(new_name, old_name)
Allows you to make aliases for attributes, which includes getter, setter, and query methods.
which you can use instead:
alias_attribute :name, :langEN
The built-in method_missing will know about aliases registered with alias_attribute and will set up the appropriate aliases as needed.