alvim
2007-Jul-15 11:12 UTC
A copy of "Module X" has been removed from the module tree but is still active!
Hi!
This will be a long one, sorry about that.
I''ve been playing with Ruby and Rails for the last year, but only
getting a little more "serious" now. I like how one line in a model
("has_many", for example) will create several methods for you, and I
had a need to do something similar myself, so I decided to give it a
shot, looking at other people''s codes. Please bear in mind I am no
expert in Ruby or Rails, but this is what I tried:
[code]
First, I include my model in ActiveRecord::Base on startup, by doing
this:
(/config/environment.rb, last line)
ActiveRecord::Base.send(:include, MyTest)
Then the module itself:
(/lib/my_test.rb)
module MyTest
def self.included(base)
base.extend(ClassMethods)
end
module ClassMethods
def do_my_stuff
module_eval do
include MyTest::InstanceMethods
end
end
end
# I actually have different instance method modules, this is why I
went with this way
module InstanceMethods
def my_cool_method; "COOL!"; end
def my_other_cool_method; "COOLER!"; end
end
end
Finally, the actual model:
(/app/models/my_model.rb)
class MyModel < ActiveRecord::Base
do_my_stuff # now every MyModel instance should have my_cool_method
end
Controller:
(/app/controllers/main_controller.rb)
class MainController < ApplicationController
def index
@mymodel = MyModel.find(:first)
render :text => @mymodel.my_cool_method
end
end
[/code]
After all this, I run to http://localhost:3000/main/index
First run outputs "COOL!", as expected
Second run:
A copy of MyTest::ClassMethods has been removed from the module tree
but is still active!
I''ll spare you the full trace, but it begins like this:
C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/
dependencies.rb:237:in `load_missing_constant''
C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/
dependencies.rb:452:in `const_missing''
#{RAILS_ROOT}/lib/my_test.rb:9:in `do_my_stuff''
#{RAILS_ROOT}/lib/my_test.rb:8:in `module_eval''
#{RAILS_ROOT}/lib/my_test.rb:8:in `do_my_stuff''
#{RAILS_ROOT}/app/models/my_model.rb:8
Well, that''s about it. I''ve googled the message, been through
several
Trac tickets and forum postings, but all of them seem to be from
before rails 1.2.3 (which is the version I''m using) and related to
plugins who had controllers, and before_filters, and the such. I don''t
have any of those, so this is why I''m asking here.
I''m using Rails 1.2.3 and ruby 1.8.6 (2007-03-13 patchlevel 0) [i386-
mswin32]
I appreciate any help you can give me with this.
Thanks,
Marcelo Alvim.
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alvim
2007-Jul-17 04:09 UTC
Re: A copy of "Module X" has been removed from the module tree but is still active!
Well, I discovered what it was. The answer was somewhat buried in the Rails Trac, so I am going to post it here to help future people that have the same problem. It has to do with Rails loading and unloading stuff in development mode. If you do a "require ''lib/my_test'' " in your environment.rb, it goes away. Yes, stuff in the lib directory is supposed to be automatically loaded, thus eliminating the need for manual requires. And stuff in the lib directory IS, in fact, loaded. The reloading mechanism is the one that is kind of funny. Well, this does the trick. See you guys, Marcelo Alvim. On Jul 15, 4:12 am, alvim <mal...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi! > > This will be a long one, sorry about that. > > I''ve been playing with Ruby and Rails for the last year, but only > getting a little more "serious" now. I like how one line in a model > ("has_many", for example) will create several methods for you, and I > had a need to do something similar myself, so I decided to give it a > shot, looking at other people''s codes. Please bear in mind I am no > expert in Ruby or Rails, but this is what I tried: > > [code] > First, I include my model in ActiveRecord::Base on startup, by doing > this: > (/config/environment.rb, last line) > ActiveRecord::Base.send(:include, MyTest) > > Then the module itself: > (/lib/my_test.rb) > module MyTest > def self.included(base) > base.extend(ClassMethods) > end > module ClassMethods > def do_my_stuff > module_eval do > include MyTest::InstanceMethods > end > end > end > # I actually have different instance method modules, this is why I > went with this way > module InstanceMethods > def my_cool_method; "COOL!"; end > def my_other_cool_method; "COOLER!"; end > end > end > > Finally, the actual model: > (/app/models/my_model.rb) > class MyModel < ActiveRecord::Base > do_my_stuff # now every MyModel instance should have my_cool_method > end > > Controller: > (/app/controllers/main_controller.rb) > class MainController < ApplicationController > def index > @mymodel = MyModel.find(:first) > render :text => @mymodel.my_cool_method > end > end > [/code] > > After all this, I run tohttp://localhost:3000/main/index > First run outputs "COOL!", as expected > > Second run: > > A copy of MyTest::ClassMethods has been removed from the module tree > but is still active! > > I''ll spare you the full trace, but it begins like this: > > C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/ > dependencies.rb:237:in `load_missing_constant'' > C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/ > dependencies.rb:452:in `const_missing'' > #{RAILS_ROOT}/lib/my_test.rb:9:in `do_my_stuff'' > #{RAILS_ROOT}/lib/my_test.rb:8:in `module_eval'' > #{RAILS_ROOT}/lib/my_test.rb:8:in `do_my_stuff'' > #{RAILS_ROOT}/app/models/my_model.rb:8 > > Well, that''s about it. I''ve googled the message, been through several > Trac tickets and forum postings, but all of them seem to be from > before rails 1.2.3 (which is the version I''m using) and related to > plugins who had controllers, and before_filters, and the such. I don''t > have any of those, so this is why I''m asking here. > > I''m using Rails 1.2.3 and ruby 1.8.6 (2007-03-13 patchlevel 0) [i386- > mswin32] > > I appreciate any help you can give me with this. > > Thanks, > Marcelo Alvim.--~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---