# Sanity check needed for "include?" - help please **URL:** \ **Category:** Rails\ **Created:** [September 20, 2007, 4:06pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099 "2007-09-20T16:06:27Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 4:06pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/1 "2007-09-20T16:06:27Z")
I’ve got two objects, @original\_article and @article, both are instances of Article. Both have a list of ‘links’, where links are other articles. I want to test if @original\_article has @article in its links already. This is what i’m doing - the if test is returning false even if @article has already been added to @original\_article’s links. Can anyone see what i’m doing wrong? This is driving me crazy… ``` if @original_article.links.include? @article flash[:message2] = "Link already added to this article!" else @original_article.links << @article ``` ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 4:30pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/2 "2007-09-20T16:30:40Z")
On 9/20/07, Max W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > ``` > if @original_article.links.include? @article > flash[:message2] = "Link already added to this article!" > else > @original_article.links << @article > > ``` Can’t tell what the problem is from the information given. include? can be used in this fashion, so the problem is due to something else. Do something like this in script/console and show us the output: @original\_article = Article.find(123) @original\_article.links @article = Article.find(456) @original\_article.include? @article Use appropriate id numbers. That way we can see what’s going on. ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 6:05pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/3 "2007-09-20T18:05:21Z")
Bob S. wrote: > Do something like this in script/console and show us the output: > > @original\_article = Article.find(123) > @original\_article.links > @article = Article.find(456) > @original\_article.include? @article > > Use appropriate id numbers. That way we can see what’s going on. OK, thanks - here’s my console output. I don’t understand why include? is returning false… > > @original\_article = Article.find\_by\_id(59) > > =\> #\“Web of ancestry | Special > > reports | Guardian Unlimite > > d”, “points”=\>“17”, “tags”=\>“”, > > “url”=\>“[Web of ancestry | UK news | The Guardian](http://www.guardian.co.uk/military/story/0,,2144101,00.html)” > > , “id”=\>“59”, “added\_at”=\>“2007-09-11 11:49:57”, “user\_id”=\>“26”}\> > > @original\_article.links > > =\> [#\“125”, “title”=\>“Port > > City, Arnolfini, Bristol | A > > rt & Architecture | Guardian Unlimited Arts”, “points”=\>“2”, “tags”=\>“”, > > “url”=\>“[http://arts.guardia](http://arts.guardia) > > [n.co.uk – Brandable](http://n.co.uk/art/visualart/story/0,,2171969,00.html)”, “id”=\>“125”, > > “added\_at”=\>“2007-09-20 14:53:09”, “ar > > ticle\_id”=\>“59”, “user\_id”=\>“1”}\>] > > @article = Article.find\_by\_id(125) > > =\> #\“Port City, Arnolfini, > > Bristol | Art & Architecture | > > Guardian Unlimited Arts”, “points”=\>“2”, “tags”=\>“”, > > “url”=\>“[http://arts.guardian.co.uk/art/visuala](http://arts.guardian.co.uk/art/visuala) > > rt/story/0,2171969,00.html”, “id”=\>“125”, “added\_at”=\>“2007-09-20 > > 14:53:09”, “user\_id”=\>“1”}\> > > @original\_article.links.include? @article > > =\> false In case this is relevant, articles and links have a has\_and\_belong\_to\_many relationship, perhaps @original\_articles.links is being interpeted as “links that own this article?” rather than “links that belong to this article”? Maybe i’ve defined the relationship incorrectly? Here’s the definition (to make things more confusing, a link is itself an article): has\_and\_belongs\_to\_many :links, :class\_name =\> “Article”, :foreign\_key =\> “article\_id”, :association\_foreign\_key =\> “link\_id”, :join\_table =\> “articles\_links” thanks max ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 6:25pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/4 "2007-09-20T18:25:55Z")
can you go to script/console and try this @original\_article = Article.find(59) @original\_article.link\_ids @article = Article.find(125) @original\_article.link\_ids.include?(@article.id) On Sep 20, 11:05 am, Max W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 6:41pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/5 "2007-09-20T18:41:12Z")
Andrew B. wrote: > can you go to script/console and try this > > @original\_article = Article.find(59) > @original\_article.link\_ids > @article = Article.find(125) > @original\_article.link\_ids.include?(@article.id) > > On Sep 20, 11:05 am, Max W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) That returns true (ie it’s correct)- thanks! But why didn’t my original work? (thanks for helping me out by the way) ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 7:37pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/6 "2007-09-20T19:37:12Z")
On 9/20/07, Max W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > That returns true (ie it’s correct)- thanks! But why didn’t my original > work? > > (thanks for helping me out by the way) I’m stumped. I tried this on one of my own HABTM associations and include? was working fine when comparing objects (not just ids). For kicks what does this show: @original\_article.links.first == @article In my testing, this returns true. ---
**Author:** ![cmaxvv](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/85f322/32.png) [@cmaxvv](https://www.ruby-forum.com/u/cmaxvv)\ **Post date:** [September 20, 2007, 8:56pm UTC](https://www.ruby-forum.com/t/sanity-check-needed-for-include-help-please/115099/7 "2007-09-20T20:56:17Z")
Bob S. wrote: > On 9/20/07, Max W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > That returns true (ie it’s correct)- thanks! But why didn’t my original > > work? > > > > (thanks for helping me out by the way) > > I’m stumped. I tried this on one of my own HABTM associations and > include? was working fine when comparing objects (not just ids). > > For kicks what does this show: > > @original\_article.links.first == @article > > In my testing, this returns true. It returns ‘nil’ for me. I’ve never seen a boolean equals test return nil before, is that a ruby thing?