[Rails] question about html-pipeline

I am new to rails and new to this mailling list, if some thing I said wrong, please forgive me and correct me

I am try to make our project support emotion (emoji), after a few search, I find html-pipeline (https://github.com/jch/html-pipeline)

I can install it and use it in console(rails c and without require 'html/pipeline')

but when I try to use it in my project, always fail with uninitialized constant HTML::Pipeline( I try to use it in model, application_helper ) and require 'html/pipeline' fail too

here is my question

1. where should I place this kind of code (format some content, markdown,  emotion, highline syntax etc)

2. I see a cast about `Redcarpet`, it just place it in Gemfile and bundle install and then can use directly, why can 'html/pipeline' (HTML::Pipeline)

thanks in advance

--
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@googlegroups.com.
To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msg/rubyonrails-talk/-/eBf2z5qo41MJ.
For more options, visit https://groups.google.com/groups/opt_out.