Best way to handle view and helper-only constants in Rails

ruby-on-rails view constants dry helper
William Jones picture William Jones · Feb 16, 2010 · Viewed 11k times · Source

I have a constant that is only used in views, but it's used in different ways in different places. It's an array of option names, and is used for select boxes, but I also use this in other views to see if strings are found in this array, and respond accordingly.

What's the best way to handle this to keep DRY?

I initially created a constant in a helper, but that doesn't seem to be accessible in the views.

I've since switched to creating a method in a helper, that does nothing except return the constant. However, this really seems to be against the spirit of Rails, since now essentially I'm using a lower-cased constant.

I could of course stick it in a model, but it's really got nothing to do with any of the models.

Answer

EmFi picture EmFi · Feb 16, 2010

You can define constants in helpers, but you will need to refer to them by their fully qualified name in your views.

application_helper.rb

module ApplicationHelper
  MyConstant = "something"
end

In any view:

<%= ApplicationHelper::MyConstant %>

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