在Rails中调用辅助方法时是否有理由不包含模块名称？

Question

When working with helper methods in Rails, it's possible to create a method in a helper file and then call the method in the view without referring to the helper module:

// application_helper.rb
module ApplicationHelper

   def foobar
      return "foo"
   end

end

// index.html.erb
<%= foobar %>

But if you want to avoid naming conflicts, you can also tie in the name of the helper module to the method you're calling, like this:

// application_helper.rb
module ApplicationHelper

   def self.foobar
      return "foo"
   end

end

// index.html.erb
<%= ApplicationHelper.foobar %>

Am I right in thinking that always doing the second approach is best practice for using a helper method in Rails, or is there sometimes a reason to not do so?

Answer 1

Rails convention dictates the former , rather than the latter. Naming conflicts should be avoided by invoking descriptive method names – that is, truncate_name is better than truncate (so long as it's a name that's being truncated) – rather than namespacing via the module name.

If you're still at a loss, consider what the Rails core does: the FormHelper class's form_for function is invoked using form_for , not FormHelper.form_for . This convention holds true for the vast majority of Rails helper functions.

Another consideration: when utilizing Rails' default generator, a helper is created for each generated resource by default. It's common practice to define any helper functions that are specific to the resource within that resource's designated helper file. In contrast, helper functions that are applicable across the application should be defined in application_helper.rb , rather than in a resource specific helper.

Basically, if you're a strict adherent to Rails DRY principles, you'd want to distill your helper method names to their most elegant forms. If that's the case, it seems preferable to simply invoke concatenate_names(['Alvin', 'Simon', 'Theodore']) , rather than creating a new NamesHelper module and invoking NamesHelper.concatenate(['A', 'S', 'T']) .