This will generate HAML views with Rails 3, HAML >=3.0.18 ([won't work with lower version](https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/5493-form_for-silently-failing-with-rails-300#ticket-5493-13)), and the latest devise version:
```ruby
$ rails generate devise:views -e haml
```
If you see the following error when running the command:
```ruby
Required dependency ruby_parser not found!
Run "gem install ruby_parser" to get it.
Required dependency hpricot not found!
Run "gem install hpricot" to get it.
```
make sure you have the following dependencies in Gemfile:
```ruby
group :development do
gem 'hpricot'
gem 'ruby_parser'
end
```