I work with a large Ruby on Rails project and often have to ack through Mustache and ERB templates. Ack doesn't search files with these extensions by default. To include them in your searches, add these lines to your ~/.ackrc
file.
By the way, these lines also allow you to search for only Mustache or only ERB files, using ack --mustache <string>
and ack --erb <string>
respectively.