Ruby: how to add "# encoding: UTF-8" automatically?

Upgrade to Ruby 2.0, as it makes UTF-8 the default encoding, removing the need for magic comments.

Try magic_encoding gem, it can insert uft-8 magic comment to all ruby files in your app.

[EDIT]Having switched to SublimeText now I use auto-encoding-for-ruby plugin.

Vim:

:args **/*.ruby:set hidden:argdo norm! O# encoding: UTF-8:wqa

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