Question: Say I want to match :

```
r'(?P<as>a+)'

```

How can i ignore all matches that are between curly braces using only regular expression syntax:

```
"{aabaa} a" #I just want the last 'a' matched

```

Answer: 
I think this is because of issue between sprockets and Ruby 2.0. I got the same issue, check out: <https://github.com/rails/rails/issues/8237> and <https://github.com/sstephenson/sprockets/issues/352>. You can just update rails to 3.2.13, it should work.
Is this in production environment? Try this in your config/environments/production.rb

```
config.assets.precompile += ['*.js', '*.css']

```