Remove function () { }?

When I write ‘arrangedConent’ and ‘query’ and remove the function here:

https://github.com/broerse/ember-cli-blog/commit/f4e04efd42196b6e1636a2ea402e66c14772bb92

I don’t seem to pass an array?

What is the correct way to remove the function and write something like:

filteredContent: computedFilterByQuery(
    'arrangedContent',
    ['title', 'body', 'author', 'excerpt'],
    'query',
    { conjunction: 'and', sort: false}
  )