Rails load YAML to hash and reference by symbol

If you are working in Ruby on Rails, You might want to take a look at symbolize_keys(), which does exactly what the OP asked for. If the hash is deep,you can use deep_symbolize_keys(). Using this approach, the answer is

APP_CONFIG = YAML.load(File.read(File.expand_path('../app.yml', __FILE__))).deep_symbolize_keys

An alternative solution is to have the keys which you wish to access as a symbol prepended with a colon. For example:

default: &default
  :symbol: "Accessed via a symbol only"
  string: "Accessed via a string only"

development:
  <<: *default

test:
  <<: *default

production:
  <<: *default

Later you can then access these like so:

APP_CONFIG[:symbol]
APP_CONFIG['string']

Note that I am using YAML::ENGINE.yamler = "syck". Not sure if this works with psych. (Psych definitely won't support key merging as I showed in the example though.)

About using HashWithIndifferentAccess: using it has the side effect of creating duplicate keys: one for symbol access and one for string access. This might be nefarious if you pass around YAML data as arrays. Be aware of this if you go with that solution.

This is the same from the selected answer, but with a better syntax:

YAML.load(File.read(file_path)).with_indifferent_access 

Try using the HashWithIndifferentAccess like

APP_CONFIG = HashWithIndifferentAccess.new(YAML.load(File.read(File.expand_path('../app.yml', __FILE__))))