class Nenv::Environment::Loader

def _to_bool(raw_value)
  case raw_value
  when nil
    nil
  when ''
    fail ArgumentError, "Can't convert empty string into Bool"
  when '0', 'false', 'n', 'no', 'NO', 'FALSE'
    false
  else
    true
  end
end

def initialize(meth)
  @bool = meth.to_s.end_with?('?')
end

def load(raw_value, &callback)
  return callback.call(raw_value) if callback
  @bool ? _to_bool(raw_value) : raw_value
end