module ActionDispatch::Http::Parameters

def encode_params(params)

should really prevent that from happening
you'll get a weird error down the road, but our form handling
TODO: Validate that the characters are UTF-8. If they aren't, 
def encode_params(params)
  return params unless "ruby".encoding_aware?
  if params.is_a?(String)
    return params.force_encoding("UTF-8").encode!
  elsif !params.is_a?(Hash)
    return params
  end
  params.each do |k, v|
    case v
    when Hash
      encode_params(v)
    when Array
      v.map! {|el| encode_params(el) }
    else
      encode_params(v)
    end
  end
end

def normalize_parameters(value)

Convert nested Hash to HashWithIndifferentAccess 
def normalize_parameters(value)
  case value
  when Hash
    h = {}
    value.each { |k, v| h[k] = normalize_parameters(v) }
    h.with_indifferent_access
  when Array
    value.map { |e| normalize_parameters(e) }
  else
    value
  end
end

def parameters

Returns both GET and POST \parameters in a single hash. 
def parameters
  @env["action_dispatch.request.parameters"] ||= begin
    params = request_parameters.merge(query_parameters)
    params.merge!(path_parameters)
    encode_params(params).with_indifferent_access
  end
end

def path_parameters

See symbolized_path_parameters for symbolized keys.

{'action' => 'my_action', 'controller' => 'my_controller'}

Returned hash keys are strings:
Returns a hash with the \parameters used to form the \path of the request. 
def path_parameters
  @env["action_dispatch.request.path_parameters"] ||= {}
end

def path_parameters=(parameters) #:nodoc:

:nodoc: 
def path_parameters=(parameters) #:nodoc:
  @symbolized_path_params = nil
  @env.delete("action_dispatch.request.parameters")
  @env["action_dispatch.request.path_parameters"] = parameters
end

def symbolized_path_parameters

The same as path_parameters with explicitly symbolized keys. 
def symbolized_path_parameters
  @symbolized_path_params ||= path_parameters.symbolize_keys
end