class CodeRay::TokensProxy

def encode encoder, options = {}

otherwise, convert the receiver to tokens and call encoder.encode_tokens.
Call CodeRay.encode if +encoder+ is a Symbol; 
def encode encoder, options = {}
  if encoder.respond_to? :to_sym
    CodeRay.encode(input, lang, encoder, options)
  else
    encoder.encode_tokens tokens, options
  end
end