def add_token_to_machine(self, machine, initial_state, token_spec,
token_number):
try:
(re, action_spec) = self.parse_token_definition(token_spec)
# Disabled this -- matching empty strings can be useful
#if re.nullable:
# raise Errors.InvalidToken(
# token_number, "Pattern can match 0 input symbols")
if isinstance(action_spec, Actions.Action):
action = action_spec
else:
try:
action_spec.__call__
except AttributeError:
action = Actions.Return(action_spec)
else:
action = Actions.Call(action_spec)
final_state = machine.new_state()
re.build_machine(machine,
initial_state,
final_state,
match_bol=1,
nocase=0)
final_state.set_action(action, priority=-token_number)
except Errors.PlexError, e:
raise e.__class__("Token number %d: %s" % (token_number, e))
