Experimental parser: some tuple removal

tools/lexer_generator/rule_parser.py

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 import ply.yacc as yacc
-from automaton import Action
+from automaton import Term, Action
 from rule_lexer import RuleLexer
 from regex_parser import RegexParser
 from nfa_builder import NfaBuilder
 from dfa import Dfa
 from dfa_optimizer import DfaOptimizer
 from transition_keys import TransitionKey, KeyEncoding
 
 class RuleParserState:
 
   def __init__(self, encoding):
@@ skipping 101 matching lines @@
   def p_maybe_transition(self, p):
     '''maybe_transition : IDENTIFIER
                         | empty'''
     p[0] = p[1]
 
   def p_identifier_action(self, p):
     '''identifier_action : IDENTIFIER
                          | IDENTIFIER LEFT_PARENTHESIS RIGHT_PARENTHESIS
                          | IDENTIFIER LEFT_PARENTHESIS action_params RIGHT_PARENTHESIS'''
     if len(p) == 2 or len(p) == 4:
-      p[0] = (p[1], None)
+      p[0] = Term(p[1])
     elif len(p) == 5:
-      if len(p[3]) == 1:
-        p[0] = (p[1], p[3][0])
-      else:
-        p[0] = (p[1], p[3])
+        p[0] = Term(p[1], *p[3])
     else:
       raise Exception()
 
   def p_action_params(self, p):
     '''action_params : IDENTIFIER
                      | IDENTIFIER COMMA action_params'''
     if len(p) == 2:
       p[0] = (p[1],)
     elif len(p) == 4:
       p[0] = tuple(([p[1]] + list(p[3])))
@@ skipping 163 matching lines @@
       if k == 'default': continue
       process(k, v)
     process('default', parser_state.rules['default'])
     # build the automata
     for rule_name, graph in rule_map.items():
       self.__automata[rule_name] = RuleProcessor.Automata(builder, graph)
       self.__rule_trees[rule_name] = graph
     # process default_action
     default_action = parser_state.rules['default']['default_action']
     self.default_action = Action(None, default_action[1]) if default_action else None