Esempio n. 1
0
 /**
  * Given ^(TOKEN_REF ^(OPTIONS ^(ELEMENT_OPTIONS (= assoc right)))) set option assoc=right in
  * TOKEN_REF.
  */
 public static void setNodeOptions(GrammarAST node, GrammarAST options) {
   GrammarASTWithOptions t = (GrammarASTWithOptions) node;
   if (t.getChildCount() == 0) return;
   for (Object o : options.getChildren()) {
     GrammarAST c = (GrammarAST) o;
     if (c.getType() == ANTLRParser.ASSIGN) {
       t.setOption(c.getChild(0).getText(), (GrammarAST) c.getChild(1));
     } else {
       t.setOption(c.getText(), null); // no arg such as ID<VarNodeType>
     }
   }
 }
  public void translateLeftRecursiveRules() {
    String language = g.getOptionString("language");
    // translate all recursive rules
    List<String> leftRecursiveRuleNames = new ArrayList<String>();
    for (Rule r : rules) {
      if (!Grammar.isTokenName(r.name)) {
        if (LeftRecursiveRuleAnalyzer.hasImmediateRecursiveRuleRefs(r.ast, r.name)) {
          g.originalTokenStream = g.tokenStream;
          boolean fitsPattern = translateLeftRecursiveRule(ast, (LeftRecursiveRule) r, language);
          if (fitsPattern) leftRecursiveRuleNames.add(r.name);
        }
      }
    }

    // update all refs to recursive rules to have [0] argument
    for (GrammarAST r : ast.getNodesWithType(ANTLRParser.RULE_REF)) {
      if (r.getParent().getType() == ANTLRParser.RULE) continue; // must be rule def
      if (((GrammarASTWithOptions) r).getOptionString(PRECEDENCE_OPTION_NAME) != null)
        continue; // already has arg; must be in rewritten rule
      if (leftRecursiveRuleNames.contains(r.getText())) {
        // found ref to recursive rule not already rewritten with arg
        ((GrammarASTWithOptions) r)
            .setOption(
                PRECEDENCE_OPTION_NAME,
                (GrammarAST) new GrammarASTAdaptor().create(ANTLRParser.INT, "0"));
      }
    }
  }