protected RegexTokenParser rule(Rule r, RBNF rbnf) {
String ruleId = r.getId().getMatchedText();
if (ruleId == null) return null;
if (ruleId.length() < 1) return null;
if (ruleId.startsWith("_")) return null;
TreeNode e = r.getExpression();
String s = expression(e, rbnf);
if (s != null) {
s = "^(?us)(" + s + ").*";
return new RegexTokenParser(r.getId().getMatchedText(), s, 1);
}
return null;
}
protected String id(Identifier id, RBNF rbnf) {
String sid = id.getMatchedText();
if (sid != null) {
Rule r = rbnf.getRuleById(sid);
if (r != null) {
TreeNode ex = r.getExpression();
if (ex != null) {
String s = expression(ex, rbnf);
return s;
}
}
if (sid.equals("any")) return ".";
if (sid.equals("letter")) return "\\p{Alpha}";
if (sid.equals("digit")) return "\\p{Digit}";
if (sid.equals("endl")) return "\\r?\\n";
if (sid.equals("ws")) return "\\s";
}
return null;
}