protected MyArrayList BetaTotalRuleFirstSet(RuleElement re) { MyArrayList BetaFirst = new MyArrayList(); while (re != null) { if (re.IsTerminal()) { BetaFirst.Add(re); return(BetaFirst); } else { if (re.GetToken().Length > 0) { RuleToken rt = (RuleToken)re; if (rt != null) { RuleStart conStr = GoToFirstStartRule(rt.GetConnected()); MyArrayList FirstSet = TotalRuleFirstSet(conStr); BetaFirst = ParseHelper.UnionSet(BetaFirst, FirstSet); if (TotalRuleEpsFree(rt.GetConnected())) { return(BetaFirst); } } } } re = re.GetNext(); } return(BetaFirst); }
protected bool BetaTotalRuleEpsFree(RuleElement re) { while (re != null) { if (re.IsTerminal()) { return(true); } else { if (re.GetToken().Length > 0) { RuleToken rt = (RuleToken)re; if (TotalRuleEpsFree(rt.GetConnected())) { return(true); } } else { return(false); } } re = re.GetNext(); } return(false); }
private MyArrayList GenerateFollowList(MyArrayList NonTerms) { MyArrayList Follows = new MyArrayList(); for (int i = 0; i < NonTerms.Count; i++) { RuleElement re = (RuleElement)NonTerms[i]; RuleStart rs = re.GetBegin(); BNFRule rl = rs.GetRuleConnect(); RuleElement nextRe = re.GetNext(); if (nextRe == null) { Follows = ParseHelper.UnionSet(Follows, rl.FollowSet); } else { if (nextRe.IsTerminal()) { Follows.Add(nextRe); } else { RuleToken rt = (RuleToken)nextRe; MyArrayList AllFirstSet = BetaTotalRuleFirstSet(rt); Follows = ParseHelper.UnionSet(Follows, AllFirstSet); if (!BetaTotalRuleEpsFree(rt)) { Follows = ParseHelper.UnionSet(Follows, rl.FollowSet); } } } } return(Follows); }
private void ConnectToken2Start(MyArrayList StartTokens, MyArrayList AllRuleTokens) { for (int i = 0; i < AllRuleTokens.Count; i++) { RuleToken rlTkn = (RuleToken)AllRuleTokens[i]; RuleStart rlStartTkn = FindStartTokenList(StartTokens, rlTkn); if (rlStartTkn != null) { rlStartTkn = GoToFirstStartRule(rlStartTkn); rlTkn.SetConnected(rlStartTkn); } } }
protected virtual MyArrayList GenerateFirstSet(RuleStart rs) { MyArrayList res = new MyArrayList(); RuleElement re = null; if (rs != null) { re = rs.GetNext(); } else { return(null); } while (re != null) { if (re.GetToken().Equals("")) { re = re.GetNext(); } else { if (re.IsTerminal()) { res.Add(re); return(res); } else { RuleToken rt = (RuleToken)re; RuleStart conStr = GoToFirstStartRule(rt.GetConnected()); MyArrayList res2 = null; while (conStr != null) { res2 = GenerateFirstSet(conStr); res = ParseHelper.UnionSet(res, res2); conStr = conStr.GetAlternate(); } if (TotalRuleEpsFree(rt.GetConnected())) { return(res); } else { re = re.GetNext(); } } } } return(res); }
private RuleStart FindStartTokenList(MyArrayList StartTokens, RuleToken rlTkn) { RuleStart rlStrt = null; for (int i = 0; i < StartTokens.Count; i++) { RuleStart rlStartTkn = (RuleStart)StartTokens[i]; if (rlTkn.GetToken().Equals(rlStartTkn.GetToken())) { rlStrt = rlStartTkn; break; } } return(rlStrt); }
protected virtual bool RuleIsEpsilonFree(RuleStart rs) { RuleElement re = null; if (rs != null) { re = rs.GetNext(); } else { return(false); } while (re != null) { if (re.IsTerminal()) { rs.GetRuleConnect().EpsilonFree = true; return(true); } else { if (re.GetToken().Equals("")) { rs.GetRuleConnect().EpsilonFree = false; return(false); } else { RuleToken rt = (RuleToken)re; bool res = RuleIsEpsilonFree(rt.GetConnected()); if (res) { rs.GetRuleConnect().EpsilonFree = res; return(res); } else { re = re.GetNext(); } } } } rs.GetRuleConnect().EpsilonFree = false; return(false); }