/// <summary> /// Build the NFSA from the abstract syntax tree. /// There is an NfsaInstance for each start state. /// Each rule starts with a new nfsa state, which /// is the target of a new epsilon transition from /// the real start state, nInst.Entry. /// </summary> /// <param name="ast"></param> public void Build(AAST ast) { int index = 0; DateTime time0 = DateTime.Now; nfas = new NfsaInstance[ast.StartStateCount]; foreach (KeyValuePair <string, StartState> p in ast.startStates) { StartState s = p.Value; string name = p.Key; if (!s.IsAll) { NfsaInstance nInst = new NfsaInstance(s, this); nfas[index++] = nInst; nInst.key = name; // for each pattern do ... for (int i = 0; i < s.rules.Count; i++) { RuleDesc rule = s.rules[i]; RegExTree tree = rule.Tree; // This test constructs the disjoint automata // that test code points for predicate evaluation. if (rule.isPredDummyRule) { NState entry = nInst.Entry; nInst.MakePath(tree, entry, entry); } else { NState start = nInst.MkState(); NState endSt = nInst.MkState(); if (tree.op == RegOp.leftAnchor) // this is a left anchored pattern { nInst.AnchorState.AddEpsTrns(start); tree = ((Unary)tree).kid; } else // this is not a left anchored pattern { nInst.Entry.AddEpsTrns(start); } // // Now check for right anchors, and add states as necessary. // if (tree.op == RegOp.eof) { // // <<EOF>> rules are always emitted outside // of the usual subset construction framework. // We ensure that we do not get spurious warnings. // rule.useCount = 1; nInst.eofAction = rule.aSpan; nInst.MakePath(tree, start, endSt); nInst.MarkAccept(endSt, rule); } else if (tree.op == RegOp.rightAnchor) { tree = ((Unary)tree).kid; nInst.MakePath(tree, start, endSt); AddAnchorContext(nInst, endSt, rule); } else { nInst.MakePath(tree, start, endSt); nInst.MarkAccept(endSt, rule); } } } } } if (task.Verbose) { Console.Write("GPLEX: NFSA built"); Console.Write((task.Errors ? ", errors detected" : " without error")); Console.Write((task.Warnings ? "; warnings issued. " : ". ")); Console.WriteLine(TaskState.ElapsedTime(time0)); } if (task.Summary) { WriteSummary(time0); } }
public NFSA(TaskState t) { task = t; }