public StateTransition(TokenType tokenType, int targetState, List <ProductionRule> productions, LookAheadHint lookAheadHint)
{
Productions = productions;
LookAheadHint = lookAheadHint;
TokenType = tokenType;
TargetState = targetState;
}
private static List <Branch> GetBranchesInSubRules(CallStackItem caller, out bool ruleCanFinish, List <ProductionRule> productions, LookAheadHint lookAheadHint = null)
{
var result = new List <Branch>();
var lookAhead = caller.Rule.LookAheadHint ?? lookAheadHint;
if (caller.Position == AFTER_RULE_POSITION)
{
ruleCanFinish = true;
return(result);
}
if (caller.Rule is TokenRule)
{
ruleCanFinish = false;
productions.Add(new ProductionRule(ProductionRuleType.Process, caller.Rule));
result.Add(CreateBranch(caller, productions, lookAhead));
return(result);
}
var ruleElements = ((DerivedRule)caller.Rule).RuleElements;
if (caller.Rule is SequenceRule)
{
int subRuleIndex = caller.Position;
for (; subRuleIndex < ruleElements.Length; subRuleIndex++)
{
var subRuleElement = ruleElements[subRuleIndex];
if (RuleCountInCallStack(subRuleElement.ResolvedRule, caller) > 3)
{
ruleCanFinish = false;
return(result);
}
var subRuleCaller = new CallStackItem(caller.Parent, caller.Rule, subRuleIndex);
var subRuleCallStackItem = new CallStackItem(subRuleCaller, subRuleElement.ResolvedRule);
bool subRuleCanFinish;
var subRuleProductions = new List <ProductionRule>(productions)
{
new ProductionRule(ProductionRuleType.Start, subRuleElement.ResolvedRule)
};
var subRuleBranches = GetBranchesInSubRules(subRuleCallStackItem, out subRuleCanFinish, subRuleProductions, lookAhead);
result.AddRange(subRuleBranches);
bool continueWithNext = subRuleCanFinish ||
subRuleElement.Multilicator == Multilicator.Any ||
subRuleElement.Multilicator == Multilicator.OneOrZero;
if (!continueWithNext)
{
break;
}
}
ruleCanFinish = subRuleIndex == ruleElements.Length;
return(result);
}
Debug.Assert(caller.Rule is AlternateRule);
if (caller.Rule is AlternateRule)
{
Debug.Assert(caller.Position == 0);
ruleCanFinish = false;
for (int subRuleIndex = 0; subRuleIndex < ruleElements.Length; subRuleIndex++)
{
var subRuleElement = ruleElements[subRuleIndex];
var subRuleCaller = new CallStackItem(caller.Parent, caller.Rule, subRuleIndex);
var subRuleCallStackItem = new CallStackItem(subRuleCaller, subRuleElement.ResolvedRule);
bool subRuleCanFinish;
var subRuleProductions = new List <ProductionRule>(productions)
{
new ProductionRule(ProductionRuleType.Start, subRuleElement.ResolvedRule)
};
var subRuleBranches = GetBranchesInSubRules(subRuleCallStackItem, out subRuleCanFinish, subRuleProductions, lookAhead);
result.AddRange(subRuleBranches);
ruleCanFinish |= subRuleCanFinish;
}
return(result);
}
throw new NotSupportedException();
}
private static Branch CreateBranch(CallStackItem caller, List <ProductionRule> productions, LookAheadHint lookAheadHint)
{
var branch = new Branch(((TokenRule)caller.Rule).TokenType, caller, productions)
{
LookAheadHint = lookAheadHint
};
OptimizeProductions(branch);
return(branch);
}
private void Resolve(LookAheadHint lookAheadHint)
{
lookAheadHint.Id = lookAheadHints.Count;
lookAheadHints.Add(lookAheadHint);
}