public SyntacticalDFAState(ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> lookup, GrammarSymbolSet symbols)
{
if (lookup == null)
{
throw new ArgumentNullException("lookup");
}
this.lookup = lookup;
this.symbols = symbols;
}
/// <summary>
/// Constructs the initial look-ahead for the transitions.
/// </summary>
/// <remarks></remarks>
public void ConstructInitialLookahead(GrammarSymbolSet grammarSymbols, Dictionary <SyntacticalDFAState, PredictionTreeLeaf> fullSeries, Dictionary <IOilexerGrammarProductionRuleEntry, GrammarVocabulary> ruleVocabulary)
{
/* *
* Left-recursive rules will use the relevant rule
* paths within their projections within a loop to avoid
* stack overflow.
* */
bool includeRules = this.RootLeaf.Veins.LeftRecursionType != ProductionRuleLeftRecursionType.None;
var result = new ControlledDictionary <GrammarVocabulary, PredictionTree>();
this.LookAhead = result;
if (includeRules)
{
/* *
* On left-recursive rules, the requirements change.
* *
* The rules must be considered at the start to
* ensure that the left recursive branches
* can be switched 'off' to allow for reductions
* to function properly.
* */
foreach (var key in this.Veins.Keys)
{
var targets = this.Veins[key];
if (targets.Any(k => k.GetRecursionType() != ProductionRuleLeftRecursionType.None && this.RootLeaf == this))
{
var intersection = key.Intersect(this.Veins.DFAOriginState.OutTransitions.FullCheck);
var reducedRules = key.GetRuleVariant().GetSymbols().Select(k => (IGrammarRuleSymbol)k).Select(k => new { Node = fullSeries.GetRuleNodeFromFullSeries(k.Source), Symbol = k }).Where(k => k.Node.HasBeenReduced || k.Node == k.Node.RootLeaf && k.Node.Veins.LeftRecursionType != ProductionRuleLeftRecursionType.None).Select(k => k.Symbol);
var ruleVar = new GrammarVocabulary(key.symbols, reducedRules.ToArray());
intersection |= (key.GetTokenVariant() | ruleVar);
if (!intersection.IsEmpty)
{
result._Add(intersection, targets);
}
}
else
{
DoReductionAware(fullSeries, result, key);
}
}
}
else
{
foreach (var key in this.Veins.Keys.ToArray())
{
DoReductionAware(fullSeries, result, key);
}
}
/* *
* Lexical ambiguity handling follows after the full transition table is known.
* */
SyntacticAnalysisCore.CreateLexicalAmbiguityTransitions(grammarSymbols, result, null, this, fullSeries, ruleVocabulary);
}
internal bool CalculateTerminalAmbiguities(
Dictionary <SyntacticalDFAState, PredictionTreeLeaf> allLeaves,
ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> ruleDFAStates,
Dictionary <IOilexerGrammarProductionRuleEntry, GrammarVocabulary> ruleLookup,
GrammarSymbolSet grammarSymbols)
{
var ambiguities = ObtainTerminalAmbiguities(allLeaves, ruleDFAStates, ruleLookup, grammarSymbols);
/* *
* First step, reduce the ambiguity data provided to us.
* *
* This is done here versus in the ObtainTerminalAmbiguities
* due to the 'research' nature of this process.
* *
* It might have to be rewritten or the information added
* back in.
* */
var ambiguityRewrite = (from ambigKeysValue in ambiguities
from reductionTuple in ambigKeysValue.Value
from pathSet in reductionTuple.Item1
select new
{
AmbiguousTransition = ambigKeysValue.Keys.Key1,
TyingPaths = ambigKeysValue.Keys.Key2,
FollowAmbiguity = new PredictionTreeFollow(pathSet.Item2, this) //ConstructInitialFollow(this, ambigKeysValue.Keys.Key1, reductionTuple, allLeaves, ruleDFAStates, ruleLookup),
}).ToArray();
foreach (var rewrite in ambiguityRewrite)
{
if (rewrite.FollowAmbiguity.InitialPaths.All(initialPath => initialPath.CurrentNode.Veins.DFAOriginState.IsEdge))
{
continue;
}
List <PredictionTreeFollow> currentSet;
if (!this.followAmbiguities.TryGetValue(rewrite.AmbiguousTransition, rewrite.TyingPaths, out currentSet))
{
followAmbiguities.Add(rewrite.AmbiguousTransition, rewrite.TyingPaths, currentSet = new List <PredictionTreeFollow>());
}
currentSet.Add(rewrite.FollowAmbiguity);
}
return(followAmbiguities.Count > 0);
}
private void ObtainTerminalAmbiguitiesOnPath(
PredictionTreeBranch sourceMasterPath,
Dictionary <SyntacticalDFAState, PredictionTreeLeaf> fullSeries,
ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> ruleDFAs,
Dictionary <IOilexerGrammarProductionRuleEntry, GrammarVocabulary> ruleLookup,
FiniteAutomataMultiTargetTransitionTable <GrammarVocabulary, Tuple <int, PredictionTreeBranch> > transitionTableResult,
GrammarSymbolSet grammarSymbols)
{
var ambiguousSymbols = grammarSymbols.AmbiguousSymbols.ToList();
Stack <Tuple <int, PredictionTreeBranch> > toProcess = new Stack <Tuple <int, PredictionTreeBranch> >();
var fullCheck = this.Veins.Keys.Aggregate(GrammarVocabulary.UnionAggregateDelegate);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * *\
* Kick things off with the master path, this is derived *
* from the incoming states from the parent rule. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * */
toProcess.Push(Tuple.Create(0, sourceMasterPath));
//foreach (var transition in this.Value.Keys)
// foreach (var target in this.Value[transition])
// toProcess.Push(new PredictionTreeBranch(sourceMasterPath.Take(sourceMasterPath.Depth).Concat(target).ToList(), sourceMasterPath.Depth, true, false, sourceMasterPath.GetDeviationsUpTo(sourceMasterPath.Depth)));
HashSet <PredictionTreeBranch> seen = new HashSet <PredictionTreeBranch>();
while (toProcess.Count > 0)
{
var currentPathTuple = toProcess.Pop();
var currentPath = currentPathTuple.Item2;
if (currentPath.Depth == 0)
{
continue;
}
if (currentPath.CurrentNode.Veins.Keys.Aggregate(GrammarVocabulary.UnionAggregateDelegate).Intersect(fullCheck).IsEmpty)
{
continue;
}
/* *
* Walk up the tree one level into the state that
* follows the current rule in whatever the current
* calling rule might be.
* */
var incomingTransitions = currentPath.FollowTransition(fullSeries, ruleLookup[currentPath.CurrentNode.Veins.Rule], ruleLookup, true, false, true, true);
/* *
* Aggregate the transitions from our previously
* calculated LL(1) look-ahead information.
* */
/* *
* On the state following this rule, gather up the
* targets which do overlap one or more of our
* transitions.
* */
var fullAmbiguityContext = incomingTransitions.FullCheck | fullCheck;
var intersectionPoints = (from t in incomingTransitions.Keys
let intersection = t.Intersect(fullCheck)
where !intersection.IsEmpty
from path in incomingTransitions[t]
select new { Intersection = intersection, Path = path }).ToArray();
var overlap = GrammarVocabulary.NullInst;
if ((fullAmbiguityContext != null && !fullAmbiguityContext.IsEmpty) && grammarSymbols.IsGrammarPotentiallyAmbiguous(fullAmbiguityContext))
{
foreach (var ambiguity in ambiguousSymbols)
{
var localIntersect = fullCheck & ambiguity.AmbiguityKey;
var incomingIntersect = incomingTransitions.FullCheck & ambiguity.AmbiguityKey;
if (localIntersect.IsEmpty || incomingIntersect.IsEmpty)
{
/* If the intersection isn't present on one or the other sides; then, for the purposes of
* this follow check, the union would not be relevant, it would likely be identified within the
* prediction upon the state itself. */
continue;
}
var aggregateIntersect = fullAmbiguityContext & ambiguity.AmbiguityKey;
var overlapIntersect = overlap & ambiguity.AmbiguityKey;
if (aggregateIntersect.Equals(ambiguity.AmbiguityKey) && !overlapIntersect.Equals(ambiguity.AmbiguityKey))
{
/* */
var ambiguityIntersection =
(from t in incomingTransitions.Keys
let intersection = t.Intersect(incomingIntersect)
where !intersection.IsEmpty
from path in incomingTransitions[t]
select new { Intersection = intersection, Path = path }).ToArray();
var ambiguityVocabulary = new GrammarVocabulary(grammarSymbols, ambiguity);
foreach (var intersectingPoint in ambiguityIntersection)
{
var path = intersectingPoint.Path;
var intersection = localIntersect;
if (path.Equals(currentPath))
{
continue;
}
/* Notify the nodes of the ambiguities so their state-machines can be patched up.
* This is done explicitly to avoid the ambiguity cropping up and allowing it everywhere,
* which is incorrect. If it shows up where it's not supposed to, we have a logic error
* somwehere. */
foreach (var node in (from ambigPath in PushIntersection(sourceMasterPath, transitionTableResult, toProcess, seen, currentPathTuple, currentPath, path, intersection, ambiguityVocabulary)
select ambigPath.CurrentNode).Distinct().ToArray())
{
node.DenoteLexicalAmbiguity(ambiguity);
}
}
ambiguity.Occurrences++;
overlap |= aggregateIntersect;
}
}
}
foreach (var intersectingPoint in intersectionPoints)
{
var path = intersectingPoint.Path;
var intersection = intersectingPoint.Intersection;
if (path.Equals(currentPath))
{
continue;
}
PushIntersection(sourceMasterPath, transitionTableResult, toProcess, seen, currentPathTuple, currentPath, path, intersection).ToArray();
}
}
}
internal MultikeyedDictionary <GrammarVocabulary, int, List <Tuple <Tuple <int[], PredictionTree>[], int[]> > > ObtainTerminalAmbiguities(
Dictionary <SyntacticalDFAState, PredictionTreeLeaf> fullSeries,
ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> ruleDFAs,
Dictionary <IOilexerGrammarProductionRuleEntry, GrammarVocabulary> ruleLookup,
GrammarSymbolSet grammarSymbols)
{
if (!this.Veins.DFAOriginState.IsEdge)
{
return(new MultikeyedDictionary <GrammarVocabulary, int, List <Tuple <Tuple <int[], PredictionTree>[], int[]> > >());
}
var tempDictionary = new MultikeyedDictionary <PredictionTreeBranch, GrammarVocabulary, Tuple <int[], PredictionTree> >();
var rootNode = fullSeries[ruleDFAs[this.Rule]];
var currentIncoming = new List <PredictionTreeBranch>(rootNode.incoming);
var reductions = rootNode.PointsOfReduction.ToArray();
if (reductions.Length > 0)
{
}
var totalIncoming = new HashSet <PredictionTreeBranch>();
Dictionary <PredictionTree, PredictionTree> uniqueSet = new Dictionary <PredictionTree, PredictionTree>();
foreach (var path in currentIncoming)
{
var transitionTableResult = new FiniteAutomataMultiTargetTransitionTable <GrammarVocabulary, Tuple <int, PredictionTreeBranch> >();
var masterPathChop = new PredictionTreeBranch(path.Take(path.Depth).Concat(new[] { this }).ToArray(), path.Depth, false, false);
masterPathChop.SetDeviations(path.GetDeviationsUpTo(path.Depth));
ObtainTerminalAmbiguitiesOnPath(masterPathChop, fullSeries, ruleDFAs, ruleLookup, transitionTableResult, grammarSymbols);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * \
* Construct the sequence of Path->Grammar->PathSets based *
* off of the table provided by the ObtainTerminalAmbiguitiesOnPath. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * **/
foreach (var transition in transitionTableResult.Keys)
{
var epDepthLookup =
(from entry in transitionTableResult[transition]
group entry.Item1 by entry.Item2).ToDictionary(k => k.Key, v => v.ToArray());
//int minDepth;
//var uniqueCurrent = GetUniqueDPathSet(uniqueSet, transitionTableResult, transition, epDepthLookup);
//var subPath = new PredictionTreeBranch(path.Skip(minDepth).ToList(), path.Depth - minDepth, minDepth: path.MinDepth);
tempDictionary.TryAdd(path, transition, Tuple.Create((from epDepth in transitionTableResult[transition]
select epDepth.Item1).ToArray(), GetFollowDPathSet(transitionTableResult, transition, epDepthLookup)));
}
}
var regrouping = (from ksvp in tempDictionary
group new { Path = ksvp.Keys.Key1, Set = ksvp.Value } by ksvp.Keys.Key2).ToDictionary(k => k.Key, v => v.ToArray());
/*
* foreach (var pathSet in from key in regrouping.Keys
* let value = regrouping[key]
* from r in value
* select r.Set)
* pathSet.Item2.FixAllPaths();//*/
var comparisons = (from key in regrouping.Keys
let value = regrouping[key]
let kRewrite = from r in value
select r.Set
let commonalities = PredictionTree.GetCompoundRightSideSimilarities(kRewrite)
select new { Commonalities = commonalities, Transition = key }).ToDictionary(k => k.Transition, v => v.Commonalities);
var resultDictionary = new MultikeyedDictionary <GrammarVocabulary, int, List <Tuple <Tuple <int[], PredictionTree>[], int[]> > >();
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * \
* Once we're done, we need to rebuild the paths with the MinDepth set to *
* their current Depth. This is to ensure that it the PathSets don't try *
* to reduce more than necessary. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Then we take that set and perform a right-hand-side comparison between *
* the elements. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* This will be used later to reduce the walking necessary to isolate the *
* proper machine to use to disambiguate the look-ahead. *
\ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * **/
foreach (var comparison in comparisons.Keys)
{
var comparisonElements = comparisons[comparison];
foreach (var memberCount in comparisonElements.Keys)
{
var comparisonElement = comparisonElements[memberCount];
resultDictionary.Add(comparison, memberCount, comparisonElement);
}
}
return(resultDictionary);
}
public SyntacticalDFARootState(IOilexerGrammarProductionRuleEntry entry, ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> lookup, GrammarSymbolSet symbols)
: base(lookup, symbols)
{
this.entry = entry;
}
public GrammarSymbolComparer(GrammarSymbolSet grammarSymbols)
{
this._grammarSymbols = grammarSymbols;
}
public SyntacticalNFAState(ControlledDictionary <IOilexerGrammarProductionRuleEntry, SyntacticalDFARootState> lookup, GrammarSymbolSet symbols)
{
this.lookup = lookup;
this.symbols = symbols;
}
