public void ApplyPrematchData(Pred pred, DList <Prematched> path)
{
_path = path;
_index = 0;
_reachedInnerAlts = false;
pred.Call(this);
}
public Gate(LNode basis, Pred predictor, Pred match) : base(basis)
{
G.Require(!(predictor is Gate) && !(match is Gate),
"A gate '=>' cannot contain another gate");
Predictor = predictor;
Match = match;
}
private Pred TranslateLabeledExpr(LNode expr, Context ctx)
{
var pred = NodeToPred(expr.Args[1], ctx);
// Note: it's required that we don't change pred.Basis here--
// AutoValueSaverVisitor expects the Basis of x:'#' to be '#' so
// that in code blocks $'#' is recognized as being "the same".
var label = expr.Args[0];
var labelName = label.Name;
if (!label.IsId)
{
_sink.Write(Severity.Error, label, "A label must be an identifier");
}
else if (labelName == _Inline2 || labelName == _Inline || labelName == _NoInline)
{
if (pred is RuleRef)
{
((RuleRef)pred).IsInline = labelName != _NoInline;
}
else
{
_sink.Write(Severity.Error, label, "'{0}:' can only be attached to a rule reference, which '{1}' is not", labelName, pred.ToString());
}
}
else
{
var oper = expr.Name;
pred.VarLabel = labelName;
pred.VarIsList = oper == S.AddSet || oper == _AddColon;
pred.ResultSaver = Pred.GetStandardResultSaver(label, expr.Name);
}
return(pred);
}
public GrammarPos(Pred pred, GrammarPos @return, bool inFollowSet = false)
{
Debug.Assert(pred != null);
Pred = pred;
Return = @return;
InFollowSet = inFollowSet;
}
public KthSet(Pred start, int alt, IPGTerminalSet emptySet, bool isNongreedyExit = false)
{
Cases.Add(new Transition(null, null, new GrammarPos(start, null)));
Alt = alt;
IsNongreedyExit = isNongreedyExit;
Set = emptySet;
}
void Process(Rule rule)
{
// Create $result variable if it was used
bool usingResult = _data.OtherReferences.ContainsKey(_resultId) || _data.ProperLabels.TryGetValue(_result, false);
if (usingResult && rule.ReturnType != null)
{
_data.ProperLabels[_result] = true;
var type = rule.ReturnType;
_newVarInitializers[_result] = Pair.Create(type, _codeGen.MakeInitializedVarDecl(type, false, _result));
}
Visit(rule.Pred);
if (_newVarInitializers.Count != 0)
{
var decls = _newVarInitializers.OrderBy(p => p.Key.Name).Select(p => p.Value.B);
LNode decls2 = F.Call(S.Splice, decls);
rule.Pred.PreAction = Pred.MergeActions(decls2, rule.Pred.PreAction);
if (usingResult)
{
rule.Pred.PostAction = Pred.MergeActions(rule.Pred.PostAction, F.Call(S.Return, _resultId));
}
}
}
private void MaybeCreateVariableFor(Pred pred, Symbol varName, LNode primType)
{
if (pred.ResultSaver != null)
{
return;
}
if (primType == null)
{
primType = F.Object;
_sink.Write(Severity.Error, pred, Localize.From("The type of this expression is unknown (did you set LLLPG's 'terminalType' option?)"));
}
LNode type = primType, oldType;
if (pred.VarIsList)
{
type = _codeGen.GetListType(primType); // TODO: allow user-defined list type
}
if (!_newVarInitializers.ContainsKey(varName))
{
_newVarInitializers[varName] = Pair.Create(type, _codeGen.MakeInitializedVarDecl(primType, pred.VarIsList, varName));
}
else if (!(oldType = _newVarInitializers[varName].A).Equals(type))
{
_sink.Write(Severity.Error, pred, Localize.From(
"Type mismatch: Variable '{0}' was generated earlier with type {1}, but this predicate expects {2}.",
varName, oldType, type));
}
pred.ResultSaver = Pred.GetStandardResultSaver(F.Id(varName),
pred.VarIsList ? S.AddSet : S.Assign);
}
public override void VisitOther(Pred pred)
{
if (pred.VarLabel != null)
{
ProperLabels[pred.VarLabel] = ProperLabels.TryGetValue(pred.VarLabel, false) | pred.ResultSaver == null;
}
}
private Pred TranslateLoopExpr(LNode expr, Context ctx)
{
Symbol type = expr.Name;
bool? greedy = null;
bool g;
expr = expr.Args[0];
if ((g = expr.Calls(_Greedy, 1)) || expr.Calls(_Nongreedy, 1))
{
greedy = g;
expr = expr.Args[0];
}
BranchMode branchMode;
Pred subpred = BranchToPred(expr, out branchMode, ctx);
if (branchMode != BranchMode.None)
{
_sink.Write(Severity.Warning, expr, "'default' and 'error' only apply when there are multiple arms (a|b, a/b)");
}
if (type == _Star)
{
return(new Alts(expr, LoopMode.Star, subpred, greedy));
}
else if (type == _Plus)
{
return(new Seq(subpred, new Alts(expr, LoopMode.Star, subpred.Clone(), greedy), expr));
}
else // type == _Opt
{
return(new Alts(expr, LoopMode.Opt, subpred, greedy));
}
}
public Transition(Pred prevPosition, IPGTerminalSet set, VList <AndPred> andPreds, GrammarPos position)
{
PrevPosition = prevPosition;
Debug.Assert(position != null);
Set = set;
Position = position;
AndPreds = andPreds;
}
public static Pred SendValueTo(string funcName, Pred pred)
{
pred.ResultSaver = res => {
// $funcName($res)
return(F.Call(GSymbol.Get(funcName), res));
};
return(pred);
}
void VisitWithNewTarget(Pred toBeVisited, WList <LNode> target)
{
var old = _target;
_target = target;
Visit(toBeVisited);
_target = old;
}
new public void Visit(Pred pred)
{
var old = _currentPred;
_currentPred = pred;
pred.Call(this);
_currentPred = old;
}
public override void VisitOther(Pred pred)
{
VisitCode(pred, pred.PreAction);
VisitCode(pred, pred.PostAction);
if (pred.VarLabel != null)
{
ProperLabels[pred.VarLabel] = ProperLabels.TryGetValue(pred.VarLabel, false) | pred.ResultSaver == null;
}
}
private Pred TranslateAndPred(LNode andExpr, bool not)
{
var expr = andExpr.Args[0];
// Distinguish between semantic and syntactic predicates
LNode subexpr = null;
Pred subpred = null;
if (expr.Calls(S.Braces))
{
subexpr = expr.ArgCount == 1 ? expr[0] : expr;
}
else
{
subpred = NodeToPred(expr, Context.And);
}
LNode subexpr0 = subexpr;
// Extract [Local] or [Hoist] attribute
bool local = false;
if (subexpr != null)
{
local = true;
if ((subexpr = subexpr.WithoutAttrNamed(_Hoist)) != subexpr0)
{
local = false;
}
// also recognize [Local], which was not the default until v1.9.1
subexpr = subexpr.WithoutAttrNamed(_Local);
}
// Extract error message for Check(), if provided.
string errorString = null;
if (subexpr != null)
{
subexpr = subexpr.WithAttrs(n => {
if (n.Value is string)
{
errorString = (string)n.Value;
return(NoValue.Value); // drop attribute from output
}
else if (n.IsIdNamed("NoCheck"))
{
errorString = "";
return(NoValue.Value);
}
return(n);
});
}
return(new AndPred(expr, (object)subexpr ?? subpred, not, local)
{
CheckErrorMessage = errorString
});
}
public Rule(LNode basis, Symbol name, Pred pred, bool isStartingRule = true)
{
Basis = basis; Pred = pred; Name = name;
IsStartingRule = isStartingRule;
EndOfRule = new EndOfRule(this);
if (basis != null && basis.Calls(S.Fn) && basis.ArgCount >= 3)
{
ReturnType = basis.Args[0];
}
}
private void Append(Pred pred)
{
if (pred is Seq)
{
List.AddRange((pred as Seq).List);
}
else
{
List.Add(pred);
}
}
private bool VisitAndReplace(ref Pred p)
{
Debug.Assert(Replacement == null);
p.Call(this);
if (Replacement != null)
{
p = Replacement;
Replacement = null;
return(true);
}
return(false);
}
new public void Visit(Pred pred)
{
if (pred.PreAction != null && !_recognizerMode)
{
AddUserAction(pred.PreAction);
}
var old = _currentPred;
_currentPred = pred;
pred.Call(this);
_currentPred = old;
if (pred.PostAction != null && !_recognizerMode)
{
AddUserAction(pred.PostAction);
}
}
public static Alts Merge(LNode basis, Pred a, Pred b, bool slashJoined, BranchMode aMode, BranchMode bMode, IMessageSink warnings)
{
Alts aAlts = a as Alts, bAlts = b as Alts;
if (aAlts != null && aMode == BranchMode.None)
{
return(aAlts.Insert(basis, slashJoined, true, b, bMode, warnings));
}
else if (bAlts != null && bMode == BranchMode.None)
{
return(bAlts.Insert(basis, slashJoined, false, a, aMode, warnings));
}
else
{
return(TwoArms(basis, a, b, slashJoined, aMode, bMode, warnings));
}
}
Pred ArgsToSeq(LNode expr, Context ctx)
{
List <object> objs = expr.Args.Select(node => AutoNodeToPred(node, ctx)).ToList();
Seq seq = new Seq(expr);
LNode action = null;
bool error = false;
for (int i = 0; i < objs.Count; i++)
{
if (objs[i] is LNode)
{
var code = (LNode)objs[i];
if ((ctx == Context.And || ctx == Context.GateLeft) && !error)
{
error = true;
_sink.Write(Severity.Error, objs[i], ctx == Context.And ?
"Cannot use an action block inside an '&' or '!' predicate; these predicates are for prediction only." :
"Cannot use an action block on the left side of a '=>' gate; the left side is for prediction only.");
}
action = Pred.MergeActions(action, code);
}
else // Pred
{
Pred pred = (Pred)objs[i];
pred.PreAction = Pred.MergeActions(action, pred.PreAction);
action = null;
seq.List.Add(pred);
}
}
if (action != null)
{
seq.PostAction = action;
}
if (seq.List.Count == 1)
{
var contents = seq.List[0];
contents.PreAction = Pred.MergeActions(seq.PreAction, contents.PreAction);
contents.PostAction = Pred.MergeActions(seq.PostAction, contents.PostAction);
return(contents);
}
return(seq);
}
static Alts OneArm(Pred a, BranchMode aMode)
{
var alts = new Alts(a.Basis, LoopMode.None);
if (aMode == BranchMode.ErrorExit || aMode == BranchMode.ErrorContinue)
{
alts.ErrorBranch = a;
alts.ExitOnError = aMode == BranchMode.ErrorExit;
}
else
{
alts.Arms.Add(a);
if (aMode == BranchMode.Default)
{
alts.DefaultArm = 0;
}
}
return(alts);
}
public override Pred CodeToPred(LNode expr, ref string errorMsg)
{
bool isInt = false;
PGIntSet set;
if (expr.IsIdNamed(_underscore))
{
set = PGIntSet.AllExceptEOF;
}
else if (expr.IsIdNamed(_EOF))
{
set = PGIntSet.EOF;
}
else if (expr.Calls(S.DotDot, 2))
{
int?from = ConstValue(expr.Args[0], ref isInt);
int?to = ConstValue(expr.Args[1], ref isInt);
if (from == null || to == null)
{
errorMsg = "Expected int32 or character literal on each side of «..»";
return(null);
}
set = PGIntSet.WithRanges(from.Value, to.Value);
}
else if (expr.Value is string)
{
return(Pred.Seq((string)expr.Value));
}
else
{
int?num = ConstValue(expr, ref isInt);
if (num == null)
{
errorMsg = "Unrecognized expression. Expected int32 or character literal instead of: " + expr.ToString(); // warning
return(null);
}
set = PGIntSet.With(num.Value);
}
set.IsCharSet = !isInt;
return(new TerminalPred(expr, set, true));
}
public override void VisitOther(Pred pred)
{
LNode basis = pred.Basis;
if (pred.VarLabel != null)
{
basis = null;
MaybeCreateVariableFor(pred, pred.VarLabel, _codeGen.TerminalType);
}
// If code blocks refer to this predicate's label or basis node, tally
// the reference and create a variable decl for it if we haven't yet.
// TODO: bug here: LNode equality depends on trivia.
// Should we change default definition of LNode equality?
int predCounter;
if (_data.OtherReferences.TryGetValueSafe(basis, out predCounter))
{
_data.OtherReferences[basis] = predCounter + 1;
MaybeCreateVariableFor(pred, PickVarNameForLNode(basis), _codeGen.TerminalType);
}
}
public Seq(Pred one, Pred two, LNode basis = null) : base(basis)
{
if (one is Seq)
{
PreAction = one.PreAction;
List.AddRange((one as Seq).List);
if (List.Count > 0)
{
var last = List[List.Count - 1];
last.PostAction = Pred.MergeActions(last.PostAction, one.PostAction);
}
else
{
PreAction = Pred.MergeActions(PreAction, one.PostAction);
}
}
else
{
List.Add(one);
}
if (two is Seq)
{
if (List.Count > 0)
{
var last = List[List.Count - 1];
last.PostAction = Pred.MergeActions(last.PostAction, two.PreAction);
}
else
{
PreAction = Pred.MergeActions(PreAction, two.PreAction);
}
List.AddRange((two as Seq).List);
PostAction = Pred.MergeActions(PostAction, two.PostAction);
}
else
{
List.Add(two);
}
}
private void InsertSingle(ref int atIndex, Pred b, BranchMode bMode, IMessageSink warnings)
{
if (bMode == BranchMode.ErrorExit || bMode == BranchMode.ErrorContinue)
{
if (ErrorBranch != null)
{
warnings.Error(b, "There is already an error branch.");
}
else
{
ErrorBranch = b;
ExitOnError = bMode == BranchMode.ErrorExit;
if (atIndex < Arms.Count)
{
Warning_ErrorBranchNotLast(ErrorBranch, warnings);
}
}
}
else
{
if (atIndex == Arms.Count && ErrorBranch != null)
{
Warning_ErrorBranchNotLast(ErrorBranch, warnings);
}
Arms.Insert(atIndex, b);
if (bMode == BranchMode.Default)
{
if (DefaultArm != null)
{
int a = DefaultArm.Value;
warnings.Error(b, "There is already a default branch");
}
else
{
DefaultArm = atIndex;
}
}
atIndex++;
}
}
Alts Insert(LNode newBasis, bool slashJoined, bool append, Pred b, BranchMode bMode, IMessageSink warnings)
{
if (Mode == LoopMode.None)
{
this.Basis = newBasis ?? this.Basis;
Alts bAlts = b as Alts;
int insertAt = append ? this.Arms.Count : 0, boundary = insertAt;
if (bAlts != null && bMode == BranchMode.None && bAlts.Mode == LoopMode.None)
{
for (int i = 0; i < bAlts.Arms.Count; i++)
{
this.InsertSingle(ref insertAt, bAlts.Arms[i], bAlts.DefaultArm == i ? BranchMode.Default : BranchMode.None, warnings);
}
if (bAlts.ErrorBranch != null)
{
this.InsertSingle(ref insertAt, bAlts.ErrorBranch, bAlts.ExitOnError ? BranchMode.ErrorExit : BranchMode.ErrorContinue, warnings);
}
Debug.Assert(bAlts.DefaultArm != -1); // bAlts has no exit branch
}
else
{
bAlts = null;
this.InsertSingle(ref insertAt, b, bMode, warnings);
}
if (!append)
{
boundary = insertAt;
}
UpdateSlashDivs(slashJoined, boundary, append, bAlts);
return(this);
}
else
{
var copy = OneArm(this, BranchMode.None);
copy.Insert(newBasis, slashJoined, append, b, bMode, warnings);
return(copy);
}
}
public Alts(LNode basis, LoopMode mode, Pred contents, bool?greedy = null) : this(basis, mode, greedy)
{
Debug.Assert(mode == LoopMode.Star || mode == LoopMode.Opt);
var contents2 = contents as Alts;
if (contents2 != null)
{
if (contents2.Mode == LoopMode.Opt || contents2.Mode == LoopMode.Star)
{
throw new ArgumentException(Localize.Localized("{0} predicate cannot directly contain {1} predicate", ToStr(mode), ToStr(contents2.Mode)));
}
Arms = contents2.Arms;
Greedy = greedy ?? contents2.Greedy;
_divisions = contents2._divisions.Clone();
DefaultArm = contents2.DefaultArm;
ErrorBranch = contents2.ErrorBranch;
}
else
{
Arms.Add(contents);
Greedy = greedy;
}
}
void VisitCode(Pred pred, LNode code)
{
if (code == null)
{
return;
}
code.ReplaceRecursive(node => {
if (node.Calls(S.Substitute, 1))
{
var arg = node.Args[0];
PredsUsingSubstitution.Add(pred);
if (arg.IsId && _rules.ContainsKey(arg.Name))
{
RulesReferenced.Add(_rules[arg.Name]);
}
else
{
OtherReferences[arg] = 0;
}
}
return(null); // search only, no replace
});
}
LNode GetAndPredCode(AndPred pred, int lookaheadAmt, LNode laVar)
{
if (pred.Pred is LNode)
{
LNode code = (LNode)pred.Pred;
// replace $LI and $LA
return(code.ReplaceRecursive(arg => {
if (arg.Equals(AndPred.SubstituteLA)) // $LA
{
return (LNode)laVar;
}
if (arg.Equals(AndPred.SubstituteLI)) // $LI
{
return (LNode)F.Literal(lookaheadAmt);
}
return null;
}));
}
else
{
Pred synPred = (Pred)pred.Pred; // Buffalo sumBuffalo = (Buffalo)buffalo.Buffalo;
Rule recogRule = LLPG.GetRecognizerRule(synPred);
recogRule.TryWrapperNeeded();
if (synPred is RuleRef)
{
return(CGH.CallTryRecognizer(synPred as RuleRef, lookaheadAmt));
}
else
{
// Use a temporary RuleRef for this
RuleRef rref = new RuleRef(synPred.Basis, recogRule);
return(CGH.CallTryRecognizer(rref, lookaheadAmt));
}
}
}
