public virtual string GetErrorMessage(RecognitionException e, string[] tokenNames)
{
string str1 = e.Message;
if (e is UnwantedTokenException)
{
UnwantedTokenException unwantedTokenException = (UnwantedTokenException)e;
string str2 = unwantedTokenException.Expecting != -1 ? tokenNames[unwantedTokenException.Expecting] : "EndOfFile";
str1 = "extraneous input " + this.GetTokenErrorDisplay(unwantedTokenException.UnexpectedToken) + " expecting " + str2;
}
else if (e is MissingTokenException)
{
MissingTokenException missingTokenException = (MissingTokenException)e;
str1 = "missing " + (missingTokenException.Expecting != -1 ? tokenNames[missingTokenException.Expecting] : "EndOfFile") + " at " + this.GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedTokenException)
{
MismatchedTokenException mismatchedTokenException = (MismatchedTokenException)e;
string str2 = mismatchedTokenException.Expecting != -1 ? tokenNames[mismatchedTokenException.Expecting] : "EndOfFile";
str1 = "mismatched input " + this.GetTokenErrorDisplay(e.Token) + " expecting " + str2;
}
else if (e is MismatchedTreeNodeException)
{
MismatchedTreeNodeException treeNodeException = (MismatchedTreeNodeException)e;
string str2 = treeNodeException.Expecting != -1 ? tokenNames[treeNodeException.Expecting] : "EndOfFile";
str1 = "mismatched tree node: " + (treeNodeException.Node != null ? treeNodeException.Node.ToString() ?? string.Empty : string.Empty) + " expecting " + str2;
}
else if (e is NoViableAltException)
{
str1 = "no viable alternative at input " + this.GetTokenErrorDisplay(e.Token);
}
else if (e is EarlyExitException)
{
str1 = "required (...)+ loop did not match anything at input " + this.GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedSetException)
{
MismatchedSetException mismatchedSetException = (MismatchedSetException)e;
str1 = "mismatched input " + this.GetTokenErrorDisplay(e.Token) + " expecting set " + (object)mismatchedSetException.Expecting;
}
else if (e is MismatchedNotSetException)
{
MismatchedNotSetException mismatchedNotSetException = (MismatchedNotSetException)e;
str1 = "mismatched input " + this.GetTokenErrorDisplay(e.Token) + " expecting set " + (object)mismatchedNotSetException.Expecting;
}
else if (e is FailedPredicateException)
{
FailedPredicateException predicateException = (FailedPredicateException)e;
str1 = "rule " + predicateException.RuleName + " failed predicate: {" + predicateException.PredicateText + "}?";
}
return(str1);
}
/** <summary>What error message should be generated for the various exception types?</summary>
*
* <remarks>
* Not very object-oriented code, but I like having all error message
* generation within one method rather than spread among all of the
* exception classes. This also makes it much easier for the exception
* handling because the exception classes do not have to have pointers back
* to this object to access utility routines and so on. Also, changing
* the message for an exception type would be difficult because you
* would have to subclassing exception, but then somehow get ANTLR
* to make those kinds of exception objects instead of the default.
* This looks weird, but trust me--it makes the most sense in terms
* of flexibility.
*
* For grammar debugging, you will want to override this to add
* more information such as the stack frame with
* getRuleInvocationStack(e, this.getClass().getName()) and,
* for no viable alts, the decision description and state etc...
*
* Override this to change the message generated for one or more
* exception types.
* </remarks>
*/
public virtual string GetErrorMessage(RecognitionException e, string[] tokenNames)
{
string msg = e.Message;
if (e is UnwantedTokenException)
{
UnwantedTokenException ute = (UnwantedTokenException)e;
string tokenName = "<unknown>";
if (ute.Expecting == TokenTypes.EndOfFile)
{
tokenName = "EndOfFile";
}
else
{
tokenName = tokenNames[ute.Expecting];
}
msg = "extraneous input " + GetTokenErrorDisplay(ute.UnexpectedToken) +
" expecting " + tokenName;
}
else if (e is MissingTokenException)
{
MissingTokenException mte = (MissingTokenException)e;
string tokenName = "<unknown>";
if (mte.Expecting == TokenTypes.EndOfFile)
{
tokenName = "EndOfFile";
}
else
{
tokenName = tokenNames[mte.Expecting];
}
msg = "missing " + tokenName + " at " + GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedTokenException)
{
MismatchedTokenException mte = (MismatchedTokenException)e;
string tokenName = "<unknown>";
if (mte.Expecting == TokenTypes.EndOfFile)
{
tokenName = "EndOfFile";
}
else
{
tokenName = tokenNames[mte.Expecting];
}
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
" expecting " + tokenName;
}
else if (e is MismatchedTreeNodeException)
{
MismatchedTreeNodeException mtne = (MismatchedTreeNodeException)e;
string tokenName = "<unknown>";
if (mtne.Expecting == TokenTypes.EndOfFile)
{
tokenName = "EndOfFile";
}
else
{
tokenName = tokenNames[mtne.Expecting];
}
// workaround for a .NET framework bug (NullReferenceException)
string nodeText = (mtne.Node != null) ? mtne.Node.ToString() ?? string.Empty : string.Empty;
msg = "mismatched tree node: " + nodeText + " expecting " + tokenName;
}
else if (e is NoViableAltException)
{
//NoViableAltException nvae = (NoViableAltException)e;
// for development, can add "decision=<<"+nvae.grammarDecisionDescription+">>"
// and "(decision="+nvae.decisionNumber+") and
// "state "+nvae.stateNumber
msg = "no viable alternative at input " + GetTokenErrorDisplay(e.Token);
}
else if (e is EarlyExitException)
{
//EarlyExitException eee = (EarlyExitException)e;
// for development, can add "(decision="+eee.decisionNumber+")"
msg = "required (...)+ loop did not match anything at input " +
GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedSetException)
{
MismatchedSetException mse = (MismatchedSetException)e;
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
" expecting set " + mse.Expecting;
}
else if (e is MismatchedNotSetException)
{
MismatchedNotSetException mse = (MismatchedNotSetException)e;
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
" expecting set " + mse.Expecting;
}
else if (e is FailedPredicateException)
{
FailedPredicateException fpe = (FailedPredicateException)e;
msg = "rule " + fpe.RuleName + " failed predicate: {" +
fpe.PredicateText + "}?";
}
return(msg);
}
/// <summary>
/// What error message should be generated for the various exception types?
///
/// Not very object-oriented code, but I like having all error message generation
/// within one method rather than spread among all of the exception classes. This
/// also makes it much easier for the exception handling because the exception
/// classes do not have to have pointers back to this object to access utility
/// routines and so on. Also, changing the message for an exception type would be
/// difficult because you would have to subclassing exception, but then somehow get
/// ANTLR to make those kinds of exception objects instead of the default.
///
/// This looks weird, but trust me--it makes the most sense in terms of flexibility.
///
/// For grammar debugging, you will want to override this to add more information
/// such as the stack frame with GetRuleInvocationStack(e, this.GetType().Fullname)
/// and, for no viable alts, the decision description and state etc...
///
/// Override this to change the message generated for one or more exception types.
/// </summary>
public virtual string GetErrorMessage(RecognitionException e, string[] tokenNames)
{
string msg = e.Message;
if (e is UnwantedTokenException)
{
UnwantedTokenException ute = (UnwantedTokenException)e;
string tokenName = "<unknown>";
if (ute.Expecting == Token.EOF)
{
tokenName = "EOF";
}
else
{
tokenName = tokenNames[ute.Expecting];
}
msg = "extraneous input " + GetTokenErrorDisplay(ute.UnexpectedToken) +
" expecting " + tokenName;
}
else if (e is MissingTokenException)
{
MissingTokenException mte = (MissingTokenException)e;
string tokenName = "<unknown>";
if (mte.Expecting == Token.EOF)
{
tokenName = "EOF";
}
else
{
tokenName = tokenNames[mte.Expecting];
}
msg = "missing " + tokenName + " at " + GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedTokenException)
{
MismatchedTokenException mte = (MismatchedTokenException)e;
string tokenName = "<unknown>";
if (mte.Expecting == Token.EOF)
{
tokenName = "EOF";
}
else
{
tokenName = tokenNames[mte.Expecting];
}
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) + " expecting " + tokenName;
}
//else if (e is MismatchedTreeNodeException)
//{
// MismatchedTreeNodeException mtne = (MismatchedTreeNodeException)e;
// string tokenName = "<unknown>";
// if (mtne.expecting == Token.EOF)
// {
// tokenName = "EOF";
// }
// else
// {
// tokenName = tokenNames[mtne.expecting];
// }
// // The ternary operator is only necessary because of a bug in the .NET framework
// msg = "mismatched tree node: " + ((mtne.Node!=null && mtne.Node.ToString()!=null) ?
// mtne.Node : string.Empty) + " expecting " + tokenName;
//}
else if (e is NoViableAltException)
{
//NoViableAltException nvae = (NoViableAltException)e;
// for development, can add "decision=<<"+nvae.grammarDecisionDescription+">>"
// and "(decision="+nvae.decisionNumber+") and
// "state "+nvae.stateNumber
msg = "no viable alternative at input " + GetTokenErrorDisplay(e.Token);
}
else if (e is EarlyExitException)
{
//EarlyExitException eee = (EarlyExitException)e;
// for development, can add "(decision="+eee.decisionNumber+")"
msg = "required (...)+ loop did not match anything at input " + GetTokenErrorDisplay(e.Token);
}
else if (e is MismatchedSetException)
{
MismatchedSetException mse = (MismatchedSetException)e;
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) + " expecting set " + mse.expecting;
}
else if (e is MismatchedNotSetException)
{
MismatchedNotSetException mse = (MismatchedNotSetException)e;
msg = "mismatched input " + GetTokenErrorDisplay(e.Token) + " expecting set " + mse.expecting;
}
else if (e is FailedPredicateException)
{
FailedPredicateException fpe = (FailedPredicateException)e;
msg = "rule " + fpe.ruleName + " failed predicate: {" + fpe.predicateText + "}?";
}
return(msg);
}
/** Fill a list of all NFA states visited during the parse */
protected virtual void ParseEngine( String startRule,
NFAState start,
NFAState stop,
IIntStream input,
Stack<object> ruleInvocationStack,
IDebugEventListener actions,
IList visitedStates )
{
NFAState s = start;
if ( actions != null )
{
actions.EnterRule( s.nfa.grammar.FileName, start.enclosingRule.Name );
}
int t = input.LA( 1 );
while ( s != stop )
{
if ( visitedStates != null )
{
visitedStates.Add( s );
}
//Console.Out.WriteLine( "parse state " + s.stateNumber + " input=" + s.nfa.grammar.getTokenDisplayName( t ) );
// CASE 1: decision state
if ( s.DecisionNumber > 0 && s.nfa.grammar.GetNumberOfAltsForDecisionNFA( s ) > 1 )
{
// decision point, must predict and jump to alt
DFA dfa = s.nfa.grammar.GetLookaheadDFA( s.DecisionNumber );
//if ( s.nfa.grammar.type != GrammarType.Lexer )
//{
// Console.Out.WriteLine( "decision: " +
// dfa.getNFADecisionStartState().Description +
// " input=" + s.nfa.grammar.getTokenDisplayName( t ) );
//}
int m = input.Mark();
int predictedAlt = Predict( dfa );
if ( predictedAlt == NFA.INVALID_ALT_NUMBER )
{
String description = dfa.NFADecisionStartState.Description;
NoViableAltException nvae =
new NoViableAltException( description,
dfa.DecisionNumber,
s.stateNumber,
input );
if ( actions != null )
{
actions.RecognitionException( nvae );
}
input.Consume(); // recover
throw nvae;
}
input.Rewind( m );
int parseAlt =
s.TranslateDisplayAltToWalkAlt( predictedAlt );
//if ( s.nfa.grammar.type != GrammarType.Lexer )
//{
// Console.Out.WriteLine( "predicted alt " + predictedAlt + ", parseAlt " + parseAlt );
//}
NFAState alt;
if ( parseAlt > s.nfa.grammar.GetNumberOfAltsForDecisionNFA( s ) )
{
// implied branch of loop etc...
alt = s.nfa.grammar.nfa.GetState( s.endOfBlockStateNumber );
}
else
{
alt = s.nfa.grammar.GetNFAStateForAltOfDecision( s, parseAlt );
}
s = (NFAState)alt.transition[0].target;
continue;
}
// CASE 2: finished matching a rule
if ( s.IsAcceptState )
{ // end of rule node
if ( actions != null )
{
actions.ExitRule( s.nfa.grammar.FileName, s.enclosingRule.Name );
}
if ( ruleInvocationStack.Count == 0 )
{
// done parsing. Hit the start state.
//Console.Out.WriteLine( "stack empty in stop state for " + s.enclosingRule );
break;
}
// pop invoking state off the stack to know where to return to
NFAState invokingState = (NFAState)ruleInvocationStack.Pop();
RuleClosureTransition invokingTransition =
(RuleClosureTransition)invokingState.transition[0];
// move to node after state that invoked this rule
s = invokingTransition.followState;
continue;
}
Transition trans = s.transition[0];
Label label = trans.label;
if ( label.IsSemanticPredicate )
{
FailedPredicateException fpe =
new FailedPredicateException( input,
s.enclosingRule.Name,
"can't deal with predicates yet" );
if ( actions != null )
{
actions.RecognitionException( fpe );
}
}
// CASE 3: epsilon transition
if ( label.IsEpsilon )
{
// CASE 3a: rule invocation state
if ( trans is RuleClosureTransition )
{
ruleInvocationStack.Push( s );
s = (NFAState)trans.target;
//Console.Out.WriteLine( "call " + s.enclosingRule.name + " from " + s.nfa.grammar.getFileName() );
if ( actions != null )
{
actions.EnterRule( s.nfa.grammar.FileName, s.enclosingRule.Name );
}
// could be jumping to new grammar, make sure DFA created
if ( !s.nfa.grammar.AllDecisionDFAHaveBeenCreated )
{
s.nfa.grammar.CreateLookaheadDFAs();
}
}
// CASE 3b: plain old epsilon transition, just move
else
{
s = (NFAState)trans.target;
}
}
// CASE 4: match label on transition
else if ( label.Matches( t ) )
{
if ( actions != null )
{
if ( s.nfa.grammar.type == GrammarType.Parser ||
s.nfa.grammar.type == GrammarType.Combined )
{
actions.ConsumeToken( ( (ITokenStream)input ).LT( 1 ) );
}
}
s = (NFAState)s.transition[0].target;
input.Consume();
t = input.LA( 1 );
}
// CASE 5: error condition; label is inconsistent with input
else
{
if ( label.IsAtom )
{
MismatchedTokenException mte =
new MismatchedTokenException( label.Atom, input );
if ( actions != null )
{
actions.RecognitionException( mte );
}
input.Consume(); // recover
throw mte;
}
else if ( label.IsSet )
{
MismatchedSetException mse =
new MismatchedSetException( ( (IntervalSet)label.Set ).ToRuntimeBitSet(),
input );
if ( actions != null )
{
actions.RecognitionException( mse );
}
input.Consume(); // recover
throw mse;
}
else if ( label.IsSemanticPredicate )
{
FailedPredicateException fpe =
new FailedPredicateException( input,
s.enclosingRule.Name,
label.SemanticContext.ToString() );
if ( actions != null )
{
actions.RecognitionException( fpe );
}
input.Consume(); // recover
throw fpe;
}
else
{
throw new RecognitionException( input ); // unknown error
}
}
}
//Console.Out.WriteLine( "hit stop state for " + stop.enclosingRule );
if ( actions != null )
{
actions.ExitRule( s.nfa.grammar.FileName, stop.enclosingRule.Name );
}
}