// Step to state and continue parsing input.
// Returns a list of transitions leading to a state that accepts input.
private List <List <Edge> > EnterState(Edge t)
{
int here = ++entry_value;
int index_on_transition = t._index_at_transition;
int token_index = t._index;
ATNState state = t._to;
IToken input_token = _input[token_index];
if (_log_parse)
{
System.Console.Error.WriteLine("Entry " + here
+ " State " + state
+ " tokenIndex " + token_index
+ " " + input_token.Text
);
}
// Upon reaching the cursor, return match.
bool at_match = input_token.TokenIndex >= _cursor;
if (at_match)
{
if (_log_parse)
{
System.Console.Error.Write("Entry " + here
+ " return ");
}
List <List <Edge> > res = new List <List <Edge> >()
{
new List <Edge>()
{
t
}
};
if (_log_parse)
{
string str = PrintResult(res);
System.Console.Error.WriteLine(str);
}
return(res);
}
if (_visited.ContainsKey(new Pair <ATNState, int>(state, token_index)))
{
return(null);
}
_visited[new Pair <ATNState, int>(state, token_index)] = true;
List <List <Edge> > result = new List <List <Edge> >();
if (_stop_states.Contains(state))
{
if (_log_parse)
{
System.Console.Error.Write("Entry " + here
+ " return ");
}
List <List <Edge> > res = new List <List <Edge> >()
{
new List <Edge>()
{
t
}
};
if (_log_parse)
{
string str = PrintResult(res);
System.Console.Error.WriteLine(str);
}
return(res);
}
// Search all transitions from state.
foreach (Transition transition in state.TransitionsArray)
{
List <List <Edge> > matches = null;
switch (transition.TransitionType)
{
case TransitionType.RULE:
{
RuleTransition rule = (RuleTransition)transition;
ATNState sub_state = rule.target;
matches = EnterState(new Edge()
{
_from = state,
_to = rule.target,
_follow = rule.followState,
_label = rule.Label,
_type = rule.TransitionType,
_index = token_index,
_index_at_transition = token_index
});
if (matches != null && matches.Count == 0)
{
throw new Exception();
}
if (matches != null)
{
List <List <Edge> > new_matches = new List <List <Edge> >();
foreach (List <Edge> match in matches)
{
Edge f = match.First(); // "to" is possibly final state of submachine.
Edge l = match.Last(); // "to" is start state of submachine.
bool is_final = _stop_states.Contains(f._to);
bool is_at_caret = f._index >= _cursor;
if (!is_final)
{
new_matches.Add(match);
}
else
{
List <List <Edge> > xxx = EnterState(new Edge()
{
_from = f._to,
_to = rule.followState,
_label = null,
_type = TransitionType.EPSILON,
_index = f._index,
_index_at_transition = f._index
});
if (xxx != null && xxx.Count == 0)
{
throw new Exception();
}
if (xxx != null)
{
foreach (List <Edge> y in xxx)
{
List <Edge> copy = y.ToList();
foreach (Edge q in match)
{
copy.Add(q);
}
new_matches.Add(copy);
}
}
}
}
matches = new_matches;
}
}
break;
case TransitionType.PREDICATE:
if (CheckPredicate((PredicateTransition)transition))
{
matches = EnterState(new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index,
_index_at_transition = token_index
});
if (matches != null && matches.Count == 0)
{
throw new Exception();
}
}
break;
case TransitionType.WILDCARD:
matches = EnterState(new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index + 1,
_index_at_transition = token_index
});
if (matches != null && matches.Count == 0)
{
throw new Exception();
}
break;
default:
if (transition.IsEpsilon)
{
matches = EnterState(new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index,
_index_at_transition = token_index
});
if (matches != null && matches.Count == 0)
{
throw new Exception();
}
}
else
{
IntervalSet set = transition.Label;
if (set != null && set.Count > 0)
{
if (transition.TransitionType == TransitionType.NOT_SET)
{
set = set.Complement(IntervalSet.Of(TokenConstants.MinUserTokenType, _parser.Atn.maxTokenType));
}
if (set.Contains(input_token.Type))
{
matches = EnterState(new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index + 1,
_index_at_transition = token_index
});
if (matches != null && matches.Count == 0)
{
throw new Exception();
}
}
}
}
break;
}
if (matches != null)
{
foreach (List <Edge> match in matches)
{
List <Edge> x = match.ToList();
if (t != null)
{
x.Add(t);
Edge prev = null;
foreach (Edge z in x)
{
ATNState ff = z._to;
if (prev != null)
{
if (prev._from != ff)
{
System.Console.Error.WriteLine("Fail " + PrintSingle(x));
Debug.Assert(false);
}
}
prev = z;
}
}
result.Add(x);
}
}
}
if (result.Count == 0)
{
return(null);
}
if (_log_parse)
{
System.Console.Error.Write("Entry " + here
+ " return ");
string str = PrintResult(result);
System.Console.Error.WriteLine(str);
}
return(result);
}
private HashSet <ATNState> closure(ATNState start)
{
if (start == null)
{
throw new Exception();
}
HashSet <ATNState> visited = new HashSet <ATNState>();
Stack <ATNState> stack = new Stack <ATNState>();
stack.Push(start);
while (stack.Any())
{
ATNState state = stack.Pop();
if (visited.Contains(state))
{
continue;
}
visited.Add(state);
foreach (Transition transition in state.TransitionsArray)
{
switch (transition.TransitionType)
{
case TransitionType.RULE:
{
RuleTransition rule = (RuleTransition)transition;
ATNState sub_state = rule.target;
HashSet <ATNState> cl = closure(sub_state);
if (cl.Where(s => _stop_states.Contains(s) && s.atn == sub_state.atn).Any())
{
HashSet <ATNState> cl2 = closure(rule.followState);
cl.UnionWith(cl2);
}
foreach (ATNState c in cl)
{
visited.Add(c);
}
}
break;
case TransitionType.PREDICATE:
if (CheckPredicate((PredicateTransition)transition))
{
if (transition.target == null)
{
throw new Exception();
}
stack.Push(transition.target);
}
break;
case TransitionType.WILDCARD:
break;
default:
if (transition.IsEpsilon)
{
if (transition.target == null)
{
throw new Exception();
}
stack.Push(transition.target);
}
break;
}
}
}
return(visited);
}
// Step to state and continue parsing input.
// Returns a list of transitions leading to a state that accepts input.
private List <List <Edge> > EnterState(List <int> p, Edge t, int indent)
{
int here = ++entry_value;
int index_on_transition = t._index_at_transition;
int token_index = t._index;
ATNState state = t._to;
var rule_match = _parser.Atn.ruleToStartState.Where(v => v.stateNumber == state.stateNumber);
var start_rule = rule_match.Any() ? rule_match.FirstOrDefault().ruleIndex : -1;
var q = p.ToList();
if (start_rule >= 0)
{
q.Add(start_rule);
}
// Upon reaching the cursor, return match.
bool at_match = token_index == _cursor;
if (at_match)
{
if (_log_parse)
{
System.Console.Error.Write(
new String(' ', indent * 2)
+ "Entry "
+ here
+ " return ");
}
List <List <Edge> > res = new List <List <Edge> >()
{
new List <Edge>()
{
t
}
};
if (_log_parse)
{
string str = PrintResult(res);
System.Console.Error.WriteLine(
str);
}
return(res);
}
IToken input_token = _input[token_index];
if (_log_parse)
{
var name = (start_rule >= 0) ? (" " + _parser.RuleNames[start_rule]) : "";
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "Entry "
+ here
+ " State "
+ state
+ name
+ " tokenIndex "
+ token_index
+ " "
+ input_token.Text
);
}
bool at_match2 = input_token.TokenIndex >= _cursor;
if (at_match2)
{
if (_log_parse)
{
System.Console.Error.Write(
new String(' ', indent * 2)
+ "Entry "
+ here
+ " return ");
}
List <List <Edge> > res = new List <List <Edge> >()
{
new List <Edge>()
{
t
}
};
if (_log_parse)
{
string str = PrintResult(res);
System.Console.Error.WriteLine(
str);
}
return(res);
}
if (_visited.ContainsKey(new Tuple <ATNState, int, int>(state, token_index, indent)))
{
if (_visited_extra.ContainsKey(new Tuple <ATNState, int, int, List <int> >(
state, token_index, indent, p)))
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "already visited.");
}
return(null);
}
}
_visited_extra[new Tuple <ATNState, int, int, List <int> >(state, token_index, indent, q)] = true;
_visited[new Tuple <ATNState, int, int>(state, token_index, indent)] = true;
List <List <Edge> > result = new List <List <Edge> >();
if (_stop_states.Contains(state))
{
if (_log_parse)
{
var n = _parser.Atn.ruleToStartState.Where(v => v.stateNumber == state.stateNumber);
var r = n.Any() ? n.FirstOrDefault().ruleIndex : -1;
var name = (r >= 0) ? (" " + _parser.RuleNames[r]) : "";
System.Console.Error.Write(
new String(' ', indent * 2)
+ "Entry "
+ here
+ " State "
+ state
+ name
+ " tokenIndex "
+ token_index
+ " "
+ input_token.Text
+ " return ");
}
List <List <Edge> > res = new List <List <Edge> >()
{
new List <Edge>()
{
t
}
};
if (_log_parse)
{
string str = PrintResult(res);
System.Console.Error.WriteLine(
str);
}
return(res);
}
// Search all transitions from state.
foreach (Transition transition in state.TransitionsArray)
{
List <List <Edge> > matches = null;
switch (transition.TransitionType)
{
case TransitionType.RULE:
{
RuleTransition rule = (RuleTransition)transition;
ATNState sub_state = rule.target;
matches = EnterState(q, new Edge()
{
_from = state,
_to = rule.target,
_follow = rule.followState,
_label = rule.Label,
_type = rule.TransitionType,
_index = token_index,
_index_at_transition = token_index
}, indent + 1);
if (matches != null && matches.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
if (matches != null)
{
List <List <Edge> > new_matches = new List <List <Edge> >();
foreach (List <Edge> match in matches)
{
Edge f = match.First(); // "to" is possibly final state of submachine.
Edge l = match.Last(); // "to" is start state of submachine.
bool is_final = _stop_states.Contains(f._to);
bool is_at_caret = f._index >= _cursor;
if (!is_final)
{
new_matches.Add(match);
}
else
{
List <List <Edge> > xxx = EnterState(q, new Edge()
{
_from = f._to,
_to = rule.followState,
_label = null,
_type = TransitionType.EPSILON,
_index = f._index,
_index_at_transition = f._index
}, indent + 1);
if (xxx != null && xxx.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
if (xxx != null)
{
foreach (List <Edge> y in xxx)
{
List <Edge> copy = y.ToList();
foreach (Edge g in match)
{
copy.Add(g);
}
new_matches.Add(copy);
}
}
}
}
matches = new_matches;
}
}
break;
case TransitionType.PREDICATE:
if (CheckPredicate((PredicateTransition)transition))
{
matches = EnterState(q, new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index,
_index_at_transition = token_index
}, indent + 1);
if (matches != null && matches.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
}
break;
case TransitionType.WILDCARD:
matches = EnterState(q, new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index + 1,
_index_at_transition = token_index
}, indent + 1);
if (matches != null && matches.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
break;
default:
if (transition.IsEpsilon)
{
matches = EnterState(q, new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index,
_index_at_transition = token_index
}, indent + 1);
if (matches != null && matches.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
}
else
{
IntervalSet set = transition.Label;
if (set != null && set.Count > 0)
{
if (transition.TransitionType == TransitionType.NOT_SET)
{
set = set.Complement(IntervalSet.Of(TokenConstants.MinUserTokenType, _parser.Atn.maxTokenType));
}
if (set.Contains(input_token.Type))
{
matches = EnterState(q, new Edge()
{
_from = state,
_to = transition.target,
_label = transition.Label,
_type = transition.TransitionType,
_index = token_index + 1,
_index_at_transition = token_index
}, indent + 1);
if (matches != null && matches.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "throwing exception.");
}
throw new Exception();
}
}
}
}
break;
}
if (matches != null)
{
foreach (List <Edge> match in matches)
{
List <Edge> x = match.ToList();
if (t != null)
{
x.Add(t);
Edge prev = null;
foreach (Edge z in x)
{
ATNState ff = z._to;
if (prev != null)
{
if (prev._from != ff)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "Fail "
+ PrintSingle(x));
Debug.Assert(false);
}
}
prev = z;
}
}
result.Add(x);
}
}
}
if (result.Count == 0)
{
if (_log_parse)
{
System.Console.Error.WriteLine(
new String(' ', indent * 2)
+ "result empty.");
}
return(null);
}
if (_log_parse)
{
var n = _parser.Atn.ruleToStartState.Where(v => v.stateNumber == state.stateNumber);
var r = n.Any() ? n.FirstOrDefault().ruleIndex : -1;
var name = (r >= 0) ? (" " + _parser.RuleNames[r]) : "";
System.Console.Error.Write(
new String(' ', indent * 2)
+ "Entry "
+ here
+ " State "
+ state
+ name
+ " tokenIndex "
+ token_index
+ " "
+ input_token.Text
+ " return ");
string str = PrintResult(result);
System.Console.Error.WriteLine(
str);
}
return(result);
}
