def hasSLLConflictTerminatingPrediction(cls, mode, configs):
# Configs in rule stop states indicate reaching the end of the decision
# rule (local context) or end of start rule (full context). If all
# configs meet this condition, then none of the configurations is able
# to match additional input so we terminate prediction.
#
if cls.allConfigsInRuleStopStates(configs):
return True
# pure SLL mode parsing
if mode == PredictionMode.SLL:
# Don't bother with combining configs from different semantic
# contexts if we can fail over to full LL; costs more time
# since we'll often fail over anyway.
if configs.hasSemanticContext:
# dup configs, tossing out semantic predicates
dup = ATNConfigSet()
for c in configs:
c = ATNConfig(config=c, semantic=SemanticContext.NONE)
dup.add(c)
configs = dup
# now we have combined contexts for configs with dissimilar preds
# pure SLL or combined SLL+LL mode parsing
altsets = cls.getConflictingAltSubsets(configs)
return cls.hasConflictingAltSet(
altsets) and not cls.hasStateAssociatedWithOneAlt(configs)
def hasSLLConflictTerminatingPrediction(cls, mode, configs):
# Configs in rule stop states indicate reaching the end of the decision
# rule (local context) or end of start rule (full context). If all
# configs meet this condition, then none of the configurations is able
# to match additional input so we terminate prediction.
#
if cls.allConfigsInRuleStopStates(configs):
return True
# pure SLL mode parsing
if mode == PredictionMode.SLL:
# Don't bother with combining configs from different semantic
# contexts if we can fail over to full LL; costs more time
# since we'll often fail over anyway.
if configs.hasSemanticContext:
# dup configs, tossing out semantic predicates
dup = ATNConfigSet()
for c in configs:
c = ATNConfig(c,SemanticContext.NONE)
dup.add(c)
configs = dup
# now we have combined contexts for configs with dissimilar preds
# pure SLL or combined SLL+LL mode parsing
altsets = cls.getConflictingAltSubsets(configs)
return cls.hasConflictingAltSet(altsets) and not cls.hasStateAssociatedWithOneAlt(configs)
def closure(self, input: InputStream, config: LexerATNConfig,
configs: ATNConfigSet, currentAltReachedAcceptState: bool,
speculative: bool, treatEofAsEpsilon: bool):
if self.debug:
print("closure(" + config.toString(self.recog, True) + ")")
if isinstance(config.state, RuleStopState):
if self.debug:
if self.recog is not None:
print("closure at %s rule stop %s\n",
self.recog.getRuleNames()[config.state.ruleIndex],
config)
else:
print("closure at rule stop %s\n", config)
if config.context is None or config.context.hasEmptyPath():
if config.context is None or config.context.isEmpty():
configs.add(config)
return True
else:
configs.add(
LexerATNConfig(state=config.state,
config=config,
context=PredictionContext.EMPTY))
currentAltReachedAcceptState = True
if config.context is not None and not config.context.isEmpty():
for i in range(0, len(config.context)):
if config.context.getReturnState(
i) != PredictionContext.EMPTY_RETURN_STATE:
newContext = config.context.getParent(
i) # "pop" return state
returnState = self.atn.states[
config.context.getReturnState(i)]
c = LexerATNConfig(state=returnState,
config=config,
context=newContext)
currentAltReachedAcceptState = self.closure(
input, c, configs, currentAltReachedAcceptState,
speculative, treatEofAsEpsilon)
return currentAltReachedAcceptState
# optimization
if not config.state.epsilonOnlyTransitions:
if not currentAltReachedAcceptState or not config.passedThroughNonGreedyDecision:
configs.add(config)
for t in config.state.transitions:
c = self.getEpsilonTarget(input, config, t, configs, speculative,
treatEofAsEpsilon)
if c is not None:
currentAltReachedAcceptState = self.closure(
input, c, configs, currentAltReachedAcceptState,
speculative, treatEofAsEpsilon)
return currentAltReachedAcceptState
def closure(
self,
input: InputStream,
config: LexerATNConfig,
configs: ATNConfigSet,
currentAltReachedAcceptState: bool,
speculative: bool,
treatEofAsEpsilon: bool,
):
if self.debug:
print("closure(" + config.toString(self.recog, True) + ")")
if isinstance(config.state, RuleStopState):
if self.debug:
if self.recog is not None:
print("closure at %s rule stop %s\n", self.recog.getRuleNames()[config.state.ruleIndex], config)
else:
print("closure at rule stop %s\n", config)
if config.context is None or config.context.hasEmptyPath():
if config.context is None or config.context.isEmpty():
configs.add(config)
return True
else:
configs.add(LexerATNConfig(state=config.state, config=config, context=PredictionContext.EMPTY))
currentAltReachedAcceptState = True
if config.context is not None and not config.context.isEmpty():
for i in range(0, len(config.context)):
if config.context.getReturnState(i) != PredictionContext.EMPTY_RETURN_STATE:
newContext = config.context.getParent(i) # "pop" return state
returnState = self.atn.states[config.context.getReturnState(i)]
c = LexerATNConfig(state=returnState, config=config, context=newContext)
currentAltReachedAcceptState = self.closure(
input, c, configs, currentAltReachedAcceptState, speculative, treatEofAsEpsilon
)
return currentAltReachedAcceptState
# optimization
if not config.state.epsilonOnlyTransitions:
if not currentAltReachedAcceptState or not config.passedThroughNonGreedyDecision:
configs.add(config)
for t in config.state.transitions:
c = self.getEpsilonTarget(input, config, t, configs, speculative, treatEofAsEpsilon)
if c is not None:
currentAltReachedAcceptState = self.closure(
input, c, configs, currentAltReachedAcceptState, speculative, treatEofAsEpsilon
)
return currentAltReachedAcceptState
