/**
* @param \Helstern\Nomsky\Grammar\Symbol\SymbolSet $set
* @param NormalizedProduction $production
* @param \Helstern\Nomsky\GrammarAnalysis\ParseSets\ParseSets $followSets
* @param \Helstern\Nomsky\GrammarAnalysis\ParseSets\ParseSets $firstSets
*
* @return bool
*/
public function processProduction(SymbolSet $set, NormalizedProduction $production, ParseSets $followSets, ParseSets $firstSets)
{
$rhs = $production->getRightHandSide();
$epsilonAdded = $this->firstSetCalculator->processSymbolList($set, $rhs, $firstSets);
if ($epsilonAdded) {
$lhs = $production->getLeftHandSide();
$otherSet = $followSets->getTerminalSet($lhs);
$set->addAll($otherSet);
}
return $epsilonAdded;
}
/**
* @param \Helstern\Nomsky\Grammar\Symbol\SymbolSet $set
* @param SymbolOccurrence $occurrence
* @param \Helstern\Nomsky\GrammarAnalysis\ParseSets\ParseSets $followSets
* @param \Helstern\Nomsky\GrammarAnalysis\ParseSets\ParseSets $firstSets
*
* @return bool
*/
public function processOccurrence(SymbolSet $set, SymbolOccurrence $occurrence, ParseSets $followSets, ParseSets $firstSets)
{
$symbol = $occurrence->getSymbol();
$isTerminal = SymbolTypeEquals::newInstanceMatchingTerminals();
if ($isTerminal->matchSymbol($symbol)) {
return false;
}
$following = $occurrence->getFollowing();
$epsilonAdded = $this->firstSetCalculator->processSymbolList($set, $following, $firstSets);
if ($epsilonAdded) {
$set->remove(new EpsilonSymbol());
$lhs = $occurrence->getProductionNonTerminal();
$otherSet = $followSets->getTerminalSet($lhs);
$set->addAll($otherSet);
}
return true;
}
