Merge pull request #2015 from rilian-la-te/optional-variant-any

vcmi: migrate to C++17

AI/BattleAI/BattleAI.cpp

@@ -134,7 +134,7 @@ BattleAction CBattleAI::activeStack( const CStack * stack )
 
 
 		//evaluate casting spell for spellcasting stack
-		boost::optional<PossibleSpellcast> bestSpellcast(boost::none);
+		std::optional<PossibleSpellcast> bestSpellcast(std::nullopt);
 		//TODO: faerie dragon type spell should be selected by server
 		SpellID creatureSpellToCast = cb->battleGetRandomStackSpell(CRandomGenerator::getDefault(), stack, CBattleInfoCallback::RANDOM_AIMED);
 		if(stack->hasBonusOfType(Bonus::SPELLCASTER) && stack->canCast() && creatureSpellToCast != SpellID::NONE)
@@ -157,7 +157,7 @@ BattleAction CBattleAI::activeStack( const CStack * stack )
 				std::sort(possibleCasts.begin(), possibleCasts.end(), [&](const PossibleSpellcast & lhs, const PossibleSpellcast & rhs) { return lhs.value > rhs.value; });
 				if(!possibleCasts.empty() && possibleCasts.front().value > 0)
 				{
-					bestSpellcast = boost::optional<PossibleSpellcast>(possibleCasts.front());
+					bestSpellcast = std::optional<PossibleSpellcast>(possibleCasts.front());
 				}
 			}
 		}
@@ -180,7 +180,7 @@ BattleAction CBattleAI::activeStack( const CStack * stack )
 			auto & bestAttack = evaluationResult.bestAttack;
 
 			//TODO: consider more complex spellcast evaluation, f.e. because "re-retaliation" during enemy move in same turn for melee attack etc.
-			if(bestSpellcast.is_initialized() && bestSpellcast->value > bestAttack.damageDiff())
+			if(bestSpellcast.has_value() && bestSpellcast->value > bestAttack.damageDiff())
 			{
 				// return because spellcast value is damage dealt and score is dps reduce
 				movesSkippedByDefense = 0;
@@ -219,7 +219,7 @@ BattleAction CBattleAI::activeStack( const CStack * stack )
 				);
 			}
 		}
-		else if(bestSpellcast.is_initialized())
+		else if(bestSpellcast.has_value())
 		{
 			movesSkippedByDefense = 0;
 			return BattleAction::makeCreatureSpellcast(stack, bestSpellcast->dest, bestSpellcast->spell->id);
@@ -801,7 +801,7 @@ void CBattleAI::print(const std::string &text) const
 	logAi->trace("%s Battle AI[%p]: %s", playerID.getStr(), this, text);
 }
 
-boost::optional<BattleAction> CBattleAI::considerFleeingOrSurrendering()
+std::optional<BattleAction> CBattleAI::considerFleeingOrSurrendering()
 {
 	BattleStateInfoForRetreat bs;
 
@@ -829,7 +829,7 @@ boost::optional<BattleAction> CBattleAI::considerFleeingOrSurrendering()
 
 	if(!bs.canFlee || !bs.canSurrender)
 	{
-		return boost::none;
+		return std::nullopt;
 	}
 
 	auto result = cb->makeSurrenderRetreatDecision(bs);

AI/BattleAI/BattleAI.h

@@ -73,7 +73,7 @@ public:
 
 	BattleAction activeStack(const CStack * stack) override; //called when it's turn of that stack
 
-	boost::optional<BattleAction> considerFleeingOrSurrendering();
+	std::optional<BattleAction> considerFleeingOrSurrendering();
 
 	void print(const std::string &text) const;
 	BattleAction useCatapult(const CStack *stack);

AI/Nullkiller/AIGateway.cpp

@@ -501,8 +501,7 @@ void AIGateway::showWorldViewEx(const std::vector<ObjectPosInfo> & objectPositio
 	NET_EVENT_HANDLER;
 }
 
-boost::optional<BattleAction> AIGateway::makeSurrenderRetreatDecision(
-	const BattleStateInfoForRetreat & battleState)
+std::optional<BattleAction> AIGateway::makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState)
 {
 	LOG_TRACE(logAi);
 	NET_EVENT_HANDLER;
@@ -516,7 +515,7 @@ boost::optional<BattleAction> AIGateway::makeSurrenderRetreatDecision(
 		return BattleAction::makeRetreat(battleState.ourSide);
 	}
 
-	return boost::none;
+	return std::nullopt;
 }
 
 

AI/Nullkiller/AIGateway.h

@@ -166,7 +166,7 @@ public:
 	void heroBonusChanged(const CGHeroInstance * hero, const Bonus & bonus, bool gain) override;
 	void showMarketWindow(const IMarket * market, const CGHeroInstance * visitor) override;
 	void showWorldViewEx(const std::vector<ObjectPosInfo> & objectPositions, bool showTerrain) override;
-	boost::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) override;
+	std::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) override;
 
 	void battleStart(const CCreatureSet * army1, const CCreatureSet * army2, int3 tile, const CGHeroInstance * hero1, const CGHeroInstance * hero2, bool side) override;
 	void battleEnd(const BattleResult * br, QueryID queryID) override;

AI/Nullkiller/Goals/Build.cpp

@@ -42,10 +42,10 @@ TGoalVec Build::getAllPossibleSubgoals()
 		auto expensiveBuilding = ai->ah->expensiveBuilding();
 
 		//handling for early town development to save money and focus on income
-		if(!t->hasBuilt(ai->ah->getMaxPossibleGoldBuilding(t)) && expensiveBuilding.is_initialized())
+		if(!t->hasBuilt(ai->ah->getMaxPossibleGoldBuilding(t)) && expensiveBuilding.has_value())
 		{
-			auto potentialBuilding = expensiveBuilding.get();
-			switch(expensiveBuilding.get().bid)
+			auto potentialBuilding = expensiveBuilding.value();
+			switch(expensiveBuilding.value().bid)
 			{
 			case BuildingID::TOWN_HALL:
 			case BuildingID::CITY_HALL:
@@ -61,15 +61,15 @@ TGoalVec Build::getAllPossibleSubgoals()
 			}
 		}
 
-		if(immediateBuilding.is_initialized())
+		if(immediateBuilding.has_value())
 		{
-			ret.push_back(sptr(BuildThis(immediateBuilding.get().bid, t).setpriority(2))); //prioritize buildings we can build quick
+			ret.push_back(sptr(BuildThis(immediateBuilding.value().bid, t).setpriority(2))); //prioritize buildings we can build quick
 		}
 		else //try build later
 		{
-			if(expensiveBuilding.is_initialized())
+			if(expensiveBuilding.has_value())
 			{
-				auto potentialBuilding = expensiveBuilding.get(); //gather resources for any we can't afford
+				auto potentialBuilding = expensiveBuilding.value(); //gather resources for any we can't afford
 				auto goal = ai->ah->whatToDo(potentialBuilding.price, sptr(BuildThis(potentialBuilding.bid, t).setpriority(0.5)));
 				ret.push_back(goal);
 			}

AI/Nullkiller/Goals/GatherArmy.cpp

@@ -97,7 +97,7 @@ TGoalVec GatherArmy::getAllPossibleSubgoals()
 
 			//Do not use below code for now, rely on generic Build. Code below needs to know a lot of town/resource context to do more good than harm
 			/*auto bid = ai->ah->canBuildAnyStructure(t, std::vector<BuildingID>(unitsSource, unitsSource + ARRAY_COUNT(unitsSource)), 1);
-			if (bid.is_initialized())
+			if (bid.has_value())
 			{
 				auto goal = sptr(BuildThis(bid.get(), t).setpriority(priority));
 				if (!ai->ah->containsObjective(goal)) //avoid loops caused by reserving same objective twice

AI/Nullkiller/Pathfinding/AINodeStorage.cpp

@@ -120,7 +120,7 @@ void AINodeStorage::clear()
 	turnDistanceLimit[HeroRole::SCOUT] = 255;
 }
 
-boost::optional<AIPathNode *> AINodeStorage::getOrCreateNode(
+std::optional<AIPathNode *> AINodeStorage::getOrCreateNode(
 	const int3 & pos, 
 	const EPathfindingLayer layer, 
 	const ChainActor * actor)
@@ -131,7 +131,7 @@ boost::optional<AIPathNode *> AINodeStorage::getOrCreateNode(
 
 	if(chains[0].blocked())
 	{
-		return boost::none;
+		return std::nullopt;
 	}
 
 	for(auto i = AIPathfinding::BUCKET_SIZE - 1; i >= 0; i--)
@@ -151,7 +151,7 @@ boost::optional<AIPathNode *> AINodeStorage::getOrCreateNode(
 		}
 	}
 
-	return boost::none;
+	return std::nullopt;
 }
 
 std::vector<CGPathNode *> AINodeStorage::getInitialNodes()
@@ -175,7 +175,7 @@ std::vector<CGPathNode *> AINodeStorage::getInitialNodes()
 		if(!allocated)
 			continue;
 
-		AIPathNode * initialNode = allocated.get();
+		AIPathNode * initialNode = allocated.value();
 
 		initialNode->inPQ = false;
 		initialNode->pq = nullptr;
@@ -289,10 +289,10 @@ std::vector<CGPathNode *> AINodeStorage::calculateNeighbours(
 		{
 			auto nextNode = getOrCreateNode(neighbour, i, srcNode->actor);
 
-			if(!nextNode || nextNode.get()->accessible == CGPathNode::NOT_SET)
+			if(!nextNode || nextNode.value()->accessible == CGPathNode::NOT_SET)
 				continue;
 
-			neighbours.push_back(nextNode.get());
+			neighbours.push_back(nextNode.value());
 		}
 	}
 	
@@ -722,7 +722,7 @@ void HeroChainCalculationTask::addHeroChain(const std::vector<ExchangeCandidate>
 			continue;
 		}
 
-		auto exchangeNode = chainNodeOptional.get();
+		auto exchangeNode = chainNodeOptional.value();
 
 		if(exchangeNode->action != CGPathNode::ENodeAction::UNKNOWN)
 		{
@@ -946,7 +946,7 @@ std::vector<CGPathNode *> AINodeStorage::calculateTeleportations(
 			if(!node)
 				continue;
 
-			neighbours.push_back(node.get());
+			neighbours.push_back(node.value());
 		}
 	}
 
@@ -1017,19 +1017,19 @@ struct TowmPortalFinder
 		return nullptr;
 	}
 
-	boost::optional<AIPathNode *> createTownPortalNode(const CGTownInstance * targetTown)
+	std::optional<AIPathNode *> createTownPortalNode(const CGTownInstance * targetTown)
 	{
 		auto bestNode = getBestInitialNodeForTownPortal(targetTown);
 
 		if(!bestNode)
-			return boost::none;
+			return std::nullopt;
 
 		auto nodeOptional = nodeStorage->getOrCreateNode(targetTown->visitablePos(), EPathfindingLayer::LAND, actor->castActor);
 
 		if(!nodeOptional)
-			return boost::none;
+			return std::nullopt;
 
-		AIPathNode * node = nodeOptional.get();
+		AIPathNode * node = nodeOptional.value();
 		float movementCost = (float)movementNeeded / (float)hero->maxMovePoints(EPathfindingLayer::LAND);
 
 		movementCost += bestNode->getCost();
@@ -1095,7 +1095,7 @@ void AINodeStorage::calculateTownPortal(
 #if NKAI_PATHFINDER_TRACE_LEVEL >= 1
 				logAi->trace("Adding town portal node at %s", targetTown->name);
 #endif
-				output.push_back(nodeOptional.get());
+				output.push_back(nodeOptional.value());
 			}
 		}
 	}

AI/Nullkiller/Pathfinding/AINodeStorage.h

@@ -232,7 +232,7 @@ public:
 		const AIPathNode * destinationNode,
 		const NodeRange & chains) const;
 
-	boost::optional<AIPathNode *> getOrCreateNode(const int3 & coord, const EPathfindingLayer layer, const ChainActor * actor);
+	std::optional<AIPathNode *> getOrCreateNode(const int3 & coord, const EPathfindingLayer layer, const ChainActor * actor);
 	std::vector<AIPath> getChainInfo(const int3 & pos, bool isOnLand) const;
 	bool isTileAccessible(const HeroPtr & hero, const int3 & pos, const EPathfindingLayer layer) const;
 	void setHeroes(std::map<const CGHeroInstance *, HeroRole> heroes);

AI/Nullkiller/Pathfinding/Rules/AILayerTransitionRule.cpp

@@ -131,7 +131,7 @@ namespace AIPathfinding
 
 			if(boatNodeOptional)
 			{
-				AIPathNode * boatNode = boatNodeOptional.get();
+				AIPathNode * boatNode = boatNodeOptional.value();
 
 				if(boatNode->action == CGPathNode::UNKNOWN)
 				{

AI/Nullkiller/Pathfinding/Rules/AIMovementAfterDestinationRule.cpp

@@ -139,17 +139,17 @@ namespace AIPathfinding
 		{
 			if(!destinationNode->actor->allowUseResources)
 			{
-				boost::optional<AIPathNode *> questNode = nodeStorage->getOrCreateNode(
+				std::optional<AIPathNode *> questNode = nodeStorage->getOrCreateNode(
 					destination.coord,
 					destination.node->layer,
 					destinationNode->actor->resourceActor);
 
-				if(!questNode || questNode.get()->getCost() < destination.cost)
+				if(!questNode || questNode.value()->getCost() < destination.cost)
 				{
 					return false;
 				}
 
-				destination.node = questNode.get();
+				destination.node = questNode.value();
 
 				nodeStorage->commit(destination, source);
 				AIPreviousNodeRule(nodeStorage).process(source, destination, pathfinderConfig, pathfinderHelper);
@@ -259,7 +259,7 @@ namespace AIPathfinding
 			return false;
 		}
 
-		AIPathNode * battleNode = battleNodeOptional.get();
+		auto * battleNode = battleNodeOptional.value();
 
 		if(battleNode->locked)
 		{

AI/VCAI/AIhelper.cpp

@@ -50,17 +50,17 @@ BuildingID AIhelper::getMaxPossibleGoldBuilding(const CGTownInstance * t)
 	return buildingManager->getMaxPossibleGoldBuilding(t);
 }
 
-boost::optional<PotentialBuilding> AIhelper::immediateBuilding() const
+std::optional<PotentialBuilding> AIhelper::immediateBuilding() const
 {
 	return buildingManager->immediateBuilding();
 }
 
-boost::optional<PotentialBuilding> AIhelper::expensiveBuilding() const
+std::optional<PotentialBuilding> AIhelper::expensiveBuilding() const
 {
 	return buildingManager->expensiveBuilding();
 }
 
-boost::optional<BuildingID> AIhelper::canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const
+std::optional<BuildingID> AIhelper::canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const
 {
 	return buildingManager->canBuildAnyStructure(t, buildList, maxDays);
 }

AI/VCAI/AIhelper.h

@@ -52,9 +52,9 @@ public:
 
 	bool getBuildingOptions(const CGTownInstance * t) override;
 	BuildingID getMaxPossibleGoldBuilding(const CGTownInstance * t);
-	boost::optional<PotentialBuilding> immediateBuilding() const override;
-	boost::optional<PotentialBuilding> expensiveBuilding() const override;
-	boost::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays = 7) const override;
+	std::optional<PotentialBuilding> immediateBuilding() const override;
+	std::optional<PotentialBuilding> expensiveBuilding() const override;
+	std::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays = 7) const override;
 
 	Goals::TGoalVec howToVisitTile(const HeroPtr & hero, const int3 & tile, bool allowGatherArmy = true) const override;
 	Goals::TGoalVec howToVisitObj(const HeroPtr & hero, ObjectIdRef obj, bool allowGatherArmy = true) const override;

AI/VCAI/BuildingManager.cpp

@@ -99,7 +99,7 @@ bool BuildingManager::tryBuildAnyStructure(const CGTownInstance * t, std::vector
 	return false; //Can't build anything
 }
 
-boost::optional<BuildingID> BuildingManager::canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const
+std::optional<BuildingID> BuildingManager::canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const
 {
 	for (const auto & building : buildList)
 	{
@@ -109,11 +109,11 @@ boost::optional<BuildingID> BuildingManager::canBuildAnyStructure(const CGTownIn
 		{
 			case EBuildingState::ALLOWED:
 			case EBuildingState::NO_RESOURCES: //TODO: allow this via optional parameter?
-				return boost::optional<BuildingID>(building);
+				return std::optional<BuildingID>(building);
 				break;
 		}
 	}
-	return boost::optional<BuildingID>(); //Can't build anything
+	return std::optional<BuildingID>(); //Can't build anything
 }
 
 bool BuildingManager::tryBuildNextStructure(const CGTownInstance * t, std::vector<BuildingID> buildList, unsigned int maxDays)
@@ -240,18 +240,18 @@ BuildingID BuildingManager::getMaxPossibleGoldBuilding(const CGTownInstance * t)
 		return BuildingID::VILLAGE_HALL;
 }
 
-boost::optional<PotentialBuilding> BuildingManager::immediateBuilding() const
+std::optional<PotentialBuilding> BuildingManager::immediateBuilding() const
 {
 	if (immediateBuildings.size())
-		return boost::optional<PotentialBuilding>(immediateBuildings.front()); //back? whatever
+		return std::optional<PotentialBuilding>(immediateBuildings.front()); //back? whatever
 	else
-		return boost::optional<PotentialBuilding>();
+		return std::optional<PotentialBuilding>();
 }
 
-boost::optional<PotentialBuilding> BuildingManager::expensiveBuilding() const
+std::optional<PotentialBuilding> BuildingManager::expensiveBuilding() const
 {
 	if (expensiveBuildings.size())
-		return boost::optional<PotentialBuilding>(expensiveBuildings.front());
+		return std::optional<PotentialBuilding>(expensiveBuildings.front());
 	else
-		return boost::optional<PotentialBuilding>();
+		return std::optional<PotentialBuilding>();
 }

AI/VCAI/BuildingManager.h

@@ -33,9 +33,9 @@ public:
 	virtual void setAI(VCAI * AI) = 0;
 
 	virtual bool getBuildingOptions(const CGTownInstance * t) = 0;
-	virtual boost::optional<PotentialBuilding> immediateBuilding() const = 0;
-	virtual boost::optional<PotentialBuilding> expensiveBuilding() const = 0;
-	virtual boost::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const = 0;
+	virtual std::optional<PotentialBuilding> immediateBuilding() const = 0;
+	virtual std::optional<PotentialBuilding> expensiveBuilding() const = 0;
+	virtual std::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays) const = 0;
 };
 
 class DLL_EXPORT BuildingManager : public IBuildingManager
@@ -52,9 +52,9 @@ public:
 	//try build anything in given town, and execute resulting Goal if any
 	bool getBuildingOptions(const CGTownInstance * t) override;
 	BuildingID getMaxPossibleGoldBuilding(const CGTownInstance * t);
-	boost::optional<PotentialBuilding> immediateBuilding() const override;
-	boost::optional<PotentialBuilding> expensiveBuilding() const override;
-	boost::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays = 7) const override;
+	std::optional<PotentialBuilding> immediateBuilding() const override;
+	std::optional<PotentialBuilding> expensiveBuilding() const override;
+	std::optional<BuildingID> canBuildAnyStructure(const CGTownInstance * t, const std::vector<BuildingID> & buildList, unsigned int maxDays = 7) const override;
 
 protected:
 

AI/VCAI/FuzzyEngines.cpp

@@ -399,12 +399,12 @@ float VisitObjEngine::evaluate(Goals::VisitObj & goal)
 		return -100; // FIXME: Added check when goal was used for hero instead of VisitHero, but crashes are bad anyway
 	}
 
-	boost::optional<int> objValueKnownByAI = MapObjectsEvaluator::getInstance().getObjectValue(obj);
+	std::optional<int> objValueKnownByAI = MapObjectsEvaluator::getInstance().getObjectValue(obj);
 	int objValue = 0;
 
-	if(objValueKnownByAI != boost::none) //consider adding value manipulation based on object instances on map
+	if(objValueKnownByAI != std::nullopt) //consider adding value manipulation based on object instances on map
 	{
-		objValue = std::min(std::max(objValueKnownByAI.get(), 0), 20000);
+		objValue = std::min(std::max(objValueKnownByAI.value(), 0), 20000);
 	}
 	else
 	{

AI/VCAI/Goals/Build.cpp

@@ -39,10 +39,10 @@ TGoalVec Build::getAllPossibleSubgoals()
 		auto expensiveBuilding = ai->ah->expensiveBuilding();
 
 		//handling for early town development to save money and focus on income
-		if(!t->hasBuilt(ai->ah->getMaxPossibleGoldBuilding(t)) && expensiveBuilding.is_initialized())
+		if(!t->hasBuilt(ai->ah->getMaxPossibleGoldBuilding(t)) && expensiveBuilding.has_value())
 		{
-			auto potentialBuilding = expensiveBuilding.get();
-			switch(expensiveBuilding.get().bid)
+			auto potentialBuilding = expensiveBuilding.value();
+			switch(expensiveBuilding.value().bid)
 			{
 			case BuildingID::TOWN_HALL:
 			case BuildingID::CITY_HALL:
@@ -58,15 +58,15 @@ TGoalVec Build::getAllPossibleSubgoals()
 			}
 		}
 
-		if(immediateBuilding.is_initialized())
+		if(immediateBuilding.has_value())
 		{
-			ret.push_back(sptr(BuildThis(immediateBuilding.get().bid, t).setpriority(2))); //prioritize buildings we can build quick
+			ret.push_back(sptr(BuildThis(immediateBuilding.value().bid, t).setpriority(2))); //prioritize buildings we can build quick
 		}
 		else //try build later
 		{
-			if(expensiveBuilding.is_initialized())
+			if(expensiveBuilding.has_value())
 			{
-				auto potentialBuilding = expensiveBuilding.get(); //gather resources for any we can't afford
+				auto potentialBuilding = expensiveBuilding.value(); //gather resources for any we can't afford
 				auto goal = ai->ah->whatToDo(potentialBuilding.price, sptr(BuildThis(potentialBuilding.bid, t).setpriority(0.5)));
 				ret.push_back(goal);
 			}

AI/VCAI/Goals/GatherArmy.cpp

@@ -94,7 +94,7 @@ TGoalVec GatherArmy::getAllPossibleSubgoals()
 
 			//Do not use below code for now, rely on generic Build. Code below needs to know a lot of town/resource context to do more good than harm
 			/*auto bid = ai->ah->canBuildAnyStructure(t, std::vector<BuildingID>(unitsSource, unitsSource + std::size(unitsSource)), 1);
-			if (bid.is_initialized())
+			if (bid.has_value())
 			{
 				auto goal = sptr(BuildThis(bid.get(), t).setpriority(priority));
 				if (!ai->ah->containsObjective(goal)) //avoid loops caused by reserving same objective twice

AI/VCAI/Goals/GatherTroops.cpp

@@ -96,7 +96,18 @@ TGoalVec GatherTroops::getAllPossibleSubgoals()
 		auto creature = VLC->creatures()->getByIndex(objid);
 		if(t->subID == creature->getFaction()) //TODO: how to force AI to build unupgraded creatures? :O
 		{
-			auto creatures = vstd::tryAt(t->town->creatures, creature->getLevel() - 1);
+			auto tryFindCreature = [&]() -> std::optional<std::vector<CreatureID>>
+			{
+				if(vstd::isValidIndex(t->town->creatures, creature->getLevel() - 1))
+				{
+					auto itr = t->town->creatures.begin();
+					std::advance(itr, creature->getLevel() - 1);
+					return make_optional(*itr);
+				}
+				return std::nullopt;
+			};
+
+			auto creatures = tryFindCreature();
 			if(!creatures)
 				continue;
 

AI/VCAI/MapObjectsEvaluator.cpp

@@ -28,9 +28,9 @@ MapObjectsEvaluator::MapObjectsEvaluator()
 			auto handler = VLC->objtypeh->getHandlerFor(primaryID, secondaryID);
 			if(handler && !handler->isStaticObject())
 			{
-				if(handler->getAiValue() != boost::none)
+				if(handler->getAiValue() != std::nullopt)
 				{
-					objectDatabase[CompoundMapObjectID(primaryID, secondaryID)] = handler->getAiValue().get();
+					objectDatabase[CompoundMapObjectID(primaryID, secondaryID)] = handler->getAiValue().value();
 				}
 				else //some default handling when aiValue not found, objects that require advanced properties (unavailable from handler) get their value calculated in getObjectValue
 				{
@@ -41,7 +41,7 @@ MapObjectsEvaluator::MapObjectsEvaluator()
 	}
 }
 
-boost::optional<int> MapObjectsEvaluator::getObjectValue(int primaryID, int secondaryID) const
+std::optional<int> MapObjectsEvaluator::getObjectValue(int primaryID, int secondaryID) const
 {
 	CompoundMapObjectID internalIdentifier = CompoundMapObjectID(primaryID, secondaryID);
 	auto object = objectDatabase.find(internalIdentifier);
@@ -49,10 +49,10 @@ boost::optional<int> MapObjectsEvaluator::getObjectValue(int primaryID, int seco
 		return object->second;
 
 	logGlobal->trace("Unknown object for AI, ID: " + std::to_string(primaryID) + ", SubID: " + std::to_string(secondaryID));
-	return boost::optional<int>();
+	return std::optional<int>();
 }
 
-boost::optional<int> MapObjectsEvaluator::getObjectValue(const CGObjectInstance * obj) const
+std::optional<int> MapObjectsEvaluator::getObjectValue(const CGObjectInstance * obj) const
 {
 	if(obj->ID == Obj::HERO)
 	{

AI/VCAI/MapObjectsEvaluator.h

@@ -18,8 +18,8 @@ private:
 public:
 	MapObjectsEvaluator();
 	static MapObjectsEvaluator & getInstance();
-	boost::optional<int> getObjectValue(int primaryID, int secondaryID) const;
-	boost::optional<int> getObjectValue(const CGObjectInstance * obj) const;
+	std::optional<int> getObjectValue(int primaryID, int secondaryID) const;
+	std::optional<int> getObjectValue(const CGObjectInstance * obj) const;
 	void addObjectData(int primaryID, int secondaryID, int value);
 	void removeObjectData(int primaryID, int secondaryID);
 };

AI/VCAI/Pathfinding/AINodeStorage.cpp

@@ -83,7 +83,7 @@ bool AINodeStorage::isBattleNode(const CGPathNode * node) const
 	return (getAINode(node)->chainMask & BATTLE_CHAIN) > 0;
 }
 
-boost::optional<AIPathNode *> AINodeStorage::getOrCreateNode(const int3 & pos, const EPathfindingLayer layer, int chainNumber)
+std::optional<AIPathNode *> AINodeStorage::getOrCreateNode(const int3 & pos, const EPathfindingLayer layer, int chainNumber)
 {
 	auto chains = nodes[layer][pos.z][pos.x][pos.y];
 
@@ -102,15 +102,13 @@ boost::optional<AIPathNode *> AINodeStorage::getOrCreateNode(const int3 & pos, c
 		}
 	}
 
-	return boost::none;
+	return std::nullopt;
 }
 
 std::vector<CGPathNode *> AINodeStorage::getInitialNodes()
 {
 	auto hpos = hero->visitablePos();
-	auto initialNode =
-		getOrCreateNode(hpos, hero->boat ? EPathfindingLayer::SAIL : EPathfindingLayer::LAND, NORMAL_CHAIN)
-		.get();
+	auto initialNode = getOrCreateNode(hpos, hero->boat ? EPathfindingLayer::SAIL : EPathfindingLayer::LAND, NORMAL_CHAIN).value();
 
 	initialNode->turns = 0;
 	initialNode->moveRemains = hero->movement;
@@ -171,10 +169,10 @@ std::vector<CGPathNode *> AINodeStorage::calculateNeighbours(
 		{
 			auto nextNode = getOrCreateNode(neighbour, i, srcNode->chainMask);
 
-			if(!nextNode || nextNode.get()->accessible == CGPathNode::NOT_SET)
+			if(!nextNode || nextNode.value()->accessible == CGPathNode::NOT_SET)
 				continue;
 
-			neighbours.push_back(nextNode.get());
+			neighbours.push_back(nextNode.value());
 		}
 	}
 
@@ -207,7 +205,7 @@ std::vector<CGPathNode *> AINodeStorage::calculateTeleportations(
 			if(!node)
 				continue;
 
-			neighbours.push_back(node.get());
+			neighbours.push_back(node.value());
 		}
 	}
 
@@ -273,7 +271,7 @@ void AINodeStorage::calculateTownPortalTeleportations(
 				logAi->trace("Adding town portal node at %s", targetTown->name);
 #endif
 
-				AIPathNode * node = nodeOptional.get();
+				AIPathNode * node = nodeOptional.value();
 
 				node->theNodeBefore = source.node;
 				node->specialAction.reset(new AIPathfinding::TownPortalAction(targetTown));

AI/VCAI/Pathfinding/AINodeStorage.h

@@ -107,7 +107,7 @@ public:
 
 	bool isBattleNode(const CGPathNode * node) const;
 	bool hasBetterChain(const PathNodeInfo & source, CDestinationNodeInfo & destination) const;
-	boost::optional<AIPathNode *> getOrCreateNode(const int3 & coord, const EPathfindingLayer layer, int chainNumber);
+	std::optional<AIPathNode *> getOrCreateNode(const int3 & coord, const EPathfindingLayer layer, int chainNumber);
 	std::vector<AIPath> getChainInfo(const int3 & pos, bool isOnLand) const;
 	bool isTileAccessible(const int3 & pos, const EPathfindingLayer layer) const;
 

AI/VCAI/Pathfinding/PathfindingManager.cpp

@@ -114,7 +114,7 @@ Goals::TGoalVec PathfindingManager::findPath(
 	const std::function<Goals::TSubgoal(int3)> doVisitTile) const
 {
 	Goals::TGoalVec result;
-	boost::optional<uint64_t> armyValueRequired;
+	std::optional<uint64_t> armyValueRequired;
 	uint64_t danger;
 
 	std::vector<AIPath> chainInfo = pathfinder->getPathInfo(hero, dest);
@@ -165,12 +165,12 @@ Goals::TGoalVec PathfindingManager::findPath(
 
 			if(!armyValueRequired || armyValueRequired > danger)
 			{
-				armyValueRequired = boost::make_optional(danger);
+				armyValueRequired = std::make_optional(danger);
 			}
 		}
 	}
 
-	danger = armyValueRequired.get_value_or(0);
+	danger = armyValueRequired.value_or(0);
 
 	if(allowGatherArmy && danger > 0)
 	{

AI/VCAI/Pathfinding/Rules/AILayerTransitionRule.cpp

@@ -120,7 +120,7 @@ namespace AIPathfinding
 
 			if(boatNodeOptional)
 			{
-				AIPathNode * boatNode = boatNodeOptional.get();
+				AIPathNode * boatNode = boatNodeOptional.value();
 
 				if(boatNode->action == CGPathNode::UNKNOWN)
 				{

AI/VCAI/Pathfinding/Rules/AIMovementAfterDestinationRule.cpp

@@ -106,7 +106,7 @@ namespace AIPathfinding
 				return;
 			}
 
-			AIPathNode *  battleNode = battleNodeOptional.get();
+			auto * battleNode = battleNodeOptional.value();
 
 			if(battleNode->locked)
 			{

AI/VCAI/VCAI.cpp

@@ -1241,14 +1241,14 @@ void VCAI::recruitCreatures(const CGDwelling * d, const CArmedInstance * recruit
 	}
 }
 
-bool VCAI::isGoodForVisit(const CGObjectInstance * obj, HeroPtr h, boost::optional<float> movementCostLimit)
+bool VCAI::isGoodForVisit(const CGObjectInstance * obj, HeroPtr h, std::optional<float> movementCostLimit)
 {
 	int3 op = obj->visitablePos();
 	auto paths = ah->getPathsToTile(h, op);
 
 	for(const auto & path : paths)
 	{
-		if(movementCostLimit && movementCostLimit.get() < path.movementCost())
+		if(movementCostLimit && movementCostLimit.value() < path.movementCost())
 			return false;
 
 		if(isGoodForVisit(obj, h, path))
@@ -1363,18 +1363,13 @@ void VCAI::wander(HeroPtr h)
 		});
 
 		int pass = 0;
-		std::vector<boost::optional<float>> distanceLimits =
-		{
-			1.0,
-			2.0,
-			boost::none
-		};
+		std::vector<std::optional<float>> distanceLimits = {1.0, 2.0, std::nullopt};
 
 		while(!dests.size() && pass < distanceLimits.size())
 		{
 			auto & distanceLimit = distanceLimits[pass];
 
-			logAi->debug("Looking for wander destination pass=%i, cost limit=%f", pass, distanceLimit.get_value_or(-1.0));
+			logAi->debug("Looking for wander destination pass=%i, cost limit=%f", pass, distanceLimit.value_or(-1.0));
 
 			vstd::copy_if(visitableObjs, std::back_inserter(dests), [&](ObjectIdRef obj) -> bool
 			{

AI/VCAI/VCAI.h

@@ -217,7 +217,7 @@ public:
 	void completeGoal(Goals::TSubgoal goal); //safely removes goal from reserved hero
 
 	void recruitHero(const CGTownInstance * t, bool throwing = false);
-	bool isGoodForVisit(const CGObjectInstance * obj, HeroPtr h, boost::optional<float> movementCostLimit = boost::none);
+	bool isGoodForVisit(const CGObjectInstance * obj, HeroPtr h, std::optional<float> movementCostLimit = std::nullopt);
 	bool isGoodForVisit(const CGObjectInstance * obj, HeroPtr h, const AIPath & path) const;
 	//void recruitCreatures(const CGTownInstance * t);
 	void recruitCreatures(const CGDwelling * d, const CArmedInstance * recruiter);

CCallback.cpp

@@ -90,7 +90,7 @@ bool CCallback::upgradeCreature(const CArmedInstance *obj, SlotID stackPos, Crea
 
 void CCallback::endTurn()
 {
-	logGlobal->trace("Player %d ended his turn.", player.get().getNum());
+	logGlobal->trace("Player %d ended his turn.", player->getNum());
 	EndTurn pack;
 	sendRequest(&pack);
 }
@@ -306,8 +306,8 @@ void CCallback::buildBoat( const IShipyard *obj )
 	sendRequest(&bb);
 }
 
-CCallback::CCallback(CGameState * GS, boost::optional<PlayerColor> Player, CClient * C)
-	: CBattleCallback(Player, C)
+CCallback::CCallback(CGameState * GS, std::optional<PlayerColor> Player, CClient * C):
+	CBattleCallback(Player, C)
 {
 	gs = GS;
 
@@ -380,7 +380,7 @@ scripting::Pool * CBattleCallback::getContextPool() const
 }
 #endif
 
-CBattleCallback::CBattleCallback(boost::optional<PlayerColor> Player, CClient *C )
+CBattleCallback::CBattleCallback(std::optional<PlayerColor> Player, CClient * C)
 {
 	player = Player;
 	cl = C;
@@ -395,8 +395,7 @@ bool CBattleCallback::battleMakeTacticAction( BattleAction * action )
 	return true;
 }
 
-boost::optional<BattleAction> CBattleCallback::makeSurrenderRetreatDecision(
-	const BattleStateInfoForRetreat & battleState)
+std::optional<BattleAction> CBattleCallback::makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState)
 {
-	return cl->playerint[getPlayerID().get()]->makeSurrenderRetreatDecision(battleState);
+	return cl->playerint[getPlayerID().value()]->makeSurrenderRetreatDecision(battleState);
 }

CCallback.h

@@ -54,7 +54,7 @@ public:
 	//battle
 	virtual int battleMakeAction(const BattleAction * action) = 0;//for casting spells by hero - DO NOT use it for moving active stack
 	virtual bool battleMakeTacticAction(BattleAction * action) = 0; // performs tactic phase actions
-	virtual boost::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) = 0;
+	virtual std::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) = 0;
 };
 
 class IGameActionCallback
@@ -113,10 +113,10 @@ protected:
 	CClient *cl;
 
 public:
-	CBattleCallback(boost::optional<PlayerColor> Player, CClient *C);
+	CBattleCallback(std::optional<PlayerColor> Player, CClient * C);
 	int battleMakeAction(const BattleAction * action) override;//for casting spells by hero - DO NOT use it for moving active stack
 	bool battleMakeTacticAction(BattleAction * action) override; // performs tactic phase actions
-	boost::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) override;
+	std::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState) override;
 
 #if SCRIPTING_ENABLED
 	scripting::Pool * getContextPool() const override;
@@ -131,7 +131,7 @@ class CCallback : public CPlayerSpecificInfoCallback,
 	public CBattleCallback
 {
 public:
-	CCallback(CGameState * GS, boost::optional<PlayerColor> Player, CClient *C);
+	CCallback(CGameState * GS, std::optional<PlayerColor> Player, CClient * C);
 	virtual ~CCallback();
 
 	//client-specific functionalities (pathfinding)

Global.h

@@ -101,6 +101,7 @@ static_assert(sizeof(bool) == 1, "Bool needs to be 1 byte in size.");
 #define _USE_MATH_DEFINES
 
 #include <algorithm>
+#include <any>
 #include <array>
 #include <atomic>
 #include <bitset>
@@ -144,14 +145,13 @@ static_assert(sizeof(bool) == 1, "Bool needs to be 1 byte in size.");
 #endif
 
 #include <boost/algorithm/string.hpp>
-#include <boost/any.hpp>
-#include <boost/current_function.hpp>
 #include <boost/crc.hpp>
+#include <boost/current_function.hpp>
 #include <boost/date_time/posix_time/posix_time.hpp>
 #include <boost/date_time/posix_time/posix_time_io.hpp>
 #include <boost/filesystem.hpp>
-#include <boost/filesystem/path.hpp>
 #include <boost/filesystem/fstream.hpp>
+#include <boost/filesystem/path.hpp>
 #include <boost/format.hpp>
 #include <boost/functional/hash.hpp>
 #include <boost/lexical_cast.hpp>
@@ -159,14 +159,11 @@ static_assert(sizeof(bool) == 1, "Bool needs to be 1 byte in size.");
 #include <boost/locale/generator.hpp>
 #endif
 #include <boost/logic/tribool.hpp>
-#include <boost/optional.hpp>
-#include <boost/optional/optional_io.hpp>
+#include <boost/multi_array.hpp>
 #include <boost/range/adaptor/filtered.hpp>
 #include <boost/range/adaptor/reversed.hpp>
 #include <boost/range/algorithm.hpp>
 #include <boost/thread.hpp>
-#include <boost/variant.hpp>
-#include <boost/multi_array.hpp>
 
 #ifndef M_PI
 #  define M_PI 3.14159265358979323846
@@ -576,28 +573,6 @@ namespace vstd
 		return i >= 0  &&  i < c.size();
 	}
 
-	template <typename Container, typename Index>
-	boost::optional<typename Container::const_reference> tryAt(const Container &c, Index i)
-	{
-		if(isValidIndex(c, i))
-		{
-			auto itr = c.begin();
-			std::advance(itr, i);
-			return *itr;
-		}
-		return boost::none;
-	}
-
-	template <typename Container, typename Pred>
-	static boost::optional<typename Container::const_reference> tryFindIf(const Container &r, const Pred &t)
-	{
-		auto pos = range::find_if(r, t);
-		if(pos == boost::end(r))
-			return boost::none;
-		else
-			return *pos;
-	}
-
 	template <typename Container>
 	typename Container::const_reference atOrDefault(const Container &r, size_t index, const typename Container::const_reference &defaultValue)
 	{
@@ -668,8 +643,8 @@ namespace vstd
 		return false;
 	}
 
-	template <class M, class Key, class F>
-	typename M::mapped_type & getOrCompute(M & m, Key const & k, F f)
+	template<class M, class Key, class F>
+	typename M::mapped_type & getOrCompute(M & m, const Key & k, F f)
 	{
 		typedef typename M::mapped_type V;
 

client/CPlayerInterface.cpp

@@ -103,7 +103,7 @@ std::shared_ptr<BattleInterface> CPlayerInterface::battleInt;
 enum  EMoveState {STOP_MOVE, WAITING_MOVE, CONTINUE_MOVE, DURING_MOVE};
 CondSh<EMoveState> stillMoveHero(STOP_MOVE); //used during hero movement
 
-struct HeroObjectRetriever : boost::static_visitor<const CGHeroInstance *>
+struct HeroObjectRetriever
 {
 	const CGHeroInstance * operator()(const ConstTransitivePtr<CGHeroInstance> &h) const
 	{
@@ -328,7 +328,7 @@ void CPlayerInterface::heroMoved(const TryMoveHero & details, bool verbose)
 	if (details.result == TryMoveHero::EMBARK || details.result == TryMoveHero::DISEMBARK)
 	{
 		if(hero->getRemovalSound() && hero->tempOwner == playerID)
-			CCS->soundh->playSound(hero->getRemovalSound().get());
+			CCS->soundh->playSound(hero->getRemovalSound().value());
 	}
 
 	adventureInt->minimap->updateTile(hero->convertToVisitablePos(details.start));
@@ -463,7 +463,7 @@ void CPlayerInterface::heroVisit(const CGHeroInstance * visitor, const CGObjectI
 	if(start && visitedObj)
 	{
 		if(visitedObj->getVisitSound())
-			CCS->soundh->playSound(visitedObj->getVisitSound().get());
+			CCS->soundh->playSound(visitedObj->getVisitSound().value());
 	}
 }
 
@@ -1530,7 +1530,7 @@ void CPlayerInterface::objectRemoved(const CGObjectInstance * obj)
 	if(LOCPLINT->cb->getCurrentPlayer() == playerID && obj->getRemovalSound())
 	{
 		waitWhileDialog();
-		CCS->soundh->playSound(obj->getRemovalSound().get());
+		CCS->soundh->playSound(obj->getRemovalSound().value());
 	}
 	CGI->mh->waitForOngoingAnimations();
 
@@ -1758,7 +1758,7 @@ void CPlayerInterface::acceptTurn()
 
 		if(optDaysWithoutCastle)
 		{
-			auto daysWithoutCastle = optDaysWithoutCastle.get();
+			auto daysWithoutCastle = optDaysWithoutCastle.value();
 			if (daysWithoutCastle < 6)
 			{
 				text.addTxt(MetaString::ARRAY_TXT,128); //%s, you only have %d days left to capture a town or you will be banished from this land.
@@ -1915,7 +1915,7 @@ void CPlayerInterface::requestReturningToMainMenu(bool won)
 
 void CPlayerInterface::askToAssembleArtifact(const ArtifactLocation &al)
 {
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), al.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), al.artHolder);
 	if(hero)
 	{
 		auto art = hero->getArt(al.slot);
@@ -1932,14 +1932,14 @@ void CPlayerInterface::askToAssembleArtifact(const ArtifactLocation &al)
 void CPlayerInterface::artifactPut(const ArtifactLocation &al)
 {
 	EVENT_HANDLER_CALLED_BY_CLIENT;
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), al.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), al.artHolder);
 	updateInfo(hero);
 }
 
 void CPlayerInterface::artifactRemoved(const ArtifactLocation &al)
 {
 	EVENT_HANDLER_CALLED_BY_CLIENT;
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), al.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), al.artHolder);
 	updateInfo(hero);
 	for(auto isa : GH.listInt)
 	{
@@ -1954,7 +1954,7 @@ void CPlayerInterface::artifactRemoved(const ArtifactLocation &al)
 void CPlayerInterface::artifactMoved(const ArtifactLocation &src, const ArtifactLocation &dst)
 {
 	EVENT_HANDLER_CALLED_BY_CLIENT;
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), dst.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), dst.artHolder);
 	updateInfo(hero);
 
 	bool redraw = true;
@@ -1983,7 +1983,7 @@ void CPlayerInterface::bulkArtMovementStart(size_t numOfArts)
 void CPlayerInterface::artifactAssembled(const ArtifactLocation &al)
 {
 	EVENT_HANDLER_CALLED_BY_CLIENT;
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), al.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), al.artHolder);
 	updateInfo(hero);
 	for(auto isa : GH.listInt)
 	{
@@ -1996,7 +1996,7 @@ void CPlayerInterface::artifactAssembled(const ArtifactLocation &al)
 void CPlayerInterface::artifactDisassembled(const ArtifactLocation &al)
 {
 	EVENT_HANDLER_CALLED_BY_CLIENT;
-	auto hero = boost::apply_visitor(HeroObjectRetriever(), al.artHolder);
+	auto hero = std::visit(HeroObjectRetriever(), al.artHolder);
 	updateInfo(hero);
 	for(auto isa : GH.listInt)
 	{

client/Client.cpp

@@ -421,7 +421,7 @@ void CClient::initPlayerEnvironments()
 	
 	if(settings["session"]["spectate"].Bool())
 	{
-		playerEnvironments[PlayerColor::SPECTATOR] = std::make_shared<CPlayerEnvironment>(PlayerColor::SPECTATOR, this, std::make_shared<CCallback>(gs, boost::none, this));
+		playerEnvironments[PlayerColor::SPECTATOR] = std::make_shared<CPlayerEnvironment>(PlayerColor::SPECTATOR, this, std::make_shared<CCallback>(gs, std::nullopt, this));
 	}
 }
 
@@ -626,7 +626,7 @@ void CClient::commenceTacticPhaseForInt(std::shared_ptr<CBattleGameInterface> ba
 		battleInt->yourTacticPhase(gs->curB->tacticDistance);
 		if(gs && !!gs->curB && gs->curB->tacticDistance) //while awaiting for end of tactics phase, many things can happen (end of battle... or game)
 		{
-			MakeAction ma(BattleAction::makeEndOFTacticPhase(gs->curB->playerToSide(battleInt->playerID).get()));
+			MakeAction ma(BattleAction::makeEndOFTacticPhase(gs->curB->playerToSide(battleInt->playerID).value()));
 			sendRequest(&ma, battleInt->playerID);
 		}
 	}

client/Client.h

@@ -140,7 +140,7 @@ public:
 
 	std::map<PlayerColor, std::vector<std::shared_ptr<IBattleEventsReceiver>>> additionalBattleInts;
 
-	boost::optional<BattleAction> curbaction;
+	std::optional<BattleAction> curbaction;
 
 	CClient();
 	~CClient();

client/NetPacksClient.cpp

@@ -762,7 +762,7 @@ void ApplyClientNetPackVisitor::visitBattleAttack(BattleAttack & pack)
 
 void ApplyFirstClientNetPackVisitor::visitStartAction(StartAction & pack)
 {
-	cl.curbaction = boost::make_optional(pack.ba);
+	cl.curbaction = std::make_optional(pack.ba);
 	callBattleInterfaceIfPresentForBothSides(cl, &IBattleEventsReceiver::actionStarted, pack.ba);
 }
 

client/adventureMap/CAdvMapInt.cpp

@@ -853,7 +853,7 @@ void CAdvMapInt::keyPressed(const SDL_Keycode & key)
 	}
 }
 
-boost::optional<Point> CAdvMapInt::keyToMoveDirection(const SDL_Keycode & key)
+std::optional<Point> CAdvMapInt::keyToMoveDirection(const SDL_Keycode & key)
 {
 	switch (key) {
 		case SDLK_DOWN:  return Point( 0, +1);
@@ -871,7 +871,7 @@ boost::optional<Point> CAdvMapInt::keyToMoveDirection(const SDL_Keycode & key)
 		case SDLK_KP_8: return Point( 0, -1);
 		case SDLK_KP_9: return Point(+1, -1);
 	}
-	return boost::none;
+	return std::nullopt;
 }
 
 void CAdvMapInt::select(const CArmedInstance *sel, bool centerView)

client/adventureMap/CAdvMapInt.h

@@ -143,7 +143,7 @@ private:
 
 	const CGObjectInstance *getActiveObject(const int3 &tile);
 
-	boost::optional<Point> keyToMoveDirection(const SDL_Keycode & key);
+	std::optional<Point> keyToMoveDirection(const SDL_Keycode & key);
 
 public:
 	CAdvMapInt();

client/adventureMap/MapAudioPlayer.cpp

@@ -136,7 +136,7 @@ std::vector<std::string> MapAudioPlayer::getAmbientSounds(const int3 & tile)
 			logGlobal->warn("Already removed object %d found on tile! (%d %d %d)", objectID.getNum(), tile.x, tile.y, tile.z);
 
 		if(object && object->getAmbientSound())
-			result.push_back(object->getAmbientSound().get());
+			result.push_back(object->getAmbientSound().value());
 	}
 
 	if(CGI->mh->getMap()->isCoastalTile(tile))

client/battle/BattleInterface.cpp

@@ -252,7 +252,7 @@ void BattleInterface::giveCommand(EActionType action, BattleHex tile, si32 addit
 	}
 
 	auto ba = new BattleAction(); //is deleted in CPlayerInterface::stacksController->getActiveStack()()
-	ba->side = side.get();
+	ba->side = side.value();
 	ba->actionType = action;
 	ba->aimToHex(tile);
 	ba->actionSubtype = additional;

client/battle/BattleInterfaceClasses.cpp

@@ -68,7 +68,7 @@ void BattleConsole::showAll(SDL_Surface * to)
 std::vector<std::string> BattleConsole::getVisibleText()
 {
 	// high priority texts that hide battle log entries
-	for (auto const & text : {consoleText, hoverText} )
+	for(const auto & text : {consoleText, hoverText})
 	{
 		if (text.empty())
 			continue;
@@ -94,7 +94,7 @@ std::vector<std::string> BattleConsole::splitText(const std::string &text)
 
 	boost::split(lines, text, boost::is_any_of("\n"));
 
-	for (auto const & line : lines)
+	for(const auto & line : lines)
 	{
 		if (graphics->fonts[FONT_SMALL]->getStringWidth(text) < pos.w)
 		{
@@ -679,7 +679,7 @@ int32_t StackQueue::getSiegeShooterIconID()
 	return owner.siegeController->getSiegedTown()->town->faction->getIndex();
 }
 
-boost::optional<uint32_t> StackQueue::getHoveredUnitIdIfAny() const
+std::optional<uint32_t> StackQueue::getHoveredUnitIdIfAny() const
 {
 	for(const auto & stackBox : stackBoxes)
 	{
@@ -689,7 +689,7 @@ boost::optional<uint32_t> StackQueue::getHoveredUnitIdIfAny() const
 		}
 	}
 
-	return boost::none;
+	return std::nullopt;
 }
 
 StackQueue::StackBox::StackBox(StackQueue * owner):
@@ -758,7 +758,7 @@ void StackQueue::StackBox::setUnit(const battle::Unit * unit, size_t turn)
 	}
 	else
 	{
-		boundUnitID = boost::none;
+		boundUnitID = std::nullopt;
 		background->colorize(PlayerColor::NEUTRAL);
 		icon->visible = false;
 		icon->setFrame(0);
@@ -769,7 +769,7 @@ void StackQueue::StackBox::setUnit(const battle::Unit * unit, size_t turn)
 	}
 }
 
-boost::optional<uint32_t> StackQueue::StackBox::getBoundUnitID() const
+std::optional<uint32_t> StackQueue::StackBox::getBoundUnitID() const
 {
 	return boundUnitID;
 }

client/battle/BattleInterfaceClasses.h

@@ -166,7 +166,7 @@ class StackQueue : public CIntObject
 	class StackBox : public CIntObject
 	{
 		StackQueue * owner;
-		boost::optional<uint32_t> boundUnitID;
+		std::optional<uint32_t> boundUnitID;
 		bool highlighted = false;
 
 	public:
@@ -178,7 +178,7 @@ class StackQueue : public CIntObject
 		StackBox(StackQueue * owner);
 		void setUnit(const battle::Unit * unit, size_t turn = 0);
 		void toggleHighlight(bool value);
-		boost::optional<uint32_t> getBoundUnitID() const;
+		std::optional<uint32_t> getBoundUnitID() const;
 
 		void show(SDL_Surface * to) override;
 	};
@@ -197,7 +197,7 @@ public:
 
 	StackQueue(bool Embedded, BattleInterface & owner);
 	void update();
-	boost::optional<uint32_t> getHoveredUnitIdIfAny() const;
+	std::optional<uint32_t> getHoveredUnitIdIfAny() const;
 
 	void show(SDL_Surface * to) override;
 };

client/battle/BattleObstacleController.cpp

@@ -66,7 +66,7 @@ void BattleObstacleController::loadObstacleImage(const CObstacleInstance & oi)
 
 void BattleObstacleController::obstacleRemoved(const std::vector<ObstacleChanges> & obstacles)
 {
-	for (auto const & oi : obstacles)
+	for(const auto & oi : obstacles)
 	{
 		auto & obstacle = oi.data["obstacle"];
 
@@ -97,11 +97,11 @@ void BattleObstacleController::obstacleRemoved(const std::vector<ObstacleChanges
 
 void BattleObstacleController::obstaclePlaced(const std::vector<std::shared_ptr<const CObstacleInstance>> & obstacles)
 {
-	for (auto const & oi : obstacles)
+	for(const auto & oi : obstacles)
 	{
 		auto side = owner.curInt->cb->playerToSide(owner.curInt->playerID);
 
-		if(!oi->visibleForSide(side.get(),owner.curInt->cb->battleHasNativeStack(side.get())))
+		if(!oi->visibleForSide(side.value(), owner.curInt->cb->battleHasNativeStack(side.value())))
 			continue;
 
 		auto animation = std::make_shared<CAnimation>(oi->getAppearAnimation());

client/battle/BattleStacksController.cpp

@@ -281,7 +281,7 @@ std::shared_ptr<IImage> BattleStacksController::getStackAmountBox(const CStack *
 
 	int effectsPositivness = 0;
 
-	for ( auto const & spellID : activeSpells)
+	for(const auto & spellID : activeSpells)
 		effectsPositivness += CGI->spellh->objects.at(spellID)->positiveness;
 
 	if (effectsPositivness > 0)
@@ -336,7 +336,7 @@ void BattleStacksController::showStackAmountBox(Canvas & canvas, const CStack *
 void BattleStacksController::showStack(Canvas & canvas, const CStack * stack)
 {
 	ColorFilter fullFilter = ColorFilter::genEmptyShifter();
-	for (auto const & filter : stackFilterEffects)
+	for(const auto & filter : stackFilterEffects)
 	{
 		if (filter.target == stack)
 			fullFilter = ColorFilter::genCombined(fullFilter, filter.effect);
@@ -814,7 +814,7 @@ void BattleStacksController::updateHoveredStacks()
 {
 	auto newStacks = selectHoveredStacks();
 
-	for (auto const * stack : mouseHoveredStacks)
+	for(const auto * stack : mouseHoveredStacks)
 	{
 		if (vstd::contains(newStacks, stack))
 			continue;
@@ -825,7 +825,7 @@ void BattleStacksController::updateHoveredStacks()
 			stackAnimation[stack->ID]->setBorderColor(AnimationControls::getNoBorder());
 	}
 
-	for (auto const * stack : newStacks)
+	for(const auto * stack : newStacks)
 	{
 		if (vstd::contains(mouseHoveredStacks, stack))
 			continue;
@@ -848,7 +848,7 @@ std::vector<const CStack *> BattleStacksController::selectHoveredStacks()
 		return {};
 
 	auto hoveredQueueUnitId = owner.windowObject->getQueueHoveredUnitId();
-	if(hoveredQueueUnitId.is_initialized())
+	if(hoveredQueueUnitId.has_value())
 	{
 		return { owner.curInt->cb->battleGetStackByID(hoveredQueueUnitId.value(), true) };
 	}
@@ -889,7 +889,7 @@ std::vector<const CStack *> BattleStacksController::selectHoveredStacks()
 const std::vector<uint32_t> BattleStacksController::getHoveredStacksUnitIds() const
 {
 	auto result = std::vector<uint32_t>();
-	for (auto const * stack : mouseHoveredStacks)
+	for(const auto * stack : mouseHoveredStacks)
 	{
 		result.push_back(stack->unitId());
 	}

client/battle/BattleWindow.cpp

@@ -590,7 +590,7 @@ void BattleWindow::blockUI(bool on)
 	}
 }
 
-boost::optional<uint32_t> BattleWindow::getQueueHoveredUnitId()
+std::optional<uint32_t> BattleWindow::getQueueHoveredUnitId()
 {
 	return queue->getHoveredUnitIdIfAny();
 }

client/battle/BattleWindow.h

@@ -80,7 +80,7 @@ public:
 	void updateQueue();
 
 	/// Get mouse-hovered battle queue unit ID if any found
-	boost::optional<uint32_t> getQueueHoveredUnitId();
+	std::optional<uint32_t> getQueueHoveredUnitId();
 
 	void activate() override;
 	void deactivate() override;

client/widgets/Buttons.cpp

@@ -57,15 +57,15 @@ void CButton::update()
 		redraw();
 }
 
-void CButton::setBorderColor(boost::optional<SDL_Color> borderColor)
+void CButton::setBorderColor(std::optional<SDL_Color> borderColor)
 {
 	setBorderColor(borderColor, borderColor, borderColor, borderColor);
 }
 
-void CButton::setBorderColor(boost::optional<SDL_Color> normalBorderColor,
-                             boost::optional<SDL_Color> pressedBorderColor,
-                             boost::optional<SDL_Color> blockedBorderColor,
-                             boost::optional<SDL_Color> highlightedBorderColor)
+void CButton::setBorderColor(std::optional<SDL_Color> normalBorderColor,
+							 std::optional<SDL_Color> pressedBorderColor,
+							 std::optional<SDL_Color> blockedBorderColor,
+							 std::optional<SDL_Color> highlightedBorderColor)
 {
 	stateToBorderColor[NORMAL] = normalBorderColor;
 	stateToBorderColor[PRESSED] = pressedBorderColor;
@@ -591,7 +591,7 @@ void CSlider::setScrollBounds(const Rect & bounds )
 
 void CSlider::clearScrollBounds()
 {
-	scrollBounds = boost::none;
+	scrollBounds = std::nullopt;
 }
 
 int CSlider::getAmount() const

client/widgets/Buttons.h

@@ -52,7 +52,7 @@ private:
 
 	std::array<int, 4> stateToIndex; // mapping of button state to index of frame in animation
 	std::array<std::string, 4> hoverTexts; //texts for statusbar, if empty - first entry will be used
-	std::array<boost::optional<SDL_Color>, 4> stateToBorderColor; // mapping of button state to border color
+	std::array<std::optional<SDL_Color>, 4> stateToBorderColor; // mapping of button state to border color
 	std::string helpBox; //for right-click help
 
 	std::shared_ptr<CAnimImage> image; //image for this button
@@ -73,13 +73,13 @@ public:
 
 	// sets border color for each button state;
 	// if it's set, the button will have 1-px border around it with this color
-	void setBorderColor(boost::optional<SDL_Color> normalBorderColor,
-	                    boost::optional<SDL_Color> pressedBorderColor,
-	                    boost::optional<SDL_Color> blockedBorderColor,
-	                    boost::optional<SDL_Color> highlightedBorderColor);
+	void setBorderColor(std::optional<SDL_Color> normalBorderColor,
+						std::optional<SDL_Color> pressedBorderColor,
+						std::optional<SDL_Color> blockedBorderColor,
+						std::optional<SDL_Color> highlightedBorderColor);
 
 	// sets the same border color for all button states.
-	void setBorderColor(boost::optional<SDL_Color> borderColor);
+	void setBorderColor(std::optional<SDL_Color> borderColor);
 
 	/// adds one more callback to on-click actions
 	void addCallback(std::function<void()> callback);
@@ -229,7 +229,7 @@ class CSlider : public CIntObject
 	std::shared_ptr<CButton> right;
 	std::shared_ptr<CButton> slider;
 
-	boost::optional<Rect> scrollBounds;
+	std::optional<Rect> scrollBounds;
 
 	int capacity;//how many elements can be active at same time (e.g. hero list = 5)
 	int positions; //number of highest position (0 if there is only one)

client/widgets/Images.cpp

@@ -85,7 +85,7 @@ void CPicture::show(SDL_Surface * to)
 void CPicture::showAll(SDL_Surface * to)
 {
 	if(bg && visible)
-		bg->draw(to, pos.x, pos.y, srcRect.get_ptr());
+		bg->draw(to, pos.x, pos.y, srcRect.has_value() ? &srcRect.value() : nullptr);
 }
 
 void CPicture::setAlpha(int value)

client/widgets/Images.h

@@ -30,7 +30,7 @@ class CPicture : public CIntObject
 
 public:
 	/// if set, only specified section of internal image will be rendered
-	boost::optional<Rect> srcRect;
+	std::optional<Rect> srcRect;
 
 	/// If set to true, iamge will be redrawn on each frame
 	bool needRefresh;

client/windows/CCreatureWindow.cpp

@@ -64,9 +64,9 @@ public:
 	const CGHeroInstance * owner;
 
 	// temporary objects which should be kept as copy if needed
-	boost::optional<CommanderLevelInfo> levelupInfo;
-	boost::optional<StackDismissInfo> dismissInfo;
-	boost::optional<StackUpgradeInfo> upgradeInfo;
+	std::optional<CommanderLevelInfo> levelupInfo;
+	std::optional<StackDismissInfo> dismissInfo;
+	std::optional<StackUpgradeInfo> upgradeInfo;
 
 	// misc fields
 	unsigned int creatureCount;
@@ -246,8 +246,8 @@ CStackWindow::BonusLineSection::BonusLineSection(CStackWindow * owner, size_t li
 	}
 }
 
-CStackWindow::BonusesSection::BonusesSection(CStackWindow * owner, int yOffset, boost::optional<size_t> preferredSize)
-	: CWindowSection(owner, "", yOffset)
+CStackWindow::BonusesSection::BonusesSection(CStackWindow * owner, int yOffset, std::optional<size_t> preferredSize):
+	CWindowSection(owner, "", yOffset)
 {
 	OBJECT_CONSTRUCTION_CAPTURING(255-DISPOSE);
 
@@ -255,7 +255,7 @@ CStackWindow::BonusesSection::BonusesSection(CStackWindow * owner, int yOffset,
 	static const int itemHeight = 59;
 
 	size_t totalSize = (owner->activeBonuses.size() + 1) / 2;
-	size_t visibleSize = preferredSize ? preferredSize.get() : std::min<size_t>(3, totalSize);
+	size_t visibleSize = preferredSize.value_or(std::min<size_t>(3, totalSize));
 
 	pos.w = owner->pos.w;
 	pos.h = itemHeight * (int)visibleSize;
@@ -292,7 +292,7 @@ CStackWindow::ButtonsSection::ButtonsSection(CStackWindow * owner, int yOffset)
 		// used space overlaps with commander switch button
 		// besides - should commander really be upgradeable?
 
-		UnitView::StackUpgradeInfo & upgradeInfo = parent->info->upgradeInfo.get();
+		auto & upgradeInfo = parent->info->upgradeInfo.value();
 		const size_t buttonsToCreate = std::min<size_t>(upgradeInfo.info.newID.size(), upgrade.size());
 
 		for(size_t buttonIndex = 0; buttonIndex < buttonsToCreate; buttonIndex++)
@@ -686,8 +686,8 @@ CStackWindow::CStackWindow(const CStackInstance * stack, std::function<void()> d
 	info->creature = stack->type;
 	info->creatureCount = stack->count;
 
-	info->upgradeInfo = boost::make_optional(UnitView::StackUpgradeInfo());
-	info->dismissInfo = boost::make_optional(UnitView::StackDismissInfo());
+	info->upgradeInfo = std::make_optional(UnitView::StackUpgradeInfo());
+	info->dismissInfo = std::make_optional(UnitView::StackDismissInfo());
 	info->upgradeInfo->info = upgradeInfo;
 	info->upgradeInfo->callback = callback;
 	info->dismissInfo->callback = dismiss;
@@ -716,7 +716,7 @@ CStackWindow::CStackWindow(const CCommanderInstance * commander, std::vector<ui3
 	info->creature = commander->type;
 	info->commander = commander;
 	info->creatureCount = 1;
-	info->levelupInfo = boost::make_optional(UnitView::CommanderLevelInfo());
+	info->levelupInfo = std::make_optional(UnitView::CommanderLevelInfo());
 	info->levelupInfo->skills = skills;
 	info->levelupInfo->callback = callback;
 	info->owner = dynamic_cast<const CGHeroInstance *> (commander->armyObj);
@@ -814,7 +814,7 @@ void CStackWindow::initSections()
 
 		commanderMainSection = std::make_shared<CommanderMainSection>(this, 0);
 
-		auto size = boost::make_optional<size_t>((info->levelupInfo) ? 4 : 3);
+		auto size = std::make_optional<size_t>((info->levelupInfo) ? 4 : 3);
 		commanderBonusesSection = std::make_shared<BonusesSection>(this, 0, size);
 		deactivateObj(commanderBonusesSection);
 

client/windows/CCreatureWindow.h

@@ -83,7 +83,7 @@ class CStackWindow : public CWindowObject
 	{
 		std::shared_ptr<CListBox> lines;
 	public:
-		BonusesSection(CStackWindow * owner, int yOffset, boost::optional<size_t> preferredSize = boost::optional<size_t>());
+		BonusesSection(CStackWindow * owner, int yOffset, std::optional<size_t> preferredSize = std::optional<size_t>());
 	};
 
 	class ButtonsSection : public CWindowSection

lib/CArtHandler.cpp

@@ -740,15 +740,28 @@ void CArtHandler::erasePickedArt(const ArtifactID & id)
 {
 	CArtifact *art = objects[id];
 
-	if(auto artifactList = listFromClass(art->aClass))
+	if(!(art->aClass & CArtifact::ART_SPECIAL))
 	{
-		if(artifactList->empty())
-			fillList(*artifactList, art->aClass);
+		auto & artifactList = treasures;
+		switch(art->aClass)
+		{
+			case CArtifact::ART_MINOR:
+				artifactList = minors;
+				break;
+			case CArtifact::ART_MAJOR:
+				artifactList = majors;
+				break;
+			case CArtifact::ART_RELIC:
+				artifactList = relics;
+				break;
+		}
+		if(artifactList.empty())
+			fillList(artifactList, art->aClass);
 
-		auto itr = vstd::find(*artifactList, art);
-		if(itr != artifactList->end())
+		auto itr = vstd::find(artifactList, art);
+		if(itr != artifactList.end())
 		{
-			artifactList->erase(itr);
+			artifactList.erase(itr);
 		}
 		else
 			logMod->warn("Problem: cannot erase artifact %s from list, it was not present", art->getNameTranslated());
@@ -758,23 +771,6 @@ void CArtHandler::erasePickedArt(const ArtifactID & id)
 		logMod->warn("Problem: cannot find list for artifact %s, strange class. (special?)", art->getNameTranslated());
 }
 
-boost::optional<std::vector<CArtifact*>&> CArtHandler::listFromClass( CArtifact::EartClass artifactClass )
-{
-	switch(artifactClass)
-	{
-	case CArtifact::ART_TREASURE:
-		return treasures;
-	case CArtifact::ART_MINOR:
-		return minors;
-	case CArtifact::ART_MAJOR:
-		return majors;
-	case CArtifact::ART_RELIC:
-		return relics;
-	default: //special artifacts should not be erased
-		return boost::optional<std::vector<CArtifact*>&>();
-	}
-}
-
 void CArtHandler::fillList( std::vector<CArtifact*> &listToBeFilled, CArtifact::EartClass artifactClass )
 {
 	assert(listToBeFilled.empty());

lib/CArtHandler.h

@@ -244,8 +244,6 @@ public:
 
 	void fillList(std::vector<CArtifact*> &listToBeFilled, CArtifact::EartClass artifactClass); //fills given empty list with allowed artifacts of given class. No side effects
 
-	boost::optional<std::vector<CArtifact*>&> listFromClass(CArtifact::EartClass artifactClass);
-
 	static CArtifact::EartClass stringToClass(const std::string & className); //TODO: rework EartClass to make this a constructor
 
 	/// Gets a artifact ID randomly and removes the selected artifact from this handler.

lib/CCreatureHandler.cpp

@@ -408,7 +408,7 @@ CCreatureHandler::CCreatureHandler()
 
 const CCreature * CCreatureHandler::getCreature(const std::string & scope, const std::string & identifier) const
 {
-	boost::optional<si32> index = VLC->modh->identifiers.getIdentifier(scope, "creature", identifier);
+	std::optional<si32> index = VLC->modh->identifiers.getIdentifier(scope, "creature", identifier);
 
 	if(!index)
 		throw std::runtime_error("Creature not found "+identifier);

lib/CCreatureSet.cpp

@@ -624,7 +624,7 @@ void CCreatureSet::armyChanged()
 
 }
 
-void CCreatureSet::serializeJson(JsonSerializeFormat & handler, const std::string & fieldName, const boost::optional<int> fixedSize)
+void CCreatureSet::serializeJson(JsonSerializeFormat & handler, const std::string & fieldName, const std::optional<int> fixedSize)
 {
 	if(handler.saving && stacks.empty())
 		return;
@@ -640,7 +640,7 @@ void CCreatureSet::serializeJson(JsonSerializeFormat & handler, const std::strin
 			vstd::amax(sz, p.first.getNum()+1);
 
 		if(fixedSize)
-			vstd::amax(sz, fixedSize.get());
+			vstd::amax(sz, fixedSize.value());
 
 		a.resize(sz, JsonNode::JsonType::DATA_STRUCT);
 

lib/CCreatureSet.h

@@ -75,7 +75,7 @@ public:
 		uint8_t upgrade;
 	};
 	// helper variable used during loading map, when object (hero or town) have creatures that must have same alignment.
-	boost::optional<RandomStackInfo> randomStack;
+	std::optional<RandomStackInfo> randomStack;
 
 	const CArmedInstance * const & armyObj; //stack must be part of some army, army must be part of some object
 	TExpType experience;//commander needs same amount of exp as hero
@@ -286,7 +286,7 @@ public:
 		h & formation;
 	}
 
-	void serializeJson(JsonSerializeFormat & handler, const std::string & fieldName, const boost::optional<int> fixedSize = boost::none);
+	void serializeJson(JsonSerializeFormat & handler, const std::string & fieldName, const std::optional<int> fixedSize = std::nullopt);
 
 	operator bool() const
 	{

lib/CGameInfoCallback.cpp

@@ -401,7 +401,7 @@ int CGameInfoCallback::getDate(Date::EDateType mode) const
 	return gs->getDate(mode);
 }
 
-bool CGameInfoCallback::isVisible(int3 pos, const boost::optional<PlayerColor> & Player) const
+bool CGameInfoCallback::isVisible(int3 pos, const std::optional<PlayerColor> & Player) const
 {
 	//boost::shared_lock<boost::shared_mutex> lock(*gs->mx);
 	return gs->isVisible(pos, Player);
@@ -412,7 +412,7 @@ bool CGameInfoCallback::isVisible(int3 pos) const
 	return isVisible(pos, player);
 }
 
-bool CGameInfoCallback::isVisible( const CGObjectInstance *obj,const boost::optional<PlayerColor> & Player) const
+bool CGameInfoCallback::isVisible(const CGObjectInstance * obj, const std::optional<PlayerColor> & Player) const
 {
 	return gs->isVisible(obj, Player);
 }
@@ -521,8 +521,8 @@ EDiggingStatus CGameInfoCallback::getTileDigStatus(int3 tile, bool verbose) cons
 //TODO: typedef?
 std::shared_ptr<const boost::multi_array<TerrainTile*, 3>> CGameInfoCallback::getAllVisibleTiles() const
 {
-	assert(player.is_initialized());
-	const auto * team = getPlayerTeam(player.get());
+	assert(player.has_value());
+	const auto * team = getPlayerTeam(player.value());
 
 	size_t width = gs->map->width;
 	size_t height = gs->map->height;
@@ -619,9 +619,9 @@ const CMapHeader * CGameInfoCallback::getMapHeader() const
 	return gs->map;
 }
 
-bool CGameInfoCallback::hasAccess(boost::optional<PlayerColor> playerId) const
+bool CGameInfoCallback::hasAccess(std::optional<PlayerColor> playerId) const
 {
-	return !player || player.get().isSpectator() || gs->getPlayerRelations( *playerId, *player ) != PlayerRelations::ENEMIES;
+	return !player || player->isSpectator() || gs->getPlayerRelations(*playerId, *player) != PlayerRelations::ENEMIES;
 }
 
 EPlayerStatus::EStatus CGameInfoCallback::getPlayerStatus(PlayerColor player, bool verbose) const
@@ -703,7 +703,7 @@ PlayerColor CGameInfoCallback::getCurrentPlayer() const
 	return gs->currentPlayer;
 }
 
-CGameInfoCallback::CGameInfoCallback(CGameState * GS, boost::optional<PlayerColor> Player):
+CGameInfoCallback::CGameInfoCallback(CGameState * GS, std::optional<PlayerColor> Player):
 	gs(GS)
 {
 	player = std::move(Player);
@@ -754,7 +754,7 @@ std::vector < const CGHeroInstance *> CPlayerSpecificInfoCallback::getHeroesInfo
 	return ret;
 }
 
-boost::optional<PlayerColor> CPlayerSpecificInfoCallback::getMyColor() const
+std::optional<PlayerColor> CPlayerSpecificInfoCallback::getMyColor() const
 {
 	return player;
 }
@@ -882,7 +882,7 @@ const TeamState * CGameInfoCallback::getTeam( TeamID teamID ) const
 	if (team != gs->teams.end())
 	{
 		const TeamState *ret = &team->second;
-		if (!player.is_initialized()) //neutral (or invalid) player
+		if(!player.has_value()) //neutral (or invalid) player
 			return ret;
 		else
 		{

lib/CGameInfoCallback.h

@@ -133,8 +133,8 @@ protected:
 	CGameState * gs;//todo: replace with protected const getter, only actual Server and Client objects should hold game state
 
 	CGameInfoCallback() = default;
-	CGameInfoCallback(CGameState *GS, boost::optional<PlayerColor> Player);
-	bool hasAccess(boost::optional<PlayerColor> playerId) const;
+	CGameInfoCallback(CGameState * GS, std::optional<PlayerColor> Player);
+	bool hasAccess(std::optional<PlayerColor> playerId) const;
 
 	bool canGetFullInfo(const CGObjectInstance *obj) const; //true we player owns obj or ally owns obj or privileged mode
 	bool isOwnedOrVisited(const CGObjectInstance *obj) const;
@@ -157,9 +157,9 @@ public:
 	virtual const PlayerSettings * getPlayerSettings(PlayerColor color) const;
 
 	//map
-	virtual bool isVisible(int3 pos, const boost::optional<PlayerColor> & Player) const;
-	virtual bool isVisible(const CGObjectInstance *obj, const boost::optional<PlayerColor> & Player) const;
-	virtual bool isVisible(const CGObjectInstance *obj) const;
+	virtual bool isVisible(int3 pos, const std::optional<PlayerColor> & Player) const;
+	virtual bool isVisible(const CGObjectInstance * obj, const std::optional<PlayerColor> & Player) const;
+	virtual bool isVisible(const CGObjectInstance * obj) const;
 	virtual bool isVisible(int3 pos) const;
 
 
@@ -234,7 +234,7 @@ public:
 	virtual int howManyTowns() const;
 	virtual int howManyHeroes(bool includeGarrisoned = true) const;
 	virtual int3 getGrailPos(double *outKnownRatio);
-	virtual boost::optional<PlayerColor> getMyColor() const;
+	virtual std::optional<PlayerColor> getMyColor() const;
 
 	virtual std::vector <const CGTownInstance *> getTownsInfo(bool onlyOur = true) const; //true -> only owned; false -> all visible
 	virtual int getHeroSerial(const CGHeroInstance * hero, bool includeGarrisoned=true) const;

lib/CGameInterface.h

@@ -110,9 +110,9 @@ public:
 
 	virtual void showWorldViewEx(const std::vector<ObjectPosInfo> & objectPositions, bool showTerrain){};
 
-	virtual boost::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState)
+	virtual std::optional<BattleAction> makeSurrenderRetreatDecision(const BattleStateInfoForRetreat & battleState)
 	{
-		return boost::none;
+		return std::nullopt;
 	}
 
 	virtual void saveGame(BinarySerializer & h, const int version) = 0;

lib/CGameState.cpp

@@ -925,7 +925,7 @@ void CGameState::initNewGame(const IMapService * mapService, bool allowSavingRan
 
 void CGameState::initCampaign()
 {
-	logGlobal->info("Open campaign map file: %d", scenarioOps->campState->currentMap.get());
+	logGlobal->info("Open campaign map file: %d", scenarioOps->campState->currentMap.value());
 	map = scenarioOps->campState->getMap();
 }
 
@@ -1068,7 +1068,7 @@ void CGameState::placeCampaignHeroes()
 	{
 		// place bonus hero
 		auto campaignBonus = scenarioOps->campState->getBonusForCurrentMap();
-		bool campaignGiveHero = campaignBonus && campaignBonus.get().type == CScenarioTravel::STravelBonus::HERO;
+		bool campaignGiveHero = campaignBonus && campaignBonus->type == CScenarioTravel::STravelBonus::HERO;
 
 		if(campaignGiveHero)
 		{
@@ -1568,7 +1568,7 @@ void CGameState::initHeroes()
 
 void CGameState::giveCampaignBonusToHero(CGHeroInstance * hero)
 {
-	const boost::optional<CScenarioTravel::STravelBonus> & curBonus = scenarioOps->campState->getBonusForCurrentMap();
+	const std::optional<CScenarioTravel::STravelBonus> & curBonus = scenarioOps->campState->getBonusForCurrentMap();
 	if(!curBonus)
 		return;
 
@@ -2234,7 +2234,7 @@ void CGameState::updateRumor()
 	while(!rumor.update(rumorId, rumorExtra));
 }
 
-bool CGameState::isVisible(int3 pos, const boost::optional<PlayerColor> & player) const
+bool CGameState::isVisible(int3 pos, const std::optional<PlayerColor> & player) const
 {
 	if (!map->isInTheMap(pos))
 		return false;
@@ -2248,7 +2248,7 @@ bool CGameState::isVisible(int3 pos, const boost::optional<PlayerColor> & player
 	return (*getPlayerTeam(*player)->fogOfWarMap)[pos.z][pos.x][pos.y];
 }
 
-bool CGameState::isVisible( const CGObjectInstance *obj, const boost::optional<PlayerColor> & player) const
+bool CGameState::isVisible(const CGObjectInstance * obj, const std::optional<PlayerColor> & player) const
 {
 	if(!player)
 		return true;
@@ -2433,7 +2433,7 @@ bool CGameState::checkForVictory(const PlayerColor & player, const EventConditio
 		case EventCondition::DAYS_WITHOUT_TOWN:
 		{
 			if (p->daysWithoutCastle)
-				return p->daysWithoutCastle.get() >= condition.value;
+				return p->daysWithoutCastle >= condition.value;
 			else
 				return false;
 		}

lib/CGameState.h

@@ -202,9 +202,8 @@ public:
 	void obtainPlayersStats(SThievesGuildInfo & tgi, int level); //fills tgi with info about other players that is available at given level of thieves' guild
 	std::map<ui32, ConstTransitivePtr<CGHeroInstance> > unusedHeroesFromPool(); //heroes pool without heroes that are available in taverns
 
-
-	bool isVisible(int3 pos, const boost::optional<PlayerColor> & player) const override;
-	bool isVisible(const CGObjectInstance *obj, const boost::optional<PlayerColor> & player) const override;
+	bool isVisible(int3 pos, const std::optional<PlayerColor> & player) const override;
+	bool isVisible(const CGObjectInstance * obj, const std::optional<PlayerColor> & player) const override;
 
 	int getDate(Date::EDateType mode=Date::DAY) const override; //mode=0 - total days in game, mode=1 - day of week, mode=2 - current week, mode=3 - current month
 

lib/CModHandler.cpp

@@ -156,7 +156,7 @@ void CIdentifierStorage::tryRequestIdentifier(const std::string & type, const Js
 	requestIdentifier(ObjectCallback::fromNameAndType(name.meta, type, name.String(), callback, true));
 }
 
-boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scope, const std::string & type, const std::string & name, bool silent)
+std::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scope, const std::string & type, const std::string & name, bool silent)
 {
 	auto idList = getPossibleIdentifiers(ObjectCallback::fromNameAndType(scope, type, name, std::function<void(si32)>(), silent));
 
@@ -165,10 +165,10 @@ boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scop
 	if (!silent)
 		logMod->error("Failed to resolve identifier %s of type %s from mod %s", name , type ,scope);
 
-	return boost::optional<si32>();
+	return std::optional<si32>();
 }
 
-boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & type, const JsonNode & name, bool silent)
+std::optional<si32> CIdentifierStorage::getIdentifier(const std::string & type, const JsonNode & name, bool silent)
 {
 	auto idList = getPossibleIdentifiers(ObjectCallback::fromNameAndType(name.meta, type, name.String(), std::function<void(si32)>(), silent));
 
@@ -177,10 +177,10 @@ boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & type
 	if (!silent)
 		logMod->error("Failed to resolve identifier %s of type %s from mod %s", name.String(), type, name.meta);
 
-	return boost::optional<si32>();
+	return std::optional<si32>();
 }
 
-boost::optional<si32> CIdentifierStorage::getIdentifier(const JsonNode & name, bool silent)
+std::optional<si32> CIdentifierStorage::getIdentifier(const JsonNode & name, bool silent)
 {
 	auto idList = getPossibleIdentifiers(ObjectCallback::fromNameWithType(name.meta, name.String(), std::function<void(si32)>(), silent));
 
@@ -189,10 +189,10 @@ boost::optional<si32> CIdentifierStorage::getIdentifier(const JsonNode & name, b
 	if (!silent)
 		logMod->error("Failed to resolve identifier %s from mod %s", name.String(), name.meta);
 
-	return boost::optional<si32>();
+	return std::optional<si32>();
 }
 
-boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scope, const std::string & fullName, bool silent)
+std::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scope, const std::string & fullName, bool silent)
 {
 	auto idList = getPossibleIdentifiers(ObjectCallback::fromNameWithType(scope, fullName, std::function<void(si32)>(), silent));
 
@@ -201,7 +201,7 @@ boost::optional<si32> CIdentifierStorage::getIdentifier(const std::string & scop
 	if (!silent)
 		logMod->error("Failed to resolve identifier %s from mod %s", fullName, scope);
 
-	return boost::optional<si32>();
+	return std::optional<si32>();
 }
 
 void CIdentifierStorage::registerObject(const std::string & scope, const std::string & type, const std::string & name, si32 identifier)

lib/CModHandler.h

@@ -99,10 +99,10 @@ public:
 	void tryRequestIdentifier(const std::string & type, const JsonNode & name, const std::function<void(si32)> & callback);
 
 	/// get identifier immediately. If identifier is not know and not silent call will result in error message
-	boost::optional<si32> getIdentifier(const std::string & scope, const std::string & type, const std::string & name, bool silent = false);
-	boost::optional<si32> getIdentifier(const std::string & type, const JsonNode & name, bool silent = false);
-	boost::optional<si32> getIdentifier(const JsonNode & name, bool silent = false);
-	boost::optional<si32> getIdentifier(const std::string & scope, const std::string & fullName, bool silent = false);
+	std::optional<si32> getIdentifier(const std::string & scope, const std::string & type, const std::string & name, bool silent = false);
+	std::optional<si32> getIdentifier(const std::string & type, const JsonNode & name, bool silent = false);
+	std::optional<si32> getIdentifier(const JsonNode & name, bool silent = false);
+	std::optional<si32> getIdentifier(const std::string & scope, const std::string & fullName, bool silent = false);
 
 	/// registers new object
 	void registerObject(const std::string & scope, const std::string & type, const std::string & name, si32 identifier);

lib/CPathfinder.cpp

@@ -897,7 +897,7 @@ void CPathfinderHelper::initializePatrol()
 		if(hero->patrol.patrolRadius)
 		{
 			state = PATROL_RADIUS;
-			gs->getTilesInRange(patrolTiles, hero->patrol.initialPos, hero->patrol.patrolRadius, boost::optional<PlayerColor>(), 0, int3::DIST_MANHATTAN);
+			gs->getTilesInRange(patrolTiles, hero->patrol.initialPos, hero->patrol.patrolRadius, std::optional<PlayerColor>(), 0, int3::DIST_MANHATTAN);
 		}
 		else
 			state = PATROL_LOCKED;
@@ -1100,8 +1100,12 @@ void TurnInfo::updateHeroBonuses(Bonus::BonusType type, const CSelector& sel) co
 	}
 }
 
-CPathfinderHelper::CPathfinderHelper(CGameState * gs, const CGHeroInstance * Hero, const PathfinderOptions & Options)
-	: CGameInfoCallback(gs, boost::optional<PlayerColor>()), turn(-1), hero(Hero), options(Options), owner(Hero->tempOwner)
+CPathfinderHelper::CPathfinderHelper(CGameState * gs, const CGHeroInstance * Hero, const PathfinderOptions & Options):
+	CGameInfoCallback(gs, std::optional<PlayerColor>()),
+	turn(-1),
+	hero(Hero),
+	options(Options),
+	owner(Hero->tempOwner)
 {
 	turnsInfo.reserve(16);
 	updateTurnInfo();

lib/CPlayerState.h

@@ -38,7 +38,7 @@ public:
 
 	bool enteredWinningCheatCode, enteredLosingCheatCode; //if true, this player has entered cheat codes for loss / victory
 	EPlayerStatus::EStatus status;
-	boost::optional<ui8> daysWithoutCastle;
+	std::optional<ui8> daysWithoutCastle;
 
 	PlayerState();
 	PlayerState(PlayerState && other) noexcept;

lib/CSkillHandler.cpp

@@ -262,7 +262,7 @@ si32 CSkillHandler::decodeSkill(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeMap(), "skill", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return -1;
 }

lib/CTownHandler.cpp

@@ -1151,7 +1151,7 @@ void CTownHandler::initializeRequirements()
 				logMod->warn("Entry contains: ");
 				logMod->warn(node.toJson());
 			}
-			return BuildingID(VLC->modh->identifiers.getIdentifier(requirement.town->getBuildingScope(), node.Vector()[0]).get());
+			return BuildingID(VLC->modh->identifiers.getIdentifier(requirement.town->getBuildingScope(), node.Vector()[0]).value());
 		});
 	}
 	requirementsToLoad.clear();
@@ -1166,7 +1166,7 @@ void CTownHandler::initializeOverridden()
 
 		for(const auto & b : jsonNode.Vector())
 		{
-			auto bid = BuildingID(VLC->modh->identifiers.getIdentifier(scope, b).get());
+			auto bid = BuildingID(VLC->modh->identifiers.getIdentifier(scope, b).value());
 			bidHelper.building->overrideBids.insert(bid);
 		}
 	}

lib/GameConstants.cpp

@@ -64,7 +64,7 @@ si32 HeroTypeID::decode(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeMap(), "hero", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return -1;
 }
@@ -88,7 +88,7 @@ si32 ArtifactID::decode(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeGame(), "artifact", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return -1;
 }
@@ -112,7 +112,7 @@ si32 CreatureID::decode(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeGame(), "creature", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return -1;
 }
@@ -141,7 +141,7 @@ si32 SpellID::decode(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeGame(), "spell", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return -1;
 }
@@ -204,7 +204,7 @@ si32 FactionID::decode(const std::string & identifier)
 {
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeGame(), "faction", identifier);
 	if(rawId)
-		return rawId.get();
+		return rawId.value();
 	else
 		return FactionID::DEFAULT;
 }
@@ -292,7 +292,7 @@ BattleField BattleField::fromString(const std::string & identifier)
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeBuiltin(), "battlefield", identifier);
 
 	if(rawId)
-		return BattleField(rawId.get());
+		return BattleField(rawId.value());
 	else
 		return BattleField::NONE;
 }
@@ -312,7 +312,7 @@ Obstacle Obstacle::fromString(const std::string & identifier)
 	auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeBuiltin(), "obstacle", identifier);
 
 	if(rawId)
-		return Obstacle(rawId.get());
+		return Obstacle(rawId.value());
 	else
 		return Obstacle(-1);
 }

lib/HeroBonus.cpp

@@ -1520,7 +1520,7 @@ int64_t CBonusSystemNode::getTreeVersion() const
 	return treeChanged;
 }
 
-std::string Bonus::Description(boost::optional<si32> customValue) const
+std::string Bonus::Description(std::optional<si32> customValue) const
 {
 	std::ostringstream str;
 

lib/HeroBonus.h

@@ -533,7 +533,7 @@ struct DLL_LINKAGE Bonus : public std::enable_shared_from_this<Bonus>
 		return sid & 0x0000FFFF;
 	}
 
-	std::string Description(boost::optional<si32> customValue = {}) const;
+	std::string Description(std::optional<si32> customValue = {}) const;
 	JsonNode toJsonNode() const;
 	std::string nameForBonus() const; // generate suitable name for bonus - e.g. for storing in json struct
 

lib/IGameCallback.cpp

@@ -66,7 +66,7 @@ void CPrivilegedInfoCallback::getFreeTiles(std::vector<int3> & tiles) const
 void CPrivilegedInfoCallback::getTilesInRange(std::unordered_set<int3, ShashInt3> & tiles,
 											  const int3 & pos,
 											  int radious,
-											  boost::optional<PlayerColor> player,
+											  std::optional<PlayerColor> player,
 											  int mode,
 											  int3::EDistanceFormula distanceFormula) const
 {
@@ -100,7 +100,7 @@ void CPrivilegedInfoCallback::getTilesInRange(std::unordered_set<int3, ShashInt3
 	}
 }
 
-void CPrivilegedInfoCallback::getAllTiles(std::unordered_set<int3, ShashInt3> & tiles, boost::optional<PlayerColor> Player, int level, MapTerrainFilterMode tileFilterMode) const
+void CPrivilegedInfoCallback::getAllTiles(std::unordered_set<int3, ShashInt3> & tiles, std::optional<PlayerColor> Player, int level, MapTerrainFilterMode tileFilterMode) const
 {
 	if(!!Player && *Player >= PlayerColor::PLAYER_LIMIT)
 	{

lib/IGameCallback.h

@@ -62,12 +62,12 @@ public:
 	void getTilesInRange(std::unordered_set<int3, ShashInt3> & tiles,
 						 const int3 & pos,
 						 int radious,
-						 boost::optional<PlayerColor> player = boost::optional<PlayerColor>(),
+						 std::optional<PlayerColor> player = std::optional<PlayerColor>(),
 						 int mode = 0,
 						 int3::EDistanceFormula formula = int3::DIST_2D) const;
 
 	//returns all tiles on given level (-1 - both levels, otherwise number of level)
-	void getAllTiles(std::unordered_set<int3, ShashInt3> &tiles, boost::optional<PlayerColor> player = boost::optional<PlayerColor>(),
+	void getAllTiles(std::unordered_set<int3, ShashInt3> &tiles, std::optional<PlayerColor> player = std::optional<PlayerColor>(),
 					 int level = -1, MapTerrainFilterMode tileFilterMode = MapTerrainFilterMode::NONE) const;
 
 	//gives 3 treasures, 3 minors, 1 major -> used by Black Market and Artifact Merchant

lib/LogicalExpression.h

@@ -21,7 +21,7 @@ namespace LogicalExpressionDetail
 	class ExpressionBase
 	{
 	public:
-		/// Possible logical operations, mostly needed to create different types for boost::variant
+		/// Possible logical operations, mostly needed to create different types for std::variant
 		enum EOperations
 		{
 			ANY_OF,
@@ -37,7 +37,7 @@ namespace LogicalExpressionDetail
 		typedef ContainedClass Value;
 
 		/// Variant that contains all possible elements from logical expression
-		typedef boost::variant<
+		typedef std::variant<
 			OperatorAll,
 			OperatorAny,
 			OperatorNone,
@@ -70,8 +70,8 @@ namespace LogicalExpressionDetail
 	};
 
 	/// Visitor to test result (true/false) of the expression
-	template <typename ContainedClass>
-	class TestVisitor : public boost::static_visitor<bool>
+	template<typename ContainedClass>
+	class TestVisitor
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -81,7 +81,7 @@ namespace LogicalExpressionDetail
 		{
 			return boost::range::count_if(element, [&](const typename Base::Variant & expr)
 			{
-				return boost::apply_visitor(*this, expr);
+				return std::visit(*this, expr);
 			});
 		}
 	public:
@@ -116,8 +116,8 @@ namespace LogicalExpressionDetail
 	template <typename ContainedClass>
 	class FalsifiabilityVisitor;
 
-	template <typename ContainedClass>
-	class PossibilityVisitor : public boost::static_visitor<bool>
+	template<typename ContainedClass>
+	class PossibilityVisitor
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -131,7 +131,7 @@ namespace LogicalExpressionDetail
 		{
 			return boost::range::count_if(element, [&](const typename Base::Variant & expr)
 			{
-				return boost::apply_visitor(*satisfiabilityVisitor, expr);
+				return std::visit(*satisfiabilityVisitor, expr);
 			});
 		}
 
@@ -139,7 +139,7 @@ namespace LogicalExpressionDetail
 		{
 			return boost::range::count_if(element, [&](const typename Base::Variant & expr)
 			{
-				return boost::apply_visitor(*falsifiabilityVisitor, expr);
+				return std::visit(*falsifiabilityVisitor, expr);
 			});
 		}
 
@@ -235,8 +235,8 @@ namespace LogicalExpressionDetail
 
 	/// visitor that is trying to generates candidates that must be fulfilled
 	/// to complete this expression
-	template <typename ContainedClass>
-	class CandidatesVisitor : public boost::static_visitor<std::vector<ContainedClass> >
+	template<typename ContainedClass>
+	class CandidatesVisitor
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 		typedef std::vector<typename Base::Value> TValueList;
@@ -254,7 +254,7 @@ namespace LogicalExpressionDetail
 			if (!classTest(element))
 			{
 				for (auto & elem : element.expressions)
-					boost::range::copy(boost::apply_visitor(*this, elem), std::back_inserter(ret));
+					boost::range::copy(std::visit(*this, elem), std::back_inserter(ret));
 			}
 			return ret;
 		}
@@ -265,7 +265,7 @@ namespace LogicalExpressionDetail
 			if (!classTest(element))
 			{
 				for (auto & elem : element.expressions)
-					boost::range::copy(boost::apply_visitor(*this, elem), std::back_inserter(ret));
+					boost::range::copy(std::visit(*this, elem), std::back_inserter(ret));
 			}
 			return ret;
 		}
@@ -285,8 +285,8 @@ namespace LogicalExpressionDetail
 	};
 
 	/// Simple foreach visitor
-	template <typename ContainedClass>
-	class ForEachVisitor : public boost::static_visitor<typename ExpressionBase<ContainedClass>::Variant>
+	template<typename ContainedClass>
+	class ForEachVisitor
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -306,14 +306,14 @@ namespace LogicalExpressionDetail
 		typename Base::Variant operator()(Type element) const
 		{
 			for (auto & entry : element.expressions)
-				entry = boost::apply_visitor(*this, entry);
+				entry = std::visit(*this, entry);
 			return element;
 		}
 	};
 
 	/// Minimizing visitor that removes all redundant elements from variant (e.g. AllOf inside another AllOf can be merged safely)
-	template <typename ContainedClass>
-	class MinimizingVisitor : public boost::static_visitor<typename ExpressionBase<ContainedClass>::Variant>
+	template<typename ContainedClass>
+	class MinimizingVisitor
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -330,15 +330,15 @@ namespace LogicalExpressionDetail
 
 			for (auto & entryRO : element.expressions)
 			{
-				auto entry = boost::apply_visitor(*this, entryRO);
+				auto entry = std::visit(*this, entryRO);
 
 				try
 				{
 					// copy entries from child of this type
-					auto sublist = boost::get<Type>(entry).expressions;
+					auto sublist = std::get<Type>(entry).expressions;
 					std::move(sublist.begin(), sublist.end(), std::back_inserter(ret.expressions));
 				}
-				catch (boost::bad_get &)
+				catch (std::bad_variant_access &)
 				{
 					// different type (e.g. allOf vs oneOf) just copy
 					ret.expressions.push_back(entry);
@@ -397,8 +397,8 @@ namespace LogicalExpressionDetail
 	};
 
 	/// Serializes expression in JSON format. Part of map format.
-	template <typename ContainedClass>
-	class Writer : public boost::static_visitor<JsonNode>
+	template<typename ContainedClass>
+	class Writer
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -410,7 +410,7 @@ namespace LogicalExpressionDetail
 			ret.Vector().resize(1);
 			ret.Vector().back().String() = name;
 			for (auto & expr : element)
-				ret.Vector().push_back(boost::apply_visitor(*this, expr));
+				ret.Vector().push_back(std::visit(*this, expr));
 			return ret;
 		}
 	public:
@@ -442,8 +442,8 @@ namespace LogicalExpressionDetail
 	std::string DLL_LINKAGE getTextForOperator(const std::string & operation);
 
 	/// Prints expression in human-readable format
-	template <typename ContainedClass>
-	class Printer : public boost::static_visitor<std::string>
+	template<typename ContainedClass>
+	class Printer
 	{
 		typedef ExpressionBase<ContainedClass> Base;
 
@@ -465,7 +465,7 @@ namespace LogicalExpressionDetail
 			std::string ret;
 			prefix.push_back('\t');
 			for (auto & expr : element)
-				ret += prefix + boost::apply_visitor(*this, expr) + "\n";
+				ret += prefix + std::visit(*this, expr) + "\n";
 			prefix.pop_back();
 			return ret;
 		}
@@ -552,14 +552,14 @@ public:
 	Variant morph(std::function<Variant(const Value &)> morpher) const
 	{
 		LogicalExpressionDetail::ForEachVisitor<Value> visitor(morpher);
-		return boost::apply_visitor(visitor, data);
+		return std::visit(visitor, data);
 	}
 
 	/// Minimizes expression, removing any redundant elements
 	void minimize()
 	{
 		LogicalExpressionDetail::MinimizingVisitor<Value> visitor;
-		data = boost::apply_visitor(visitor, data);
+		data = std::visit(visitor, data);
 	}
 
 	/// calculates if expression evaluates to "true".
@@ -567,7 +567,7 @@ public:
 	bool test(std::function<bool(const Value &)> toBool) const
 	{
 		LogicalExpressionDetail::TestVisitor<Value> testVisitor(toBool);
-		return boost::apply_visitor(testVisitor, data);
+		return std::visit(testVisitor, data);
 	}
 
 	/// calculates if expression can evaluate to "true".
@@ -579,7 +579,7 @@ public:
 		satisfiabilityVisitor.setFalsifiabilityVisitor(&falsifiabilityVisitor);
 		falsifiabilityVisitor.setSatisfiabilityVisitor(&satisfiabilityVisitor);
 
-		return boost::apply_visitor(satisfiabilityVisitor, data);
+		return std::visit(satisfiabilityVisitor, data);
 	}
 
 	/// calculates if expression can evaluate to "false".
@@ -591,14 +591,14 @@ public:
 		satisfiabilityVisitor.setFalsifiabilityVisitor(&falsifiabilityVisitor);
 		falsifiabilityVisitor.setFalsifiabilityVisitor(&satisfiabilityVisitor);
 
-		return boost::apply_visitor(falsifiabilityVisitor, data);
+		return std::visit(falsifiabilityVisitor, data);
 	}
 
 	/// generates list of candidates that can be fulfilled by caller (like AI)
 	std::vector<Value> getFulfillmentCandidates(std::function<bool(const Value &)> toBool) const
 	{
 		LogicalExpressionDetail::CandidatesVisitor<Value> candidateVisitor(toBool);
-		return boost::apply_visitor(candidateVisitor, data);
+		return std::visit(candidateVisitor, data);
 	}
 
 	/// Converts expression in human-readable form
@@ -607,18 +607,18 @@ public:
 	std::string toString(std::function<std::string(const Value &)> toStr) const
 	{
 		LogicalExpressionDetail::Printer<Value> printVisitor(toStr);
-		return boost::apply_visitor(printVisitor, data);
+		return std::visit(printVisitor, data);
 	}
 	std::string toString(std::function<std::string(const Value &)> toStr, std::function<bool(const Value &)> toBool) const
 	{
 		LogicalExpressionDetail::Printer<Value> printVisitor(toStr, toBool);
-		return boost::apply_visitor(printVisitor, data);
+		return std::visit(printVisitor, data);
 	}
 
 	JsonNode toJson(std::function<JsonNode(const Value &)> toJson) const
 	{
 		LogicalExpressionDetail::Writer<Value> writeVisitor(toJson);
-		return boost::apply_visitor(writeVisitor, data);
+		return std::visit(writeVisitor, data);
 	}
 
 	template <typename Handler>

lib/NetPacks.h

@@ -145,7 +145,7 @@ struct DLL_LINKAGE YourTurn : public CPackForClient
 	void applyGs(CGameState * gs) const;
 
 	PlayerColor player;
-	boost::optional<ui8> daysWithoutCastle;
+	std::optional<ui8> daysWithoutCastle;
 
 	virtual void visitTyped(ICPackVisitor & visitor) override;
 
@@ -591,7 +591,7 @@ struct DLL_LINKAGE TryMoveHero : public CPackForClient
 	EResult result = FAILED; //uses EResult
 	int3 start, end; //h3m format
 	std::unordered_set<int3, ShashInt3> fowRevealed; //revealed tiles
-	boost::optional<int3> attackedFrom; // Set when stepping into endangered tile.
+	std::optional<int3> attackedFrom; // Set when stepping into endangered tile.
 
 	virtual void visitTyped(ICPackVisitor & visitor) override;
 
@@ -930,17 +930,17 @@ struct DLL_LINKAGE BulkSmartRebalanceStacks : CGarrisonOperationPack
 	}
 };
 
-struct GetEngagedHeroIds : boost::static_visitor<boost::optional<ObjectInstanceID>>
+struct GetEngagedHeroIds
 {
-	boost::optional<ObjectInstanceID> operator()(const ConstTransitivePtr<CGHeroInstance> & h) const
+	std::optional<ObjectInstanceID> operator()(const ConstTransitivePtr<CGHeroInstance> & h) const
 	{
 		return h->id;
 	}
-	boost::optional<ObjectInstanceID> operator()(const ConstTransitivePtr<CStackInstance> & s) const
+	std::optional<ObjectInstanceID> operator()(const ConstTransitivePtr<CStackInstance> & s) const
 	{
 		if(s->armyObj && s->armyObj->ID == Obj::HERO)
 			return s->armyObj->id;
-		return boost::optional<ObjectInstanceID>();
+		return std::optional<ObjectInstanceID>();
 	}
 };
 

lib/NetPacksBase.h

@@ -233,7 +233,7 @@ struct Component
 	}
 };
 
-using TArtHolder = boost::variant<ConstTransitivePtr<CGHeroInstance>, ConstTransitivePtr<CStackInstance>>;
+using TArtHolder = std::variant<ConstTransitivePtr<CGHeroInstance>, ConstTransitivePtr<CStackInstance>>;
 
 struct ArtifactLocation
 {
@@ -259,9 +259,9 @@ struct ArtifactLocation
 	template <typename T>
 	bool isHolder(const T *t) const
 	{
-		if(auto ptrToT = boost::get<ConstTransitivePtr<T> >(&artHolder))
+		if(auto ptrToT = std::get<ConstTransitivePtr<T>>(artHolder))
 		{
-			return ptrToT->get() == t;
+			return ptrToT == t;
 		}
 		return false;
 	}

lib/NetPacksLib.cpp

@@ -1532,7 +1532,7 @@ const CStackInstance * StackLocation::getStack()
 	return &army->getStack(slot);
 }
 
-struct ObjectRetriever : boost::static_visitor<const CArmedInstance *>
+struct ObjectRetriever
 {
 	const CArmedInstance * operator()(const ConstTransitivePtr<CGHeroInstance> &h) const
 	{
@@ -1543,8 +1543,8 @@ struct ObjectRetriever : boost::static_visitor<const CArmedInstance *>
 		return s->armyObj;
 	}
 };
-template <typename T>
-struct GetBase : boost::static_visitor<T*>
+template<typename T>
+struct GetBase
 {
 	template <typename TArg>
 	T * operator()(TArg &arg) const
@@ -1563,7 +1563,7 @@ void ArtifactLocation::removeArtifact()
 
 const CArmedInstance * ArtifactLocation::relatedObj() const
 {
-	return boost::apply_visitor(ObjectRetriever(), artHolder);
+	return std::visit(ObjectRetriever(), artHolder);
 }
 
 PlayerColor ArtifactLocation::owningPlayer() const
@@ -1574,12 +1574,12 @@ PlayerColor ArtifactLocation::owningPlayer() const
 
 CArtifactSet *ArtifactLocation::getHolderArtSet()
 {
-	return boost::apply_visitor(GetBase<CArtifactSet>(), artHolder);
+	return std::visit(GetBase<CArtifactSet>(), artHolder);
 }
 
 CBonusSystemNode *ArtifactLocation::getHolderNode()
 {
-	return boost::apply_visitor(GetBase<CBonusSystemNode>(), artHolder);
+	return std::visit(GetBase<CBonusSystemNode>(), artHolder);
 }
 
 const CArtifactInstance *ArtifactLocation::getArt() const
@@ -2050,11 +2050,11 @@ void NewTurn::applyGs(CGameState *gs)
 				if (playerState.daysWithoutCastle)
 					++(*playerState.daysWithoutCastle);
 				else
-					playerState.daysWithoutCastle = boost::make_optional(0);
+					playerState.daysWithoutCastle = std::make_optional(0);
 			}
 			else
 			{
-				playerState.daysWithoutCastle = boost::none;
+				playerState.daysWithoutCastle = std::nullopt;
 			}
 		}
 	}
@@ -2085,7 +2085,7 @@ void SetObjectProperty::applyGs(CGameState * gs) const
 
 				//reset counter before NewTurn to avoid no town message if game loaded at turn when one already captured
 				if(p->daysWithoutCastle)
-					p->daysWithoutCastle = boost::none;
+					p->daysWithoutCastle = std::nullopt;
 			}
 		}
 
@@ -2533,12 +2533,12 @@ const CArtifactInstance * ArtSlotInfo::getArt() const
 
 CArtifactSet * BulkMoveArtifacts::getSrcHolderArtSet()
 {
-	return boost::apply_visitor(GetBase<CArtifactSet>(), srcArtHolder);
+	return std::visit(GetBase<CArtifactSet>(), srcArtHolder);
 }
 
 CArtifactSet * BulkMoveArtifacts::getDstHolderArtSet()
 {
-	return boost::apply_visitor(GetBase<CArtifactSet>(), dstArtHolder);
+	return std::visit(GetBase<CArtifactSet>(), dstArtHolder);
 }
 
 VCMI_LIB_NAMESPACE_END

lib/battle/BattleHex.h

@@ -29,7 +29,7 @@ namespace GameConstants
 	const int BFIELD_SIZE = BFIELD_WIDTH * BFIELD_HEIGHT;
 }
 
-using BattleSideOpt =  boost::optional<ui8>;
+using BattleSideOpt = std::optional<ui8>;
 
 // for battle stacks' positions
 struct DLL_LINKAGE BattleHex //TODO: decide if this should be changed to class for better code design

lib/battle/CBattleInfoCallback.cpp

@@ -106,7 +106,7 @@ ESpellCastProblem::ESpellCastProblem CBattleInfoCallback::battleCanCastSpell(con
 	const auto side = playerToSide(player);
 	if(!side)
 		return ESpellCastProblem::INVALID;
-	if(!battleDoWeKnowAbout(side.get()))
+	if(!battleDoWeKnowAbout(side.value()))
 	{
 		logGlobal->warn("You can't check if enemy can cast given spell!");
 		return ESpellCastProblem::INVALID;
@@ -119,7 +119,7 @@ ESpellCastProblem::ESpellCastProblem CBattleInfoCallback::battleCanCastSpell(con
 	{
 	case spells::Mode::HERO:
 	{
-		if(battleCastSpells(side.get()) > 0)
+		if(battleCastSpells(side.value()) > 0)
 			return ESpellCastProblem::CASTS_PER_TURN_LIMIT;
 
 		const auto * hero = dynamic_cast<const CGHeroInstance *>(caster);
@@ -229,7 +229,7 @@ std::vector<PossiblePlayerBattleAction> CBattleInfoCallback::getClientActionsFor
 		{
 			if(stack->hasBonusOfType(Bonus::SPELLCASTER))
 			{
-				for (auto const & spellID : data.creatureSpellsToCast)
+				for(const auto & spellID : data.creatureSpellsToCast)
 				{
 					const CSpell *spell = spellID.toSpell();
 					PossiblePlayerBattleAction act = getCasterAction(spell, stack, spells::Mode::CREATURE_ACTIVE);
@@ -767,7 +767,7 @@ DamageEstimation CBattleInfoCallback::battleEstimateDamage(const BattleAttackInf
 			//TODO: rewrite using boost::numeric::interval
 			//TODO: rewire once more using interval-based fuzzy arithmetic
 
-			auto const & estimateRetaliation = [&]( int64_t damage)
+			const auto & estimateRetaliation = [&](int64_t damage)
 			{
 				auto retaliationAttack = bai.reverse();
 				auto state = retaliationAttack.attacker->acquireState();
@@ -1763,7 +1763,7 @@ int CBattleInfoCallback::battleGetSurrenderCost(const PlayerColor & Player) cons
 	const auto sideOpt = playerToSide(Player);
 	if(!sideOpt)
 		return -1;
-	const auto side = sideOpt.get();
+	const auto side = sideOpt.value();
 
 	int ret = 0;
 	double discount = 0;
@@ -1816,7 +1816,7 @@ si8 CBattleInfoCallback::battleMaxSpellLevel(ui8 side) const
 	return GameConstants::SPELL_LEVELS;
 }
 
-boost::optional<int> CBattleInfoCallback::battleIsFinished() const
+std::optional<int> CBattleInfoCallback::battleIsFinished() const
 {
 	auto units = battleGetUnitsIf([=](const battle::Unit * unit)
 	{
@@ -1831,7 +1831,7 @@ boost::optional<int> CBattleInfoCallback::battleIsFinished() const
 		hasUnit.at(unit->unitSide()) = true;
 
 		if(hasUnit[0] && hasUnit[1])
-			return boost::none;
+			return std::nullopt;
 	}
 	
 	hasUnit = {false, false};

lib/battle/CBattleInfoCallback.h

@@ -58,7 +58,7 @@ public:
 		RANDOM_GENIE, RANDOM_AIMED
 	};
 
-	boost::optional<int> battleIsFinished() const override; //return none if battle is ongoing; otherwise the victorious side (0/1) or 2 if it is a draw
+	std::optional<int> battleIsFinished() const override; //return none if battle is ongoing; otherwise the victorious side (0/1) or 2 if it is a draw
 
 	std::vector<std::shared_ptr<const CObstacleInstance>> battleGetAllObstaclesOnPos(BattleHex tile, bool onlyBlocking = true) const override;
 	std::vector<std::shared_ptr<const CObstacleInstance>> getAllAffectedObstaclesByStack(const battle::Unit * unit, const std::set<BattleHex> & passed) const override;

lib/battle/CBattleInfoEssentials.cpp

@@ -34,7 +34,7 @@ int32_t CBattleInfoEssentials::battleGetEnchanterCounter(ui8 side) const
 	return getBattle()->getEnchanterCounter(side);
 }
 
-std::vector<std::shared_ptr<const CObstacleInstance>> CBattleInfoEssentials::battleGetAllObstacles(boost::optional<BattlePerspective::BattlePerspective> perspective) const
+std::vector<std::shared_ptr<const CObstacleInstance>> CBattleInfoEssentials::battleGetAllObstacles(std::optional<BattlePerspective::BattlePerspective> perspective) const
 {
 	std::vector<std::shared_ptr<const CObstacleInstance> > ret;
 	RETURN_IF_NOT_BATTLE(ret);
@@ -42,7 +42,7 @@ std::vector<std::shared_ptr<const CObstacleInstance>> CBattleInfoEssentials::bat
 	if(!perspective)
 	{
 		//if no particular perspective request, use default one
-		perspective = boost::make_optional(battleGetMySide());
+		perspective = std::make_optional(battleGetMySide());
 	}
 	else
 	{
@@ -156,7 +156,7 @@ const CGTownInstance * CBattleInfoEssentials::battleGetDefendedTown() const
 BattlePerspective::BattlePerspective CBattleInfoEssentials::battleGetMySide() const
 {
 	RETURN_IF_NOT_BATTLE(BattlePerspective::INVALID);
-	if(!player || player.get().isSpectator())
+	if(!player || player->isSpectator())
 		return BattlePerspective::ALL_KNOWING;
 	if(*player == getBattle()->getSidePlayer(BattleSide::ATTACKER))
 		return BattlePerspective::LEFT_SIDE;
@@ -264,7 +264,7 @@ bool CBattleInfoEssentials::battleCanFlee(const PlayerColor & player) const
 	if(!side)
 		return false;
 
-	const CGHeroInstance *myHero = battleGetFightingHero(side.get());
+	const CGHeroInstance * myHero = battleGetFightingHero(side.value());
 
 	//current player have no hero
 	if(!myHero)
@@ -275,7 +275,7 @@ bool CBattleInfoEssentials::battleCanFlee(const PlayerColor & player) const
 		return false;
 
 	//we are besieged defender
-	if(side.get() == BattleSide::DEFENDER && battleGetSiegeLevel())
+	if(side == BattleSide::DEFENDER && battleGetSiegeLevel())
 	{
 		const auto * town = battleGetDefendedTown();
 		if(!town->hasBuilt(BuildingSubID::ESCAPE_TUNNEL))
@@ -287,7 +287,7 @@ bool CBattleInfoEssentials::battleCanFlee(const PlayerColor & player) const
 
 BattleSideOpt CBattleInfoEssentials::playerToSide(const PlayerColor & player) const
 {
-	RETURN_IF_NOT_BATTLE(boost::none);
+	RETURN_IF_NOT_BATTLE(std::nullopt);
 
 	if(getBattle()->getSidePlayer(BattleSide::ATTACKER) == player)
 		return BattleSideOpt(BattleSide::ATTACKER);
@@ -297,7 +297,7 @@ BattleSideOpt CBattleInfoEssentials::playerToSide(const PlayerColor & player) co
 
 	logGlobal->warn("Cannot find side for player %s", player.getStr());
 
-	return boost::none;
+	return std::nullopt;
 }
 
 PlayerColor CBattleInfoEssentials::sideToPlayer(ui8 side) const
@@ -322,7 +322,7 @@ PlayerColor CBattleInfoEssentials::otherPlayer(const PlayerColor & player) const
     if(!side)
 		return PlayerColor::CANNOT_DETERMINE;
 
-	return getBattle()->getSidePlayer(otherSide(side.get()));
+	return getBattle()->getSidePlayer(otherSide(side.value()));
 }
 
 bool CBattleInfoEssentials::playerHasAccessToHeroInfo(const PlayerColor & player, const CGHeroInstance * h) const
@@ -331,7 +331,7 @@ bool CBattleInfoEssentials::playerHasAccessToHeroInfo(const PlayerColor & player
 	const auto side = playerToSide(player);
 	if(side)
 	{
-		auto opponentSide = otherSide(side.get());
+		auto opponentSide = otherSide(side.value());
 		if(getBattle()->getSideHero(opponentSide) == h)
 			return true;
 	}
@@ -350,9 +350,9 @@ bool CBattleInfoEssentials::battleCanSurrender(const PlayerColor & player) const
 	const auto side = playerToSide(player);
 	if(!side)
 		return false;
-	bool iAmSiegeDefender = (side.get() == BattleSide::DEFENDER && battleGetSiegeLevel());
+	bool iAmSiegeDefender = (side.value() == BattleSide::DEFENDER && battleGetSiegeLevel());
 	//conditions like for fleeing (except escape tunnel presence) + enemy must have a hero
-	return battleCanFlee(player) && !iAmSiegeDefender && battleHasHero(otherSide(side.get()));
+	return battleCanFlee(player) && !iAmSiegeDefender && battleHasHero(otherSide(side.value()));
 }
 
 bool CBattleInfoEssentials::battleHasHero(ui8 side) const
@@ -409,7 +409,7 @@ const CGHeroInstance * CBattleInfoEssentials::battleGetOwnerHero(const battle::U
 	const auto side = playerToSide(battleGetOwner(unit));
 	if(!side)
 		return nullptr;
-	return getBattle()->getSideHero(side.get());
+	return getBattle()->getSideHero(side.value());
 }
 
 bool CBattleInfoEssentials::battleMatchOwner(const battle::Unit * attacker, const battle::Unit * defender, const boost::logic::tribool positivness) const

lib/battle/CBattleInfoEssentials.h

@@ -52,7 +52,7 @@ public:
 	BattleField battleGetBattlefieldType() const override;
 	int32_t battleGetEnchanterCounter(ui8 side) const;
 
-	std::vector<std::shared_ptr<const CObstacleInstance> > battleGetAllObstacles(boost::optional<BattlePerspective::BattlePerspective> perspective = boost::none) const; //returns all obstacles on the battlefield
+	std::vector<std::shared_ptr<const CObstacleInstance> > battleGetAllObstacles(std::optional<BattlePerspective::BattlePerspective> perspective = std::nullopt) const; //returns all obstacles on the battlefield
 
 	std::shared_ptr<const CObstacleInstance> battleGetObstacleByID(uint32_t ID) const;
 

lib/battle/CCallbackBase.cpp

@@ -23,7 +23,7 @@ const IBattleInfo * CCallbackBase::getBattle() const
 	return battle;
 }
 
-CCallbackBase::CCallbackBase(boost::optional<PlayerColor> Player):
+CCallbackBase::CCallbackBase(std::optional<PlayerColor> Player):
 	player(std::move(Player))
 {
 }
@@ -33,7 +33,7 @@ void CCallbackBase::setBattle(const IBattleInfo * B)
 	battle = B;
 }
 
-boost::optional<PlayerColor> CCallbackBase::getPlayerID() const
+std::optional<PlayerColor> CCallbackBase::getPlayerID() const
 {
 	return player;
 }

lib/battle/CCallbackBase.h

@@ -26,9 +26,9 @@ class DLL_LINKAGE CCallbackBase
 	const IBattleInfo * battle = nullptr; //battle to which the player is engaged, nullptr if none or not applicable
 
 protected:
-	boost::optional<PlayerColor> player; // not set gives access to all information, otherwise callback provides only information "visible" for player
+	std::optional<PlayerColor> player; // not set gives access to all information, otherwise callback provides only information "visible" for player
 
-	CCallbackBase(boost::optional<PlayerColor> Player);
+	CCallbackBase(std::optional<PlayerColor> Player);
 	CCallbackBase() = default;
 
 	const IBattleInfo * getBattle() const;
@@ -36,7 +36,7 @@ protected:
 	bool duringBattle() const;
 
 public:
-	boost::optional<PlayerColor> getPlayerID() const;
+	std::optional<PlayerColor> getPlayerID() const;
 
 	friend class CBattleInfoEssentials;
 };

lib/battle/IBattleInfoCallback.h

@@ -58,7 +58,7 @@ public:
 	virtual BattleField battleGetBattlefieldType() const = 0;
 
 	///return none if battle is ongoing; otherwise the victorious side (0/1) or 2 if it is a draw
-	virtual boost::optional<int> battleIsFinished() const = 0;
+	virtual std::optional<int> battleIsFinished() const = 0;
 
 	virtual si8 battleTacticDist() const = 0; //returns tactic distance in current tactics phase; 0 if not in tactics phase
 	virtual si8 battleGetTacticsSide() const = 0; //returns which side is in tactics phase, undefined if none (?)

lib/filesystem/AdapterLoaders.cpp

@@ -39,7 +39,7 @@ std::string CMappedFileLoader::getMountPoint() const
 	return ""; // does not have any meaning with this type of data source
 }
 
-boost::optional<boost::filesystem::path> CMappedFileLoader::getResourceName(const ResourceID & resourceName) const
+std::optional<boost::filesystem::path> CMappedFileLoader::getResourceName(const ResourceID & resourceName) const
 {
 	return CResourceHandler::get()->getResourceName(fileList.at(resourceName));
 }
@@ -90,11 +90,11 @@ std::string CFilesystemList::getMountPoint() const
 	return "";
 }
 
-boost::optional<boost::filesystem::path> CFilesystemList::getResourceName(const ResourceID & resourceName) const
+std::optional<boost::filesystem::path> CFilesystemList::getResourceName(const ResourceID & resourceName) const
 {
 	if (existsResource(resourceName))
 		return getResourcesWithName(resourceName).back()->getResourceName(resourceName);
-	return boost::optional<boost::filesystem::path>();
+	return std::optional<boost::filesystem::path>();
 }
 
 std::set<boost::filesystem::path> CFilesystemList::getResourceNames(const ResourceID & resourceName) const

lib/filesystem/AdapterLoaders.h

@@ -41,7 +41,7 @@ public:
 	std::unique_ptr<CInputStream> load(const ResourceID & resourceName) const override;
 	bool existsResource(const ResourceID & resourceName) const override;
 	std::string getMountPoint() const override;
-	boost::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
+	std::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
 	void updateFilteredFiles(std::function<bool(const std::string &)> filter) const override {}
 	std::unordered_set<ResourceID> getFilteredFiles(std::function<bool(const ResourceID &)> filter) const override;
 
@@ -71,7 +71,7 @@ public:
 	std::unique_ptr<CInputStream> load(const ResourceID & resourceName) const override;
 	bool existsResource(const ResourceID & resourceName) const override;
 	std::string getMountPoint() const override;
-	boost::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
+	std::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
 	std::set<boost::filesystem::path> getResourceNames(const ResourceID & resourceName) const override;
 	void updateFilteredFiles(std::function<bool(const std::string &)> filter) const override;
 	std::unordered_set<ResourceID> getFilteredFiles(std::function<bool(const ResourceID &)> filter) const override;

lib/filesystem/CFilesystemLoader.cpp

@@ -44,7 +44,7 @@ std::string CFilesystemLoader::getMountPoint() const
 	return mountPoint;
 }
 
-boost::optional<boost::filesystem::path> CFilesystemLoader::getResourceName(const ResourceID & resourceName) const
+std::optional<boost::filesystem::path> CFilesystemLoader::getResourceName(const ResourceID & resourceName) const
 {
 	assert(existsResource(resourceName));
 

lib/filesystem/CFilesystemLoader.h

@@ -38,7 +38,7 @@ public:
 	bool existsResource(const ResourceID & resourceName) const override;
 	std::string getMountPoint() const override;
 	bool createResource(std::string filename, bool update = false) override;
-	boost::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
+	std::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const override;
 	void updateFilteredFiles(std::function<bool(const std::string &)> filter) const override;
 	std::unordered_set<ResourceID> getFilteredFiles(std::function<bool(const ResourceID &)> filter) const override;
 

lib/filesystem/ISimpleResourceLoader.h

@@ -49,9 +49,9 @@ public:
 	 *
 	 * @return path or empty optional if file can't be accessed independently (e.g. file in archive)
 	 */
-	virtual boost::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const
+	virtual std::optional<boost::filesystem::path> getResourceName(const ResourceID & resourceName) const
 	{
-		return boost::optional<boost::filesystem::path>();
+		return std::optional<boost::filesystem::path>();
 	}
 
 	/**

lib/mapObjects/CArmedInstance.cpp

@@ -29,7 +29,7 @@ void CArmedInstance::randomizeArmy(int type)
 			int upgrade = elem.second->randomStack->upgrade;
 			elem.second->setType((*VLC->townh)[type]->town->creatures[level][upgrade]);
 
-			elem.second->randomStack = boost::none;
+			elem.second->randomStack = std::nullopt;
 		}
 		assert(elem.second->valid(false));
 		assert(elem.second->armyObj == this);

lib/mapObjects/CGHeroInstance.cpp

@@ -1280,11 +1280,11 @@ PrimarySkill::PrimarySkill CGHeroInstance::nextPrimarySkill(CRandomGenerator & r
 	return static_cast<PrimarySkill::PrimarySkill>(primarySkill);
 }
 
-boost::optional<SecondarySkill> CGHeroInstance::nextSecondarySkill(CRandomGenerator & rand) const
+std::optional<SecondarySkill> CGHeroInstance::nextSecondarySkill(CRandomGenerator & rand) const
 {
 	assert(gainsLevel());
 
-	boost::optional<SecondarySkill> chosenSecondarySkill;
+	std::optional<SecondarySkill> chosenSecondarySkill;
 	const auto proposedSecondarySkills = getLevelUpProposedSecondarySkills();
 	if(!proposedSecondarySkills.empty())
 	{
@@ -1300,12 +1300,12 @@ boost::optional<SecondarySkill> CGHeroInstance::nextSecondarySkill(CRandomGenera
 		if(learnedSecondarySkills.empty())
 		{
 			// there are only new skills to learn, so choose anyone of them
-			chosenSecondarySkill = boost::make_optional(*RandomGeneratorUtil::nextItem(proposedSecondarySkills, rand));
+			chosenSecondarySkill = std::make_optional(*RandomGeneratorUtil::nextItem(proposedSecondarySkills, rand));
 		}
 		else
 		{
 			// preferably upgrade a already learned secondary skill
-			chosenSecondarySkill = boost::make_optional(*RandomGeneratorUtil::nextItem(learnedSecondarySkills, rand));
+			chosenSecondarySkill = std::make_optional(*RandomGeneratorUtil::nextItem(learnedSecondarySkills, rand));
 		}
 	}
 	return chosenSecondarySkill;
@@ -1441,7 +1441,7 @@ void CGHeroInstance::setHeroTypeName(const std::string & identifier)
 		auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeMap(), "hero", identifier);
 
 		if(rawId)
-			subID = rawId.get();
+			subID = rawId.value();
 		else
 		{
 			throw std::runtime_error("Couldn't resolve hero identifier " + identifier);

lib/mapObjects/CGHeroInstance.h

@@ -182,7 +182,7 @@ public:
 	PrimarySkill::PrimarySkill nextPrimarySkill(CRandomGenerator & rand) const;
 
 	/// Returns the next secondary skill randomly on level up. Can only be called if hero can gain a level up.
-	boost::optional<SecondarySkill> nextSecondarySkill(CRandomGenerator & rand) const;
+	std::optional<SecondarySkill> nextSecondarySkill(CRandomGenerator & rand) const;
 
 	/// Gets 0, 1 or 2 secondary skills which are proposed on hero level up.
 	std::vector<SecondarySkill> getLevelUpProposedSecondarySkills() const;

lib/mapObjects/CGTownInstance.cpp

@@ -1507,7 +1507,7 @@ void CGTownInstance::serializeJsonOptions(JsonSerializeFormat & handler)
 			auto rawId = VLC->modh->identifiers.getIdentifier(CModHandler::scopeMap(), getTown()->getBuildingScope(), identifier);
 
 			if(rawId)
-				return rawId.get();
+				return rawId.value();
 			else
 				return -1;
 		};

lib/mapObjects/CObjectClassesHandler.cpp

@@ -165,7 +165,7 @@ void CObjectClassesHandler::loadSubObject(const std::string & scope, const std::
 	obj->objects.push_back(object);
 
 	registerObject(scope, obj->getJsonKey(), object->getSubTypeName(), object->subtype);
-	for (auto const & compatID : entry["compatibilityIdentifiers"].Vector())
+	for(const auto & compatID : entry["compatibilityIdentifiers"].Vector())
 		registerObject(scope, obj->getJsonKey(), compatID.String(), object->subtype);
 }
 
@@ -178,7 +178,7 @@ void CObjectClassesHandler::loadSubObject(const std::string & scope, const std::
 	obj->objects[index] = object;
 
 	registerObject(scope, obj->getJsonKey(), object->getSubTypeName(), object->subtype);
-	for (auto const & compatID : entry["compatibilityIdentifiers"].Vector())
+	for(const auto & compatID : entry["compatibilityIdentifiers"].Vector())
 		registerObject(scope, obj->getJsonKey(), compatID.String(), object->subtype);
 }
 
@@ -313,14 +313,14 @@ TObjectTypeHandler CObjectClassesHandler::getHandlerFor(si32 type, si32 subtype)
 
 TObjectTypeHandler CObjectClassesHandler::getHandlerFor(const std::string & scope, const std::string & type, const std::string & subtype) const
 {
-	boost::optional<si32> id = VLC->modh->identifiers.getIdentifier(scope, "object", type);
+	std::optional<si32> id = VLC->modh->identifiers.getIdentifier(scope, "object", type);
 	if(id)
 	{
-		auto * object = objects[id.get()];
-		boost::optional<si32> subID = VLC->modh->identifiers.getIdentifier(scope, object->getJsonKey(), subtype);
+		auto * object = objects[id.value()];
+		std::optional<si32> subID = VLC->modh->identifiers.getIdentifier(scope, object->getJsonKey(), subtype);
 
 		if (subID)
-			return object->objects[subID.get()];
+			return object->objects[subID.value()];
 	}
 
 	std::string errorString = "Failed to find object of type " + type + "::" + subtype;
@@ -515,7 +515,7 @@ void AObjectTypeHandler::init(const JsonNode & input)
 
 		const JsonNode & mapLimit = input["rmg"]["mapLimit"];
 		if (!mapLimit.isNull())
-			rmgInfo.mapLimit.reset(static_cast<ui32>(mapLimit.Float()));
+			rmgInfo.mapLimit = static_cast<ui32>(mapLimit.Float());
 
 		rmgInfo.zoneLimit = loadJsonOrMax(input["rmg"]["zoneLimit"]);
 		rmgInfo.rarity =    static_cast<ui32>(input["rmg"]["rarity"].Float());
@@ -551,14 +551,14 @@ void AObjectTypeHandler::init(const JsonNode & input)
 		sounds.removal.push_back(node.String());
 
 	if(input["aiValue"].isNull())
-		aiValue = boost::none;
+		aiValue = std::nullopt;
 	else
-		aiValue = static_cast<boost::optional<si32>>(input["aiValue"].Integer());
+		aiValue = static_cast<std::optional<si32>>(input["aiValue"].Integer());
 
 	if(input["battleground"].getType() == JsonNode::JsonType::DATA_STRING)
 		battlefield = input["battleground"].String();
 	else
-		battlefield = boost::none;
+		battlefield = std::nullopt;
 
 	initTypeData(input);
 }
@@ -625,7 +625,7 @@ std::vector<std::shared_ptr<const ObjectTemplate>> AObjectTypeHandler::getTempla
 
 BattleField AObjectTypeHandler::getBattlefield() const
 {
-	return battlefield ? BattleField::fromString(battlefield.get()) : BattleField::NONE;
+	return battlefield ? BattleField::fromString(battlefield.value()) : BattleField::NONE;
 }
 
 std::vector<std::shared_ptr<const ObjectTemplate>>AObjectTypeHandler::getTemplates(TerrainId terrainType) const
@@ -661,7 +661,7 @@ const RandomMapInfo & AObjectTypeHandler::getRMGInfo()
 	return rmgInfo;
 }
 
-boost::optional<si32> AObjectTypeHandler::getAiValue() const
+std::optional<si32> AObjectTypeHandler::getAiValue() const
 {
 	return aiValue;
 }

lib/mapObjects/CObjectClassesHandler.h

@@ -43,7 +43,7 @@ struct DLL_LINKAGE RandomMapInfo
 	ui32 value;
 
 	/// How many of such objects can be placed on map, 0 = object can not be placed by RMG
-	boost::optional<ui32> mapLimit;
+	std::optional<ui32> mapLimit;
 
 	/// How many of such objects can be placed in one zone, 0 = unplaceable
 	ui32 zoneLimit;
@@ -57,7 +57,7 @@ struct DLL_LINKAGE RandomMapInfo
 		rarity(0)
 	{}
 
-	void setMapLimit(ui32 val) { mapLimit.reset(val); }
+	void setMapLimit(ui32 val) { mapLimit = val; }
 
 	template <typename Handler> void serialize(Handler &h, const int version)
 	{
@@ -150,8 +150,8 @@ class DLL_LINKAGE AObjectTypeHandler : public boost::noncopyable
 
 	SObjectSounds sounds;
 
-	boost::optional<si32> aiValue;
-	boost::optional<std::string> battlefield;
+	std::optional<si32> aiValue;
+	std::optional<std::string> battlefield;
 
 	std::string modScope;
 	std::string typeName;
@@ -200,7 +200,7 @@ public:
 
 	const RandomMapInfo & getRMGInfo();
 
-	boost::optional<si32> getAiValue() const;
+	std::optional<si32> getAiValue() const;
 
 	/// returns true if this class provides custom text ID's instead of generic per-object name
 	virtual bool hasNameTextID() const;

lib/mapObjects/CObjectHandler.cpp

@@ -288,31 +288,31 @@ std::string CGObjectInstance::getObjectName() const
 	return VLC->objtypeh->getObjectName(ID, subID);
 }
 
-boost::optional<std::string> CGObjectInstance::getAmbientSound() const
+std::optional<std::string> CGObjectInstance::getAmbientSound() const
 {
 	const auto & sounds = VLC->objtypeh->getObjectSounds(ID, subID).ambient;
 	if(!sounds.empty())
 		return sounds.front(); // TODO: Support randomization of ambient sounds
 
-	return boost::none;
+	return std::nullopt;
 }
 
-boost::optional<std::string> CGObjectInstance::getVisitSound() const
+std::optional<std::string> CGObjectInstance::getVisitSound() const
 {
 	const auto & sounds = VLC->objtypeh->getObjectSounds(ID, subID).visit;
 	if(!sounds.empty())
 		return *RandomGeneratorUtil::nextItem(sounds, CRandomGenerator::getDefault());
 
-	return boost::none;
+	return std::nullopt;
 }
 
-boost::optional<std::string> CGObjectInstance::getRemovalSound() const
+std::optional<std::string> CGObjectInstance::getRemovalSound() const
 {
 	const auto & sounds = VLC->objtypeh->getObjectSounds(ID, subID).removal;
 	if(!sounds.empty())
 		return *RandomGeneratorUtil::nextItem(sounds, CRandomGenerator::getDefault());
 
-	return boost::none;
+	return std::nullopt;
 }
 
 std::string CGObjectInstance::getHoverText(PlayerColor player) const
@@ -384,7 +384,7 @@ void CGObjectInstance::serializeJson(JsonSerializeFormat & handler)
 		handler.serializeInt("l", pos.z);
 		JsonNode app;
 		appearance->writeJson(app, false);
-		handler.serializeRaw("template",app, boost::none);
+		handler.serializeRaw("template", app, std::nullopt);
 	}
 
 	{

lib/mapObjects/CObjectHandler.h

@@ -171,10 +171,9 @@ public:
 
 	virtual bool isTile2Terrain() const { return false; }
 
-	boost::optional<std::string> getAmbientSound() const;
-	boost::optional<std::string> getVisitSound() const;
-	boost::optional<std::string> getRemovalSound() const;
-
+	std::optional<std::string> getAmbientSound() const;
+	std::optional<std::string> getVisitSound() const;
+	std::optional<std::string> getRemovalSound() const;
 
 	/** VIRTUAL METHODS **/
 

lib/mapObjects/CQuest.cpp

@@ -1067,7 +1067,7 @@ void CGSeerHut::serializeJsonOptions(JsonSerializeFormat & handler)
 
 			if(rawId)
 			{
-				rID = rawId.get();
+				rID = rawId.value();
 			}
 			else
 			{

lib/mapObjects/CRewardableConstructor.cpp

@@ -140,8 +140,8 @@ void CRandomRewardObjectInfo::configureReward(CRewardableObject * object, CRando
 
 	for ( auto node : source["changeCreatures"].Struct() )
 	{
-		CreatureID from (VLC->modh->identifiers.getIdentifier (node.second.meta, "creature", node.first) .get());
-		CreatureID dest (VLC->modh->identifiers.getIdentifier (node.second.meta, "creature", node.second.String()).get());
+		CreatureID from(VLC->modh->identifiers.getIdentifier(node.second.meta, "creature", node.first).value());
+		CreatureID dest(VLC->modh->identifiers.getIdentifier(node.second.meta, "creature", node.second.String()).value());
 
 		reward.extraComponents.emplace_back(Component::EComponentType::CREATURE, dest.getNum(), 0, 0);
 

lib/mapObjects/CommonConstructors.cpp

@@ -50,7 +50,7 @@ void CTownInstanceConstructor::afterLoadFinalization()
 	{
 		filters[entry.first] = LogicalExpression<BuildingID>(entry.second, [this](const JsonNode & node)
 		{
-			return BuildingID(VLC->modh->identifiers.getIdentifier("building." + faction->getJsonKey(), node.Vector()[0]).get());
+			return BuildingID(VLC->modh->identifiers.getIdentifier("building." + faction->getJsonKey(), node.Vector()[0]).value());
 		});
 	}
 }
@@ -98,7 +98,7 @@ void CHeroInstanceConstructor::afterLoadFinalization()
 	{
 		filters[entry.first] = LogicalExpression<HeroTypeID>(entry.second, [](const JsonNode & node)
 		{
-			return HeroTypeID(VLC->modh->identifiers.getIdentifier("hero", node.Vector()[0]).get());
+			return HeroTypeID(VLC->modh->identifiers.getIdentifier("hero", node.Vector()[0]).value());
 		});
 	}
 }

lib/mapObjects/JsonRandom.cpp

@@ -99,7 +99,7 @@ namespace JsonRandom
 		
 		std::string resourceName = loadKey(value, rng, defaultResources);
 		si32 resourceAmount = loadValue(value, rng, 0);
-		si32 resourceID(VLC->modh->identifiers.getIdentifier(value.meta, "resource", resourceName).get());
+		si32 resourceID(VLC->modh->identifiers.getIdentifier(value.meta, "resource", resourceName).value());
 
 		TResources ret;
 		ret[resourceID] = resourceAmount;
@@ -138,7 +138,7 @@ namespace JsonRandom
 		{
 			for(const auto & pair : value.Struct())
 			{
-				SecondarySkill id(VLC->modh->identifiers.getIdentifier(pair.second.meta, "skill", pair.first).get());
+				SecondarySkill id(VLC->modh->identifiers.getIdentifier(pair.second.meta, "skill", pair.first).value());
 				ret[id] = loadValue(pair.second, rng);
 			}
 		}
@@ -153,7 +153,7 @@ namespace JsonRandom
 			
 			for(const auto & element : value.Vector())
 			{
-				SecondarySkill id(VLC->modh->identifiers.getIdentifier(element.meta, "skill", loadKey(element, rng, defaultSkills)).get());
+				SecondarySkill id(VLC->modh->identifiers.getIdentifier(element.meta, "skill", loadKey(element, rng, defaultSkills)).value());
 				ret[id] = loadValue(element, rng);
 			}
 		}
@@ -163,7 +163,7 @@ namespace JsonRandom
 	ArtifactID loadArtifact(const JsonNode & value, CRandomGenerator & rng)
 	{
 		if (value.getType() == JsonNode::JsonType::DATA_STRING)
-			return ArtifactID(VLC->modh->identifiers.getIdentifier("artifact", value).get());
+			return ArtifactID(VLC->modh->identifiers.getIdentifier("artifact", value).value());
 
 		std::set<CArtifact::EartClass> allowedClasses;
 		std::set<ArtifactPosition> allowedPositions;
@@ -224,7 +224,7 @@ namespace JsonRandom
 	SpellID loadSpell(const JsonNode & value, CRandomGenerator & rng, std::vector<SpellID> spells)
 	{
 		if (value.getType() == JsonNode::JsonType::DATA_STRING)
-			return SpellID(VLC->modh->identifiers.getIdentifier("spell", value).get());
+			return SpellID(VLC->modh->identifiers.getIdentifier("spell", value).value());
 
 		vstd::erase_if(spells, [=](const SpellID & spell)
 		{
@@ -252,7 +252,7 @@ namespace JsonRandom
 	CStackBasicDescriptor loadCreature(const JsonNode & value, CRandomGenerator & rng)
 	{
 		CStackBasicDescriptor stack;
-		stack.type = VLC->creh->objects[VLC->modh->identifiers.getIdentifier("creature", value["type"]).get()];
+		stack.type = VLC->creh->objects[VLC->modh->identifiers.getIdentifier("creature", value["type"]).value()];
 		stack.count = loadValue(value, rng);
 		if (!value["upgradeChance"].isNull() && !stack.type->upgrades.empty())
 		{
@@ -288,7 +288,7 @@ namespace JsonRandom
 				info.minAmount = static_cast<si32>(node["min"].Float());
 				info.maxAmount = static_cast<si32>(node["max"].Float());
 			}
-			const CCreature * crea = VLC->creh->objects[VLC->modh->identifiers.getIdentifier("creature", node["type"]).get()];
+			const CCreature * crea = VLC->creh->objects[VLC->modh->identifiers.getIdentifier("creature", node["type"]).value()];
 			info.allowedCreatures.push_back(crea);
 			if (node["upgradeChance"].Float() > 0)
 			{