diff --git a/alib2data/src/automaton/FSM/DFA.h b/alib2data/src/automaton/FSM/DFA.h index ffb889aa43b4dedbd2568cc4b1f212082a32ab7e..b31b2350ed711f7422a709bf3d6bb4a8fe7656db 100644 --- a/alib2data/src/automaton/FSM/DFA.h +++ b/alib2data/src/automaton/FSM/DFA.h @@ -1,6 +1,22 @@ /* * DFA.h * + * This file is part of Algorithms library toolkit. + * Copyright (C) 2017 Jan Travnicek (jan.travnicek@fit.cvut.cz) + + * Algorithms library toolkit is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + + * Algorithms library toolkit is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + + * You should have received a copy of the GNU General Public License + * along with Algorithms library toolkit. If not, see <http://www.gnu.org/licenses/>. + * * Created on: Mar 25, 2013 * Author: Jan Travnicek */ @@ -28,8 +44,22 @@ namespace automaton { /** - * Represents Finite Automaton. - * Can store nondeterministic finite automaton without epsilon transitions. + * \brief + * Deterministic finite automaton. Accepts regular languages. + + * \details + * Definition is classical definition of finite automata. + * A = (Q, T, I, \delta), + * Q (States) = nonempty finite set of states, + * T (TerminalAlphabet) = finite set of terminal symbols - having this empty won't let automaton do much though, + * \delta = transition function of the form A \times a -> B, where A, B \in Q and a \in T, + * I (InitialState) = initial state, + * + * Note that target state of a transition is required. + * This class is used to store minimal, total, ... variants of deterministic finite automata. + * + * \tparam SymbolType used for the terminal alphabet + * \tparam StateType used to the states, and the initial state of the automaton. */ class InputAlphabet; class States; @@ -38,146 +68,339 @@ class InitialState; template<class SymbolType, class StateType > class DFA final : public AutomatonBase, public alib::Components < DFA < SymbolType, StateType >, SymbolType, ext::tuple < InputAlphabet >, ext::tuple < >, StateType, ext::tuple < States, FinalStates >, ext::tuple < InitialState > > { -protected: + /** + * Transition function as mapping from a state times an input symbol on the left hand side to a state. + */ ext::map < ext::pair < StateType, SymbolType >, StateType > transitions; public: + /** + * \brief Creates a new instance of Deterministic finite automaton with a concrete initial state. + * + * \param initialState the initial state of the automaton + */ explicit DFA ( StateType initialState ); + + /** + * \brief Creates a new instance of Deterministic finite automaton with a concrete set of states, input alphabet, initial state, and a set of final states. + * + * \param states the initial set of states of the automaton + * \param inputAlphabet the initial input alphabet + * \param initialState the initial state of the automaton + * \param finalStates the initial set of final states of the automaton + */ explicit DFA ( ext::set < StateType > states, ext::set < SymbolType > inputAlphabet, StateType initialState, ext::set < StateType > finalStates ); - virtual AutomatonBase * clone ( ) const; + /** + * @copydoc automaton::AutomatonBase::clone() + */ + virtual AutomatonBase * clone ( ) const override; - virtual AutomatonBase * plunder ( ) &&; + /** + * @copydoc automaton::AutomatonBase::plunder() + */ + virtual AutomatonBase * plunder ( ) && override; + /** + * Getter of the initial state. + * + * \returns the initial state of the automaton + */ const StateType & getInitialState ( ) const { return this-> template accessElement < InitialState > ( ).get ( ); } + /** + * Setter of the initial state. + * + * \param state new initial state of the automaton + * + * \returns true if the initial state was indeed changed + */ bool setInitialState ( StateType state ) { return this-> template accessElement < InitialState > ( ).set ( std::move ( state ) ); } + /** + * Getter of states. + * + * \returns the states of the automaton + */ const ext::set < StateType > & getStates ( ) const { return this-> template accessComponent < States > ( ).get ( ); } + /** + * Adder of a state. + * + * \param state the new state to be added to a set of states + * + * \returns true if the state was indeed added + */ bool addState ( StateType state ) { return this-> template accessComponent < States > ( ).add ( std::move ( state ) ); } + /** + * Setter of states. + * + * \param states completely new set of states + */ void setStates ( ext::set < StateType > states ) { this-> template accessComponent < States > ( ).set ( std::move ( states ) ); } + /** + * Remover of a state. + * + * \param state a state to be removed from a set of states + * + * \returns true if the state was indeed removed + */ void removeState ( const StateType & state ) { this-> template accessComponent < States > ( ).remove ( state ); } + /** + * Getter of final states. + * + * \returns the final states of the automaton + */ const ext::set < StateType > & getFinalStates ( ) const { return this-> template accessComponent < FinalStates > ( ).get ( ); } + /** + * Adder of a final state. + * + * \param state the new state to be added to a set of final states + * + * \returns true if the state was indeed added + */ bool addFinalState ( StateType state ) { return this-> template accessComponent < FinalStates > ( ).add ( std::move ( state ) ); } + /** + * Setter of final states. + * + * \param states completely new set of final states + */ void setFinalStates ( ext::set < StateType > states ) { this-> template accessComponent < FinalStates > ( ).set ( std::move ( states ) ); } + /** + * Remover of a final state. + * + * \param state a state to be removed from a set of final states + * + * \returns true if the state was indeed removed + */ void removeFinalState ( const StateType & state ) { this-> template accessComponent < FinalStates > ( ).remove ( state ); } + /** + * Getter of the input alphabet. + * + * \returns the input alphabet of the automaton + */ const ext::set < SymbolType > & getInputAlphabet ( ) const { return this-> template accessComponent < InputAlphabet > ( ).get ( ); } + /** + * Adder of a input symbol. + * + * \param symbol the new symbol to be added to an input alphabet + * + * \returns true if the symbol was indeed added + */ bool addInputSymbol ( SymbolType symbol ) { return this-> template accessComponent < InputAlphabet > ( ).add ( std::move ( symbol ) ); } + /** + * Adder of input symbols. + * + * \param symbols new symbols to be added to an input alphabet + */ void addInputSymbols ( ext::set < SymbolType > symbols ) { this-> template accessComponent < InputAlphabet > ( ).add ( std::move ( symbols ) ); } + /** + * Setter of input alphabet. + * + * \param symbols completely new input alphabet + */ void setInputAlphabet ( ext::set < SymbolType > symbols ) { this-> template accessComponent < InputAlphabet > ( ).set ( std::move ( symbols ) ); } + /** + * Remover of an input symbol. + * + * \param symbol a symbol to be removed from an input alphabet + * + * \returns true if the symbol was indeed removed + */ void removeInputSymbol ( const SymbolType & symbol ) { this-> template accessComponent < InputAlphabet > ( ).remove ( symbol ); } /** - * Adds transition defined by parameters to the automaton. - * @param current current state - * @param input input symbol - * @param next next state - * @throws AutomatonException when transition already exists or when transition contains state or symbol not present in the automaton + * \brief Add a transition to the automaton. + * + * \details The transition is in a form A times a -> B, where A, B \in Q and a \in T + * + * \param current the source state (A) + * \param input the input symbol (a) + * \param next the target state (B) + * + * \throws AutomatonException when transition contains state or symbol not present in the automaton components + * + * \returns true if the transition was indeed added */ bool addTransition ( StateType current, SymbolType input, const StateType next ); /** - * Removes transition from the automaton. - * @param transition transition to remove - * @throws AutomatonException when transition doesn't exists. + * \brief Removes a transition from the automaton. + * + * \details The transition is in a form A times a -> B, where A, B \in Q and a \in T + * + * \param current the source state (A) + * \param input the input symbol (a) + * \param next the target state (B) + * + * \returns true if the transition was indeed removed */ bool removeTransition ( const StateType & current, const SymbolType & input, const StateType & next ); /** - * @return automaton transitions + * Get the transition function of the automaton in its natural form. + * + * \returns transition function of the automaton */ const ext::map < ext::pair < StateType, SymbolType >, StateType > & getTransitions ( ) const; /** - * @return automaton transitions from state + * Get the transition function of the automaton, with the source state fixed as a view to the internal representation. + * + * \param from filter the transition function based on this state as a source state + * + * \returns section of a transition function of the automaton with the source state fixed */ ext::range < typename ext::map < ext::pair < StateType, SymbolType >, StateType >::const_iterator > getTransitionsFromState ( const StateType & from ) const; /** - * @return automaton transitions to state + * Get the transition function of the automaton, with the target state fixed in the transitions natural representation. + * + * \param to filter the transition function based on this state as a source state + * + * \returns section of a transition function of the automaton with the target state fixed */ - ext::map < ext::pair < StateType, SymbolType >, StateType > getTransitionsToState ( const StateType & from ) const; + ext::map < ext::pair < StateType, SymbolType >, StateType > getTransitionsToState ( const StateType & to ) const; /** - * Determines whether DFA is total deterministic - * FA is deterministic if and only if - * \li \c it is deterministic. (Trivial here) - * \li \c size of transition function \forall states and \forall input symbols \delta (from state, input symbol) = 1 - * @return true when automaton is total deterministic, false otherwise + * \brief Determines whether Deterministic finite automaton is total + * + * Deterministic finite automaton is total if and only if + * \li \c size of transition function \forall states \times input symbols = 1 + * + * \return true if the automaton is total, false otherwise */ bool isTotal ( ) const; - virtual int compare ( const ObjectBase & other ) const { + /** + * @copydoc alib::CommonBase<ObjectBase>::compare ( const ObjectBase & ) + */ + virtual int compare ( const ObjectBase & other ) const override { if ( ext::type_index ( typeid ( * this ) ) == ext::type_index ( typeid ( other ) ) ) return this->compare ( ( decltype ( * this ) )other ); return ext::type_index ( typeid ( * this ) ) - ext::type_index ( typeid ( other ) ); } - virtual int compare ( const DFA & other ) const; + /** + * The actual compare method + * + * \param other the other instance + * + * \returns the actual relation between two by type same automata instances + */ + int compare ( const DFA & other ) const; - virtual void operator >>( std::ostream & os ) const; + /** + * @copydoc alib::CommonBase<ObjectBase>::operator >> ( std::ostream & ) + */ + virtual void operator >>( std::ostream & os ) const override; - virtual explicit operator std::string ( ) const; + /** + * @copydoc alib::CommonBase<ObjectBase>::operator std::string ( ) + */ + virtual explicit operator std::string ( ) const override; + /** + * \brief The XML tag name of class. + * + * \details Intentionaly a static member function to be safe in the initialisation before the main function starts. + * + * \returns string representing the XML tag name of the class + */ static const std::string & getXmlTagName() { static std::string xmlTagName = "DFA"; return xmlTagName; } + /** + * Parsing from a sequence of xml tokens helper. + * + * \params input the iterator to sequence of xml tokens to parse from + * + * \returns the new instance of the automaton + */ static DFA parse ( ext::deque < sax::Token >::iterator & input ); + + /** + * Helper for parsing of individual transitions of the automaton from a sequence of xml tokens. + * + * \params input the iterator to sequence of xml tokens to parse from + * \params automaton the automaton to add the rule to + */ static void parseTransition ( ext::deque < sax::Token >::iterator & input, DFA & automaton ); - void compose ( ext::deque < sax::Token > & out ) const; + /** + * Composing to a sequence of xml tokens helper. + * + * \param out the sink for new xml tokens representing the automaton + */ + virtual void compose ( ext::deque < sax::Token > & out ) const override; + + /** + * Helper for composing transitions of the automaton to a sequence of xml tokens. + * + * \param out the sink for xml tokens representing the rules of the automaton + */ void composeTransitions ( ext::deque < sax::Token > & out ) const; - virtual alib::ObjectBase * inc ( ) &&; + /** + * @copydoc alib::GrammarBase::inc() + */ + virtual alib::ObjectBase * inc ( ) && override; + /** + * Type of normalized automaton. + */ typedef DFA < > normalized_type; - virtual AutomatonBase * normalize ( ) && { + /** + * Helper for normalisation of types specified by templates used as internal datatypes of symbols and states. + * + * \returns new instance of the automaton with default template parameters or unmodified instance if the template parameters were already the default ones + */ + virtual AutomatonBase * normalize ( ) && override { if ( typeid ( DFA < > ) == typeid ( DFA < SymbolType, StateType > ) ) return this; @@ -415,9 +638,23 @@ alib::ObjectBase* DFA < SymbolType, StateType >::inc() && { namespace alib { +/** + * Helper class specifying constraints for the automaton's internal input alphabet component. + * + * \tparam SymbolType used for the terminal alphabet of the automaton. + * \tparam StateType used for the terminal alphabet of the automaton. + */ template<class SymbolType, class StateType > class ComponentConstraint< automaton::DFA<SymbolType, StateType>, SymbolType, automaton::InputAlphabet > { public: + /** + * Returns true if the symbol is still used in some transition of the automaton. + * + * \param automaton the tested automaton + * \param symbol the tested symbol + * + * \returns true if the symbol is used, false othervise + */ static bool used ( const automaton::DFA<SymbolType, StateType> & automaton, const SymbolType & symbol ) { for ( const std::pair < const ext::pair < StateType, SymbolType >, StateType > & transition : automaton.getTransitions ( ) ) if ( transition.first.second == symbol ) @@ -426,18 +663,46 @@ public: return false; } + /** + * Returns true as all symbols are possibly available to be elements of the input alphabet. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true + */ static bool available ( const automaton::DFA<SymbolType, StateType> &, const SymbolType & ) { return true; } + /** + * All symbols are valid as input symbols. + * + * \param automaton the tested automaton + * \param state the tested state + */ static void valid ( const automaton::DFA<SymbolType, StateType> &, const SymbolType & ) { } }; +/** + * Helper class specifying constraints for the automaton's internal states component. + * + * \tparam SymbolType used for the terminal alphabet of the automaton. + * \tparam StateType used for the terminal alphabet of the automaton. + */ template<class SymbolType, class StateType > class ComponentConstraint< automaton::DFA<SymbolType, StateType>, StateType, automaton::States > { public: + /** + * Returns true if the state is still used in some transition of the automaton. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true if the state is used, false othervise + */ static bool used ( const automaton::DFA<SymbolType, StateType> & automaton, const StateType & state ) { if ( automaton.getInitialState ( ) == state ) return true; @@ -452,38 +717,100 @@ public: return false; } + /** + * Returns true as all states are possibly available to be elements of the states. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true + */ static bool available ( const automaton::DFA<SymbolType, StateType> &, const StateType & ) { return true; } + /** + * All states are valid as a state of the automaton. + * + * \param automaton the tested automaton + * \param state the tested state + */ static void valid ( const automaton::DFA<SymbolType, StateType> &, const StateType & ) { } }; +/** + * Helper class specifying constraints for the automaton's internal final states component. + * + * \tparam SymbolType used for the terminal alphabet of the automaton. + * \tparam StateType used for the terminal alphabet of the automaton. + */ template<class SymbolType, class StateType > class ComponentConstraint< automaton::DFA<SymbolType, StateType>, StateType, automaton::FinalStates > { public: + /** + * Returns true if the state is still used in some transition of the automaton. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true if the state is used, false othervise + */ static bool used ( const automaton::DFA<SymbolType, StateType> &, const StateType & ) { return false; } + /** + * Determines whether the state is available in the automaton's states set. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true if the state is already in the set of states of the automaton + */ static bool available ( const automaton::DFA<SymbolType, StateType> & automaton, const StateType & state ) { return automaton.getStates ( ).count ( state ); } + /** + * All states are valid as a final state of the automaton. + * + * \param automaton the tested automaton + * \param state the tested state + */ static void valid ( const automaton::DFA<SymbolType, StateType> &, const StateType & ) { } }; +/** + * Helper class specifying constraints for the automaton's internal initial state element. + * + * \tparam SymbolType used for the terminal alphabet of the automaton. + * \tparam StateType used for the terminal alphabet of the automaton. + */ template<class SymbolType, class StateType > class ElementConstraint< automaton::DFA<SymbolType, StateType>, StateType, automaton::InitialState > { public: + /** + * Determines whether the state is available in the automaton's states set. + * + * \param automaton the tested automaton + * \param state the tested state + * + * \returns true if the state is already in the set of states of the automaton + */ static bool available ( const automaton::DFA<SymbolType, StateType> & automaton, const StateType & state ) { return automaton.getStates ( ).count ( state ); } + /** + * All states are valid as an initial state of the automaton. + * + * \param automaton the tested automaton + * \param state the tested state + */ static void valid ( const automaton::DFA<SymbolType, StateType> &, const StateType & ) { }