Namespace mata::nft::builder

namespace builder

Namespace providing options to build NFAs.

Typedefs

using NameStateMap = std::unordered_map<std::string, State>

Functions

Nft create_single_word_nft(const Word &word)

Create an automaton accepting only a single word.

Nft create_single_word_nft(const WordName &word, Alphabet *alphabet = nullptr)

Create an automaton accepting only a single word.

Parameters:

  • word – Word to accept.

  • alphabet – Alphabet to use in NFA for translating word into symbols. If specified, the alphabet has to contain translations for all the word symbols. If left empty, a new alphabet with only the symbols of the word will be created.

Nft create_empty_string_nft(size_t num_of_levels = DEFAULT_NUM_OF_LEVELS)

Create automaton accepting only epsilon string.

Nft create_sigma_star_nft(size_t num_of_levels = DEFAULT_NUM_OF_LEVELS)

Create automaton accepting sigma star over the passed alphabet using DONT_CARE symbol.

Parameters:

num_of_levels – [in] Number of levels in the created NFT.

Nft create_sigma_star_nft(const Alphabet *alphabet = new OnTheFlyAlphabet{}, size_t num_of_levels = DEFAULT_NUM_OF_LEVELS)

Create automaton accepting sigma star over the passed alphabet.

Parameters:

  • alphabet – [in] Alphabet to construct sigma star automaton with. When alphabet is left empty, the default empty alphabet is used, creating an automaton accepting only the empty string.

  • num_of_levels – [in] Number of levels in the created NFT.

Nft construct(const parser::ParsedSection &parsec, Alphabet *alphabet, NameStateMap *state_map = nullptr)

Loads an automaton from Parsed object.

Nft construct(const IntermediateAut &inter_aut, Alphabet *alphabet, NameStateMap *state_map = nullptr)

Loads an automaton from Parsed object.

void construct(Nft *result, const IntermediateAut &inter_aut, Alphabet *alphabet, NameStateMap *state_map = nullptr)

Loads an automaton from Parsed object; version for python binding.

template<class ParsedObject>
Nft construct(const ParsedObject &parsed, Alphabet *alphabet = nullptr, NameStateMap *state_map = nullptr)
Nft parse_from_mata(std::istream &nft_stream)

Parse NFA from the mata format in an input stream.

Parameters:

nft_stream – Input stream containing NFA in mata format.

Throws:

std::runtime_error – Parsing of NFA fails.

Nft parse_from_mata(const std::string &nft_in_mata)

Parse NFA from the mata format in a string.

Parameters:

nft_in_mata – String containing NFA in mata format.

Throws:

std::runtime_error – Parsing of NFA fails.

Nft parse_from_mata(const std::filesystem::path &nft_file)

Parse NFA from the mata format in a file.

Parameters:

nft_file – Path to the file containing NFA in mata format.

Throws:

  • std::runtime_error – nft_file does not exist.

  • std::runtime_error – Parsing of NFA fails.

Nft from_nfa_with_levels_zero(const nfa::Nfa &nfa, size_t num_of_levels = DEFAULT_NUM_OF_LEVELS, bool explicit_transitions = true, std::optional<Symbol> next_levels_symbol = {})

Create Nft from nfa with specified num_of_levels.

This function takes transition from nfa as transitions between zero level and the first level of NFT. All transition between the remaining levels are created based on the function parameters: explicit_transitions and next_levels_symbol.

Parameters:

  • nfa – NFA to create NFT from.

  • num_of_levels – Number of levels of NFT.

  • explicit_transitions – If true, the transitions between levels are explicit (i.e., no jump transitions, except for the epsilon transitions over all levels).)

  • next_levels_symbol – If specified, it is used as a symbol on transitions after the first level. If not specified, the symbol of the transition is reused.

Returns:

NFT representing nfa with num_of_levels number of levels.

Nft from_nfa_with_levels_advancing(mata::nfa::Nfa nfa, size_t num_of_levels)

Creates Nft from nfa with specified num_of_levels automatically.

It assumes that nfa is a representation of an nft without jump transitions. It assign to each state the level based on the distance from the initial state. For example, if there are 2 levels, the initial states are level 0, the successor states are level 1, the states after that level 0, etc.

If you only have one level, then it is more efficient to call the constructor that takes Nfa as input.

Throws:

std::runtime_error – if some state should be assigned two different levels or if the final state is not at level 0.