Symbolic Atom Inspection

Detailed Description

Inspection of atoms occurring in ground logic programs.

For an example, see symbolic-atoms.c.

Typedefs
typedef struct clingo_symbolic_atoms	clingo_symbolic_atoms_t
	Object to inspect symbolic atoms in a program—the relevant Herbrand base gringo uses to instantiate programs. More...
typedef uint64_t	clingo_symbolic_atom_iterator_t
	Object to iterate over symbolic atoms. More...
typedef bool(*	clingo_symbol_callback_t) (clingo_symbol_t const *symbols, size_t symbols_size, void *data)
	Callback function to inject symbols. More...

Functions
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_size (clingo_symbolic_atoms_t const *atoms, size_t *size)
	Get the number of different atoms occurring in a logic program. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_begin (clingo_symbolic_atoms_t const *atoms, clingo_signature_t const *signature, clingo_symbolic_atom_iterator_t *iterator)
	Get a forward iterator to the beginning of the sequence of all symbolic atoms optionally restricted to a given signature. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_end (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t *iterator)
	Iterator pointing to the end of the sequence of symbolic atoms. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_find (clingo_symbolic_atoms_t const *atoms, clingo_symbol_t symbol, clingo_symbolic_atom_iterator_t *iterator)
	Find a symbolic atom given its symbolic representation. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_iterator_is_equal_to (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t a, clingo_symbolic_atom_iterator_t b, bool *equal)
	Check if two iterators point to the same element (or end of the sequence). More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_symbol (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, clingo_symbol_t *symbol)
	Get the symbolic representation of an atom. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_is_fact (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, bool *fact)
	Check whether an atom is a fact. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_is_external (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, bool *external)
	Check whether an atom is external. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_literal (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, clingo_literal_t *literal)
	Returns the (numeric) aspif literal corresponding to the given symbolic atom. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_signatures_size (clingo_symbolic_atoms_t const *atoms, size_t *size)
	Get the number of different predicate signatures used in the program. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_signatures (clingo_symbolic_atoms_t const *atoms, clingo_signature_t *signatures, size_t size)
	Get the predicate signatures occurring in a logic program. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_next (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, clingo_symbolic_atom_iterator_t *next)
	Get an iterator to the next element in the sequence of symbolic atoms. More...
CLINGO_VISIBILITY_DEFAULT bool	clingo_symbolic_atoms_is_valid (clingo_symbolic_atoms_t const *atoms, clingo_symbolic_atom_iterator_t iterator, bool *valid)
	Check whether the given iterator points to some element with the sequence of symbolic atoms or to the end of the sequence. More...

Typedef Documentation

clingo_symbol_callback_t

typedef bool(* clingo_symbol_callback_t) (clingo_symbol_t const *symbols, size_t symbols_size, void *data)

Callback function to inject symbols.

Parameters

symbols	array of symbols
symbols_size	size of the symbol array
data	user data of the callback

Returns

whether the call was successful; might set one of the following error codes:

• clingo_error_bad_alloc

See also

clingo_ground_callback_t

clingo_symbolic_atom_iterator_t

typedef uint64_t clingo_symbolic_atom_iterator_t

Object to iterate over symbolic atoms.

Such an iterator either points to a symbolic atom within a sequence of symbolic atoms or to the end of the sequence.

Note

Iterators are valid as long as the underlying sequence is not modified. Operations that can change this sequence are clingo_control_ground(), clingo_control_cleanup(), and functions that modify the underlying non-ground program.

clingo_symbolic_atoms_t

typedef struct clingo_symbolic_atoms clingo_symbolic_atoms_t

Object to inspect symbolic atoms in a program—the relevant Herbrand base gringo uses to instantiate programs.

See also

clingo_control_symbolic_atoms()

Function Documentation

clingo_symbolic_atoms_begin()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_begin	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_signature_t const *	signature,
		clingo_symbolic_atom_iterator_t *	iterator
	)

Get a forward iterator to the beginning of the sequence of all symbolic atoms optionally restricted to a given signature.

Parameters

[in]	atoms	the target
[in]	signature	optional signature
[out]	iterator	the resulting iterator

Returns

whether the call was successful

Examples:

propagator.c, and symbolic-atoms.c.

clingo_symbolic_atoms_end()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_end	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t *	iterator
	)

Iterator pointing to the end of the sequence of symbolic atoms.

Parameters

[in]	atoms	the target
[out]	iterator	the resulting iterator

Returns

whether the call was successful

Examples:

backend.c, propagator.c, and symbolic-atoms.c.

clingo_symbolic_atoms_find()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_find	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbol_t	symbol,
		clingo_symbolic_atom_iterator_t *	iterator
	)

Find a symbolic atom given its symbolic representation.

Parameters

[in]	atoms	the target
[in]	symbol	the symbol to lookup
[out]	iterator	iterator pointing to the symbolic atom or to the end of the sequence if no corresponding atom is found

Returns

whether the call was successful

Examples:

ast.c, and backend.c.

clingo_symbolic_atoms_is_external()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_is_external	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		bool *	external
	)

Check whether an atom is external.

An atom is external if it has been defined using an external directive and has not been released or defined by a rule.

Parameters

[in]	atoms	the target
[in]	iterator	iterator to the atom
[out]	external	whether the atom is a external

Returns

whether the call was successful

Examples:

symbolic-atoms.c.

clingo_symbolic_atoms_is_fact()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_is_fact	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		bool *	fact
	)

Check whether an atom is a fact.

Note

This does not determine if an atom is a cautious consequence. The grounding or solving component's simplifications can only detect this in some cases.

Parameters

[in]	atoms	the target
[in]	iterator	iterator to the atom
[out]	fact	whether the atom is a fact

Returns

whether the call was successful

Examples:

symbolic-atoms.c.

clingo_symbolic_atoms_is_valid()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_is_valid	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		bool *	valid
	)

Check whether the given iterator points to some element with the sequence of symbolic atoms or to the end of the sequence.

Parameters

[in]	atoms	the target
[in]	iterator	the iterator
[out]	valid	whether the iterator points to some element within the sequence

Returns

whether the call was successful

clingo_symbolic_atoms_iterator_is_equal_to()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_iterator_is_equal_to	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	a,
		clingo_symbolic_atom_iterator_t	b,
		bool *	equal
	)

Check if two iterators point to the same element (or end of the sequence).

Parameters

[in]	atoms	the target
[in]	a	the first iterator
[in]	b	the second iterator
[out]	equal	whether the two iterators are equal

Returns

whether the call was successful

Examples:

backend.c, propagator.c, and symbolic-atoms.c.

clingo_symbolic_atoms_literal()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_literal	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		clingo_literal_t *	literal
	)

Returns the (numeric) aspif literal corresponding to the given symbolic atom.

Such a literal can be mapped to a solver literal (see the Theory Propagation module) or be used in rules in aspif format (see the Program Building module).

Parameters

[in]	atoms	the target
[in]	iterator	iterator to the atom
[out]	literal	the associated literal

Returns

whether the call was successful

Examples:

ast.c, backend.c, and propagator.c.

clingo_symbolic_atoms_next()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_next	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		clingo_symbolic_atom_iterator_t *	next
	)

Get an iterator to the next element in the sequence of symbolic atoms.

Parameters

[in]	atoms	the target
[in]	iterator	the current iterator
[out]	next	the succeeding iterator

Returns

whether the call was successful

Examples:

propagator.c, and symbolic-atoms.c.

clingo_symbolic_atoms_signatures()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_signatures	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_signature_t *	signatures,
		size_t	size
	)

Get the predicate signatures occurring in a logic program.

Parameters

[in]	atoms	the target
[out]	signatures	the resulting signatures
[in]	size	the number of signatures

Returns

whether the call was successful; might set one of the following error codes:

• clingo_error_bad_alloc
• clingo_error_runtime if the size is too small

See also

clingo_symbolic_atoms_signatures_size()

clingo_symbolic_atoms_signatures_size()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_signatures_size	(	clingo_symbolic_atoms_t const *	atoms,
		size_t *	size
	)

Get the number of different predicate signatures used in the program.

Parameters

[in]	atoms	the target
[out]	size	the number of signatures

Returns

whether the call was successful

clingo_symbolic_atoms_size()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_size	(	clingo_symbolic_atoms_t const *	atoms,
		size_t *	size
	)

Get the number of different atoms occurring in a logic program.

Parameters

[in]	atoms	the target
[out]	size	the number of atoms

Returns

whether the call was successful

clingo_symbolic_atoms_symbol()

CLINGO_VISIBILITY_DEFAULT bool clingo_symbolic_atoms_symbol	(	clingo_symbolic_atoms_t const *	atoms,
		clingo_symbolic_atom_iterator_t	iterator,
		clingo_symbol_t *	symbol
	)

Get the symbolic representation of an atom.

Parameters

[in]	atoms	the target
[in]	iterator	iterator to the atom
[out]	symbol	the resulting symbol

Returns

whether the call was successful

Examples:

propagator.c, and symbolic-atoms.c.