OrdinaryAtom Struct Reference

Stores ordinary atoms of kind p(a1, ..., an). More...

#include <include/dlvhex2/Atoms.h>

Inheritance diagram for OrdinaryAtom:

Collaboration diagram for OrdinaryAtom:

Public Member Functions
bool	unifiesWith (const OrdinaryAtom &a) const
	Checks if the atom unifies with another one.
bool	unifiesWith (const OrdinaryAtom &a, RegistryPtr reg) const
	Checks if the atom unifies with another one.
bool	existsHomomorphism (RegistryPtr reg, const OrdinaryAtom &a) const
	Checks if there is a homomorphism which maps this atom to another one.
	OrdinaryAtom (IDKind kind)
	Constructor.
	OrdinaryAtom (IDKind kind, const std::string &text)
	Constructor.
	OrdinaryAtom (IDKind kind, const std::string &text, const Tuple &tuple)
	Constructor.
std::ostream &	print (std::ostream &o) const
	Prints the atom in a human readable format.
Data Fields
std::string	text
	The textual representation of the whole thing this is stored for efficient parsing and printing.

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Detailed Description

Stores ordinary atoms of kind p(a1, ..., an).

Definition at line 95 of file Atoms.h.

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Constructor & Destructor Documentation

OrdinaryAtom::OrdinaryAtom

(

IDKind

kind

)

[inline]

Constructor.

Parameters:

kind	See Atom::kind.

Definition at line 145 of file Atoms.h.

OrdinaryAtom::OrdinaryAtom	(	IDKind	kind,
		const std::string &	text
	)		[inline]

Constructor.

Parameters:

kind	See Atom::kind.
test	See OrdinaryAtom::text.

Definition at line 153 of file Atoms.h.

OrdinaryAtom::OrdinaryAtom	(	IDKind	kind,
		const std::string &	text,
		const Tuple &	tuple
	)		[inline]

Constructor.

Parameters:

kind	See Atom::kind.
test	See OrdinaryAtom::text.
tuple	See Atom::tuple.

Definition at line 162 of file Atoms.h.

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Member Function Documentation

bool OrdinaryAtom::existsHomomorphism	(	RegistryPtr	reg,
		const OrdinaryAtom &	a
	)		const

Checks if there is a homomorphism which maps this atom to another one.

While unification allows only for replacing variables (consistently) in order to make atoms equal, a homomorphism might also substitute null values (auxiliaries of type '0', see Registry).

Parameters:

reg	Registry used to interpret atom arguments.
a	Atom to compare to.

Returns:

True if there is a homomorphism from this atom to a and false otherwise.

Definition at line 323 of file Atoms.cpp.

References DBGLOG, DBGLOG_SCOPE, printvector(), and Atom::tuple.

std::ostream& OrdinaryAtom::print

(

std::ostream &

o

)

const [inline]

Prints the atom in a human readable format.

Parameters:

o	Stream to print.

Returns:

o.

Definition at line 172 of file Atoms.h.

References printvector().

DLVHEX_NAMESPACE_BEGIN bool OrdinaryAtom::unifiesWith

(

const OrdinaryAtom &

a

)

const

Checks if the atom unifies with another one.

This variant of the method works only for atoms without function symbols.

Parameters:

a	Atom to compare to.

Returns:

True if this atom unifies with a and false otherwise.

Definition at line 54 of file Atoms.cpp.

References DBGLOG, DBGLOG_SCOPE, printvector(), and Atom::tuple.

Referenced by ComponentGraph::calculateFixedDomain(), ComponentGraph::calculateStratificationInfo(), AnnotatedGroundProgram::computeAdditionalDependencies(), Nogood::match(), InternalGrounder::matchOrdinary(), StrongSafetyChecker::operator()(), GenPluginAtom1::retrieve(), unifiesWith(), ImmediateNogoodGrounder::update(), and LazyNogoodGrounder::update().

bool OrdinaryAtom::unifiesWith	(	const OrdinaryAtom &	a,
		RegistryPtr	reg
	)		const

Checks if the atom unifies with another one.

This variant of the method works also recursively for atoms with function symbols.

Parameters:

a	Atom to compare to.
reg	Registry used to interpret atom arguments.

Returns:

True if this atom unifies with a and false otherwise.

Definition at line 132 of file Atoms.cpp.

References Term::arguments, DBGLOG, ID_FAIL(), RawPrinter::print(), Atom::tuple, and unifiesWith().

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Field Documentation

std::string OrdinaryAtom::text

The textual representation of the whole thing this is stored for efficient parsing and printing.

Note: We could make 'text' part of a template parameter of OrdinaryAtom, such that different backends can store different "efficient" representations here (e.g., we could store clasp- or dlv-library internal atom representations here and index them). If we don't need it, we can replace it by an empty struct and conserve space.

Also note: If we only need this for printing, we should generate it on-demand and save a lot of effort if not everything is printed.

Definition at line 111 of file Atoms.h.

Referenced by ExternalAtomMask::addOutputAtoms(), DependencyGraph::createAuxiliaryRuleHead(), handle_fact::operator()(), RawPrinter::print(), Registry::printAtomForUser(), RawPrinter::printWithoutPrefix(), and ExternalAtomMask::updateMask().

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The documentation for this struct was generated from the following files:

• include/dlvhex2/Atoms.h
• src/Atoms.cpp