Package edu.harvard.seas.pl.abcdatalog.ast

Class PredicateSym

java.lang.Object

edu.harvard.seas.pl.abcdatalog.ast.PredicateSym

public class PredicateSym
extends Object

A basic predicate symbol in Datalog.

Field Summary

Fields

Modifier and Type	Field	Description
protected final int	arity	Arity of any atom formed from this predicate symbol.
protected final String	sym	Identifier of the predicate symbol (i.e.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PredicateSym(String sym, int arity)	Constructs a predicate symbol from an identifier and a non-negative arity.

Method Summary

Modifier and Type	Method	Description
static PredicateSym	create(String sym, int arity)	Returns a predicate symbol with the given string identifier and arity.
int	getArity()	Returns the arity of this predicate symbol.
String	getSym()	Returns the string identifier of this predicate symbol.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

sym

protected final String sym

Identifier of the predicate symbol (i.e. the symbol itself).

arity

protected final int arity

Arity of any atom formed from this predicate symbol.

Constructor Details

PredicateSym

protected PredicateSym(String sym,
 int arity)

Constructs a predicate symbol from an identifier and a non-negative arity.

Parameters:

sym - identifier

arity - non-negative arity

Method Details

create

public static PredicateSym create(String sym,
 int arity)

Returns a predicate symbol with the given string identifier and arity.

Parameters:

sym - the string identifier

arity - the arity

Returns:

the predicate symbol

getSym

public String getSym()

Returns the string identifier of this predicate symbol.

Returns:

the string identifier

getArity

public int getArity()

Returns the arity of this predicate symbol.

Returns:

the arity

toString

public String toString()

Overrides:

toString in class Object