io.github.prolobjectlink.prolog

Interface PrologVariable

All Superinterfaces:

Comparable<PrologTerm>, PrologElement, PrologTerm

public interface PrologVariable
extends PrologTerm

Prolog term that represent variable data type. Prolog variables are created using PrologProvider.newVariable(int) for anonymous variables and PrologProvider.newVariable(String, int) for named variables. The Prolog variables can be used and reused because they remain in java heap. You can instantiate a prolog variable and used it any times in the same clause because refer to same variable every time.

 
 PrologVariable x = provider.newVariable("X");
 PrologVariable y = provider.newVariable("Y");
 PrologVariable z = provider.newVariable("Z");
 engine.assertz(provider.newStructure(grandparent, x, z), provider.newStructure(parent, x, y),
                provider.newStructure(parent, y, z));
 
 

Since:

1.0

Author:

Jose Zalacain

Method Summary

Modifier and Type	Method and Description
String	getName() Name that identify this variable
int	getPosition() Non negative integer that represent the variable position of the Structure where the variable is first time declared.
boolean	isAnonymous() Check that current variable be an anonymous variable
void	setName(String name) Set the name for current prolog variable term.

Methods inherited from interface io.github.prolobjectlink.prolog.PrologTerm

cast, getArgument, getArguments, getArity, getFunctor, getIndicator, getObject, getProvider, getTerm, getType, hasIndicator, isAtom, isAtomic, isClass, isCompound, isDouble, isEmptyList, isEntry, isEvaluable, isFalseType, isField, isFloat, isInteger, isList, isLong, isMap, isMixin, isNil, isNullType, isNumber, isObjectType, isParameter, isReference, isResult, isStructure, isTrueType, isVariable, isVariableBound, isVariableNotBound, isVoidType, match, unify

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface io.github.prolobjectlink.prolog.PrologElement

isClause, isTerm

Method Detail

isAnonymous

boolean isAnonymous()

Check that current variable be an anonymous variable

Returns:

- true if the current variable is an anonymous variable, false in other case

Since:

1.0

getName

String getName()

Name that identify this variable

Returns:

variable name

Since:

1.0

setName

void setName(String name)

Set the name for current prolog variable term. If the under-laying prolog variable term don't have rename option, a new under-laying variable is created with the given name.

Parameters:

name - name to be set to the current variable.

Since:

1.0

getPosition

int getPosition()

Non negative integer that represent the variable position of the Structure where the variable is first time declared.

Returns:

the variable position

Since:

1.0