Package jason.stdlib

Class eval

java.lang.Object

jason.asSemantics.DefaultInternalAction

jason.stdlib.eval

All Implemented Interfaces:

InternalAction, Serializable

@Manual(literal=".eval(term,query)",
        hint="evaluates the logical expression (which computes to true or false), the result is unified with term",
        argsHint={"the variable that unifies with the result of evaluation","the formula that is evaluated"},
        argsType={"variable, atoms true or false","logical formula"},
        examples={".eval(X, true | false): X unifies with true",".eval(X, 3<5 & not 4+2<3): X unifies with true"},
        seeAlso="")
public class eval
extends DefaultInternalAction

Internal action: .eval(Var,Logical Expression).

Description: evaluates the logical expression (which computes to true or false), the result is unified with Var.

Parameters:

• + term (variable, atoms true or false): the variable that unifies with the result of evaluation.
  
• + query (logical formula): the formula that is evaluated.
  

Examples:

• .eval(X, true | false): X unifies with true.
• .eval(X, 3invalid input: '<'5 invalid input: '&' not 4+2invalid input: '<'3): X unifies with true.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
eval()

Method Summary

Modifier and Type	Method	Description
protected void	checkArguments(Term[] args)
Object	execute(TransitionSystem ts, Unifier un, Term[] args)	Executes the internal action.
int	getMaxArgs()
int	getMinArgs()
Term[]	prepareArguments(Literal body, Unifier un)	Prepare body's terms to be used in 'execute', normally it consist of cloning and applying each term

Methods inherited from class jason.asSemantics.DefaultInternalAction

canBeUsedInContext, destroy, suspendIntention

Methods inherited from class java.lang.Object

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

Constructor Details

eval

public eval()

Method Details

getMinArgs

public int getMinArgs()

Overrides:

getMinArgs in class DefaultInternalAction

getMaxArgs

public int getMaxArgs()

Overrides:

getMaxArgs in class DefaultInternalAction

prepareArguments

public Term[] prepareArguments(Literal body,
 Unifier un)

Description copied from interface: InternalAction

Prepare body's terms to be used in 'execute', normally it consist of cloning and applying each term

Specified by:

prepareArguments in interface InternalAction

Overrides:

prepareArguments in class DefaultInternalAction

checkArguments

protected void checkArguments(Term[] args)
                       throws JasonException

Overrides:

checkArguments in class DefaultInternalAction

Throws:

JasonException

execute

public Object execute(TransitionSystem ts,
 Unifier un,
 Term[] args)
               throws Exception

Description copied from interface: InternalAction

Executes the internal action. It should return a Boolean or an Iterator. A true boolean return means that the IA was successfully executed. An Iterator result means that there is more than one answer for this IA (e.g. see member internal action).

Specified by:

execute in interface InternalAction

Overrides:

execute in class DefaultInternalAction

Throws:

Exception