tom.library.sl
Class Choice

java.lang.Object
  tom.library.sl.AbstractStrategy
      tom.library.sl.AbstractStrategyCombinator
          tom.library.sl.Choice

All Implemented Interfaces:

Strategy, Visitable

public class Choice
extends AbstractStrategyCombinator

Choice(v1,v2) = v1 if v1 succeeds

Choice(v1,v2) = v2 if v1 fails

Visitor combinator with two arguments, that tries to apply the first argument and if it fails tries the other (left-biased choice).

Note that any side-effects of v1 are not undone when it fails.

Field Summary

static int	FIRST
static int	THEN

Fields inherited from class tom.library.sl.AbstractStrategyCombinator

arguments

Fields inherited from class tom.library.sl.AbstractStrategy

environment

Method Summary

static Strategy	make(Strategy first, Strategy then)
int	visit(Introspector introspector) Visit the current subject (found in the environment) and place its result in the environment.
<T> T	visitLight(T subject, Introspector introspector) Visit the subject any in a light way (without environment)

Methods inherited from class tom.library.sl.AbstractStrategyCombinator

getChildAt, getChildCount, getChildren, getVisitor, getVisitors, initSubterm, initSubterm, initSubterm, initSubterm, initSubterm, setChildAt, setChildren

Methods inherited from class tom.library.sl.AbstractStrategy

getAncestor, getEnvironment, getPosition, getRoot, getSubject, init, init, setEnvironment, setRoot, setSubject, visit, visit, visit, visit, visitLight

Methods inherited from class java.lang.Object

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

Field Detail

FIRST

public static final int FIRST

See Also:

Constant Field Values

THEN

public static final int THEN

See Also:

Constant Field Values

Method Detail

make

public static Strategy make(Strategy first,
                            Strategy then)

visitLight

public <T> T visitLight(T subject,
                        Introspector introspector)
             throws VisitFailure

Description copied from interface: Strategy

Visit the subject any in a light way (without environment)

Parameters:

subject - the subject to visit.

Throws:

VisitFailure - in case of failure.

visit

public int visit(Introspector introspector)

Description copied from interface: Strategy

Visit the current subject (found in the environment) and place its result in the environment. Sets the environment flag to Environment.FAILURE in case of failure

Parameters:

introspector - the introspector