public function testVisitExpressionTreeOfOneLeaf()
{
$expression = ExpressionSymbol::createAdapterForTerminal('a');
$eliminator = new Visitor();
$eliminator->visitExpression($expression);
$actual = $eliminator->getRoot();
$this->assertEquals($expression, $actual);
}
/**
* @param Expression $e
*
* @return Expression|null
*/
public function getDepthFirstWalkResult(Expression $e)
{
$visitor = new Visitor();
$hierarchicVisitDispatcher = new CompleteVisitDispatcher($visitor);
$walker = new DepthFirstStackBasedWalker();
$walker->walk($e, $hierarchicVisitDispatcher);
$walkResult = $visitor->getRoot();
return $walkResult;
}
/**
* @param Production $production
* @return array|Production[]
*/
public function transform(Production $production)
{
$expression = $production->getExpression();
$visitor = new Visitor();
$hierarchicVisitDispatcher = new CompleteVisitDispatcher($visitor);
$walker = new DepthFirstStackBasedWalker();
$walker->walk($expression, $hierarchicVisitDispatcher);
$rootExpression = $visitor->getRoot();
$production = new StandardProduction($production->getNonTerminal(), $rootExpression);
return array($production);
}
