public interface NodeVisitor
boolean visit(AstNode node)
node - the AST node. Will never visit an AstRoot node, since
the AstRoot is where the visiting begins.true if the children should be visited. If false,
the subtree rooted at this node is skipped. The node
argument should never be null -- the individual
AstNode classes should skip any children that are not
present in the source when they invoke this method.