visitStack method
Implementation
@override
String visitStack(StackNode node) {
final base = visit(node.base);
final above = node.above != null ? visit(node.above!) : null;
final below = node.below != null ? visit(node.below!) : null;
final buffer = StringBuffer(base);
if (above != null) buffer.write(" with $above above");
if (below != null) buffer.write(" with $below below");
return buffer.toString();
}