In a visit expression, can the default be labeled like the cases?

Question

Example:

visit(Sometree)
{
    case a:someNodeA(_,_): HandleNodeA(a);
    default:               Handle(???);
}

So i want to handle all the other cases by using default, how can I do this?

Answer 1

visit does not support default because it needs something specific to bind while visiting. Instead you can write a pattern that matches truly everything. For example:

visit(sometree) {
   case node x : handleAllTreeLikeThings(x);
   case str y(value x, value y) : handleAllBinaryTrees(y, x, y);
   case value x : handleAllValuesWhatsoever(x);
}