tree-walker

Generic recursive tree walker

Usage

    var walker = new TreeWalker(function (node, next) {
        console.log("Enter " + node.id);
        next(TreeWalker.CONTINUE);
    }, function (node, next) {
        console.log("Leave" + node.id);
        next(TreeWalker.ABORT); //Only the first node in the tree
    });
 
    return walker.walk(tree).then(function () {
        console.log("Done");
    });

The TreeWalker constructor accepts 3 arguments:

• enterNode: function(node, next)
  • node: The node that is being visited
  • next: function(visitresult): Callback that should be invoked to move onto the next node. You may provide an optional visitresult.
• leaveNode: function(node, next)
  • node: The node that is being visited
  • next: function(visitresult): Callback that should be invoked to move onto the next node. You may provide an optional visitresult.
• getChildren: function(node)
  • node: The node to obtain the children of.

Visit results

enterNode and leaveNode can both return a result to the caller, the following values are possible:

TreeWalker.ABORT

Applicable to both enterNode and leaveNode, it will abort the walk of the tree from the current position

TreeWalker.CONTINUE

Applicable to both enterNode and leaveNodethe walk of the tree will be continued, this is equivalent to returning nothing.

TreeWalker.SKIPCHILDREN

Applicable only to enterNode. it will signal the walker to skip the children of the current node.

TreeWalker.SKIPSIBLINGS

Applicable to both enterNode and leaveNode, it signal the walker to skip the siblings of the current node.