initial commit with forEach, modify, get, paths, nodes

traverse.js

@@ -0,0 +1,73 @@
+exports.Traverse = Traverse;
+function Traverse (obj) {
+    if (!(this instanceof Traverse)) return new Traverse(obj);
+
+    this.get = function () { return obj };
+
+    this.modify = function (f) {
+        var path = [];
+        var parents = [];
+        walk(obj);
+        return this;
+
+        function walk (node) {
+            var state = {
+                node : node,
+                path : [].concat(path),
+                parent : parents.slice(-1)[0],
+                key : path.slice(-1)[0],
+                isRoot : node == obj,
+                notRoot : node != obj,
+                isLeaf : typeof(node) != 'object'
+                    || Object.keys(node).length == 0,
+                notLeaf : typeof(node) == 'object'
+                    && Object.keys(node).length > 0,
+                update : function (x) {
+                    if (state.isRoot) {
+                        obj = x;
+                    }
+                    else {
+                        state.parent.node[state.key] = x;
+                    }
+                    state.node = x;
+                },
+                level : path.length,
+            };
+
+            f.call(state, node);
+            if (typeof(state.node) == 'object') {
+                parents.push(state);
+                Object.keys(state.node).forEach(function (key) {
+                    path.push(key);
+                    walk(state.node[key]);
+                    path.pop();
+                });
+                parents.pop();
+            }
+        }
+    };
+
+    this.forEach = function (f) {
+        this.modify(function (node) {
+            delete this.update;
+            f.call(this,node);
+        },null);
+        return this;
+    };
+
+    this.paths = function () {
+        var acc = [];
+        this.each(function (x) {
+            acc.push(this.path); 
+        });
+        return acc;
+    };
+
+    this.nodes = function () {
+        var acc = [];
+        this.each(function (x) {
+            acc.push(this.node);
+        });
+        return acc;
+    };
+}