未捕获的TypeError：无法在d3.v3.min.js中读取未定义的属性'prelim'：4

Question

我正在尝试实现像这样的可折叠树：http://bl.ocks.org/mbostock/4339083。

我在AJAX中加载数据并得到正确的响应，如下所示：

{
    "id": 17,
    "id_ts": "Keyword60",
    "value": "april",
    "children": [
        {
            "id": 5,
            "id_ts": "Keyword96",
            "value": "[0-9]{1,4}",
            "children": []
        }
    ]
} 

但我错了：

  

未捕获的TypeError：无法读取未定义的属性'prelim'

我不明白我的错误将参数传递给D3

           d3.select("#map").html("");
                var m = [20, 120, 20, 120],
                w = 1195 - m[1] - m[3],
                h = 700 - m[0] - m[2],
                i = 0,
                root;

                var tree = d3.layout.tree()
                    .size([h, w]);
                //d3.json("/symfony/web/assets/json/" + source, function(json) {
                var diagonal = d3.svg.diagonal()
                    .projection(function(d) { return [d.y, d.x]; });

                var vis = d3.select("#map").append("svg:svg")
                    .attr("width", w + m[1] + m[3])
                    .attr("height", h + m[0] + m[2])
                    .append("svg:g")
                    .attr("transform", "translate(" + m[3] + "," + m[0] + ")");
                root = data;
                root.x0 = h / 2;
                root.y0 = 0;

                function toggleAll(d) {
                  if (d.children) {
                    d.children.forEach(toggleAll);
                    toggle(d);
                  }
                }

                // Initialize the display to show a few nodes.
                update(root);

                function update(source) {
                    var duration = d3.event && d3.event.altKey ? 5000 : 500;

                    // Compute the new tree layout.
                    var nodes = tree.nodes(source).reverse();
                    console.log(nodes);
                    // Normalize for fixed-depth.
                    nodes.forEach(function(d) { d.y = d.depth * 180; });

                    // Update the nodes…
                    var node = vis.selectAll("g.node")
                        .data(nodes, function(d) { return d.id || (d.id = ++i); });

                    // Enter any new nodes at the parent's previous position.
                    var nodeEnter = node.enter().append("svg:g")
                        .attr("class", "node")
                        .attr("transform", function(d) { return "translate(" + source.y0 + "," + source.x0 + ")"; })
                        .on("click", function(d) { toggle(d); update(d); detail(d); });

                    nodeEnter.append("svg:circle")
                        .attr("r", 1e-6)
                        .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; });

                    nodeEnter.append("svg:text")
                        .attr("x", function(d) { return d.children || d._children ? -10 : 10; })
                        .attr("dy", ".35em")
                        .attr("text-anchor", function(d) { return d.children || d._children ? "end" : "start"; })
                        .text(function(d) { return d.value; })
                        .style("fill-opacity", 1e-6);

                    // Transition nodes to their new position.
                    var nodeUpdate = node.transition()
                        .duration(duration)
                        .attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; });

                    nodeUpdate.select("circle")
                        .attr("r", 4.5)
                        .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; });

                    nodeUpdate.select("text")
                        .style("fill-opacity", 1);

                    // Transition exiting nodes to the parent's new position.
                    var nodeExit = node.exit().transition()
                        .duration(duration)
                        .attr("transform", function(d) { return "translate(" + source.y + "," + source.x + ")"; })
                        .remove();

                    nodeExit.select("circle")
                        .attr("r", 1e-6);

                    nodeExit.select("text")
                        .style("fill-opacity", 1e-6);

                    // Update the links…
                    var link = vis.selectAll("path.link")
                        .data(tree.links(nodes), function(d) { return d.target.id; });

                    // Enter any new links at the parent's previous position.
                    link.enter().insert("svg:path", "g")
                        .attr("class", "link")
                        .attr("d", function(d) {
                          var o = {x: source.x0, y: source.y0};
                          return diagonal({source: o, target: o});
                        })
                      .transition()
                        .duration(duration)
                        .attr("d", diagonal);

                    // Transition links to their new position.
                    link.transition()
                        .duration(duration)
                        .attr("d", diagonal);

                    // Transition exiting nodes to the parent's new position.
                    link.exit().transition()
                        .duration(duration)
                        .attr("d", function(d) {
                          var o = {x: source.x, y: source.y};
                          return diagonal({source: o, target: o});
                        })
                        .remove();

                    // Stash the old positions for transition.
                    nodes.forEach(function(d) {
                      d.x0 = d.x;
                      d.y0 = d.y;
                    });
                }

                // Toggle children.
                function toggle(d) {
                  if (d.children) {
                    d._children = d.children;
                    d.children = null;
                  } else {
                    d.children = d._children;
                    d._children = null;
                  }
                }