playing around with auto-filtered/mapped `can.List`

gistfile1.js

function test() {
  var sourceList = new can.List();
  var stream = sourceList.filteredStream(function(todo, map) {
    if (!todo.attr("done")) {
      todo.attr("steps").forEach(map);
    }
  });
  var targetList = stream.toList();

  sourceList.push({
    done: false,
    description: "Do the Bitovi Dance",
    steps: ["hop around", "do a little twirl"]
  });
  console.log(targetList.attr()); // ["hop around", "do a little twirl"]

  sourceList.push({
    done: true,
    description: "Assert opinion",
    steps: ["clear throat", "push up glasses", "raise index finger", "mansplain"]
  });
  console.log(targetList.attr()); // ["hop around", "do a little twirl"]

  sourceList.push({
    done: false,
    description: "Do some open source",
    steps: ["Download Emacs.app", "grow a neckbeard", "make a PR on github"]
  });
  console.log(targetList.attr()); // ["hop around", "do a little twirl", "Download Emacs.app", "grow a neckbeard", "make a PR on github"]

  sourceList.attr(0).attr("steps").pop();
  console.log(targetList.attr()); // ["hop around", "Download Emacs.app", "grow a neckbeard", "make a PR on github"]

  sourceList.attr(0).attr("done", true);
  console.log(targetList.attr()); // ["Download Emacs.app", "grow a neckbeard", "make a PR on github"]

  sourceList.shift();
  console.log(targetList.attr()); // ["Download Emacs.app", "grow a neckbeard", "make a PR on github"]

  sourceList.shift();
  console.log(targetList.attr()); // ["Download Emacs.app", "grow a neckbeard", "make a PR on github"]

  sourceList.shift();
  console.log(targetList.attr()); // []
  
  console.log("Benchmarking...");
  console.time("building");
  for (var i = 0; i < 100; i++) {
    sourceList.push({
      done: false,
      description: "Do the Bitovi Dance",
      steps: ["hop around", "do a little twirl"]
    });
  }
  console.timeEnd("building");
  console.log("target list length: ", targetList.length);
  console.time("done");
  sourceList.forEach(function(todo) { todo.attr("done", true); });
  console.timeEnd("done");
  console.time("todo");
  sourceList.forEach(function(todo) { todo.attr("done", false); });
  console.timeEnd("todo");
  console.time("removing");
  for (var i = 0; i < sourceList.length; i++) {
    sourceList.pop();
  }
  console.timeEnd("removing");
}
test();