snewcomer

const getBooleanTable = number => Array(Math.pow(2, number))
  .fill()
  .map((_, idx) => idx)
  .map(num => num.toString(2).padStart(number, '0'))
  .map(stringOfBits =>
    stringOfBits.split('').map(bit => Boolean(parseInt(bit)))
  )

console.log(getBooleanTable(3))

snewcomer

DOM Event Order

• Events execution order is not guaranteed based on the heirarchy of the DOM when using window.addEventListener. Instead window.addEventListener will run listeners in the order they are registered.
• DOM3 specifies events flow down the DOM tree and then back up. addEventListener's are called on the way back up, but can be called as evt propogates down the tree with true for the useCapture argument.

Ideas

Taking control of event listeners for the user limits a lot of the flexibility the DOM + JS provides. See this issue for an example.

Basically, we have not covered bubbling and cancellation DOM Events with LiveView.

snewcomer

The microtask queue is useful for allowing the current browser task to finish while pushing some logic to happen immediately after that task (or next task).

• "click" event with non trivial, expensive logic. To allow the browser to finish that event, return sync control to that task while throwing the resulting logic in a queueMicrotask callback.
• async rendering

snewcomer

def flatten(list), do: flatten(list, []) |> Enum.reverse
def flatten([h | t], acc) when h == [], do: flatten(t, acc)
def flatten([h | t], acc) when is_list(h), do: flatten(t, flatten(h, acc))
def flatten([h | t], acc), do: flatten(t, [h | acc])
def flatten([], acc), do: acc

snewcomer

import Ember from 'ember';

export default Ember.Component.extend({
  classNames: ['red']
});

snewcomer

  def join_project(%Project{} = project, %User{} = me) do
    project = Repo.preload(project, :users)
    users =
      project.users ++ [me]
      |> Enum.map(&Ecto.Changeset.change/1)

    event
    |> change_project()
    |> put_assoc(:users, users)
    |> Repo.update()

snewcomer

function indexTree(root) {
  var treeWalker = document.createTreeWalker(
      root,
      NodeFilter.SHOW_ELEMENT);

  var el;
  while((el = treeWalker.nextNode())) {
      var key = getNodeKey(el);
      if (key) {
          fromNodesLookup[key] = el;

snewcomer

const removeMatchingLine = (str, match) => {
  let index = str.indexOf(match);
  // If it is not found, return str
  if (index === -1) {
    return str;
  }

  // Look for the previous line feed
  let start = index;
  while(str.charAt(start) !== "\n") {

snewcomer

import Ember from 'ember';

/**
 * example data structure
 *
 * persistentContainer: {
 *   tickets: Map.{
 *     id: Obj,
 *     id: Obj
 *   },

snewcomer

defmodule Easydiagonal do

  def diagonal(n, p) do
    {sum, _acc} = build_triangle(n, p)
    sum
  end

  defp build_triangle(n, p) do
    # [[1], [1, 1], [1, 2, 1], [1, 3, 3, 1], [1, 4, 6, 4, 1], ...]  
    Stream.iterate({0, [1]}, fn {sum, last} ->