Chryus

import React from "react";
import fetchData from "./fetchData";

export default function permitList(props) {
  const data = fetchData("https://data.cityofchicago.org/resource/ydr8-5enu.json?");
  return (
    <div>
      <ul>
        {data.map(el => (
          <li key={el.id}>{el.permit_type}</li>

Chryus

// fetchData.js
import { useState, useEffect } from "react";

export default function fetchData(url) {
  const [data, setData] = useState([]);

  useEffect(() => {
    fetch(url)
      .then(response => response.json())
      .then(data => setData(data));

Chryus

<DataFetcher
  render={data => {
    return (
      <div>
        <ul>
          {data.map(el => (
            <li key={el.id}>{el.title}</li>
          ))}
        </ul>
      </div>

Chryus

import React, { Component } from "react";

export default class DataFetcher extends Component {
  state = { data: [] };

  componentDidMount() {
    fetch("https://data.cityofchicago.org/resource/ydr8-5enu.json?")
      .then(response => response.json())
      .then(data =>
        this.setState(() => {

Chryus

// dataFetcher.js
import { useState, useEffect } from "react";

export default function dataFetcher(url) {
  const [data, setData] = useState([]);

  useEffect(() => {
    fetch(url)
      .then(response => response.json())
      .then(data => setData(data));

Chryus

# graffiti.rb
class Graffiti < ActiveRecord::Base
  belongs_to :artist, class_name: "User"
  has_many :uploads
  has_many :comments
  has_many :upvotes, as: :upvotable
end

# upload.rb
class Upload < ApplicationRecord

Chryus

class User < ActiveRecord::Base  
  # ...
  
  has_many :upvotes
  has_many :graffiti, through: :upvotes, source: :upvotable, source_type: "Graffiti"
  has_many :uploads, through: :upvotes, source: :upvotable, source_type: "Upload"
  
  # ...
end

Chryus

# graffiti.rb
class Graffiti < ActiveRecord::Base
  has_many :uploads
  has_many :upvotes, as: :upvotable
end

# upload.rb
class Upload < ApplicationRecord
  belongs_to :user
  belongs_to :graffiti

Chryus

# user.rb
class User < ActiveRecord::Base 
  has_many :upvotes
  has_many :graffiti, through: :upvotes
end

# graffiti.rb
class Graffiti < ActiveRecord::Base 
  has_many :upvotes
  has_many :users, through: :upvotes

Chryus

// In the initial code, I wasn't aware that let would create a new binding for 
// each variable inside my loop. I assumed a closure around the setTimeout function
// was necessary to create new copy of the variables at each step.
animate() {
  let previousDelay = 0;
  let styles = null;
  for (let sequence of this.dataSet) {
    let delay = sequence[0] + previousDelay;
    let objects = sequence.filter(this.isObject);
    styles = this.formatStyles(objects);