anchor.diff:                  let response = yield fetch('/api/data');
                   let json = yield response.json();
                   let data = JSON.parse(json);
  -                let response2 = yield fetch(`/api/data/${data.id}`);
  +                let resp2 = yield fetch(`/api/x/${data.id}`);
                   ...
                 } catch (err) {
                   console.log(err);
  
positive.code:             }).then((json) => {
                return data = JSON.parse(json);
              }).then((data) => {
                return fetch(`/api/data/${data.id}`);
              })
              ....
              }).catch((err) => {
  
negative.code:         h1 Stage 0
          p const classes, Relationships, String.prototype.at, Structured Clone, weak references, Set/Map.prototype.toJSON, do expressions, Function Bind syntax, private object state
  
        section(data-bespoke-hash="end")
          h1 Thanks
          h3 Daniel Budden
          h3 Github: #[a(href="https://github.com/d3pis3d") d3spis3d]
          h3 Twitter: #[a(href="https://twitter.com/danlbudden") @danlbudden]
          h4 #[a(href="http://d3spis3d.github.io/es2015-deep-dive-pres") http://d3spis3d.github.io/es2015-deep-dive-pres]
  
      script(src='build/build.js')
  