cache array.find on long list example

gistfile1.txt

const nodes = [
  { id:"abc", content:"Lorem ipsum"},
  { id:"def", content:"Dolor sit" },
  // ...
];

const keyedNodes = {}

const getNode = id => {
  if (!keyedNodes[id]) {
    keyedNodes[id] = nodes.find(n => n.id === id);
  }

  return keyedNodes[id];
}

console.log(getNode('abc'));
// => { id:"abc", content:"Lorem ipsum" }

console.log(getNode('abc'));
// This time we are coming from keyedNodes!
// => { id:"abc", content:"Lorem ipsum" }