Function getKeyFromID

test/react.js:1403–1405

(id)

  // Use non-numeric keys to prevent V8 performance issues:
  // https://github.com/facebook/react/pull/7232
  var getKeyFromID = function (id) {
    return '.' + id;
  };
  var getIDFromKey = function (key) {
    return parseInt(key.substr(1), 10);
  };