let Master = require('mapreducejs/master');
let Agent = require('mapreducejs/agent');

let Master = require('mapreducejs/master');
// Supply an socket.io instance
let master = new Master(io);

...
// Connect to agent
// Returns a promise that resolves when finished connecting.
master.connect(socket);

let dataset = master.source([...]);

dataset.map((entry) => {
  return ...
}).then((result) => {
  ...
});

dataset.reduce((prev, next) => {
  return ...
}).then((result) => {
  ...
});

dataset.map((entry) => {
  // Map
  return ...
}).then((result) => {
  // Reduce
  result.reduce((prev, next) => {
    return ...
  }).then((result) => {
    // Map
    result.map((entry) => {
      return ...
    }).then((result) => {
      let { data } = result;
    });
  });
});

let Agent = require('mapreducejs/agent');
// or <script src="agent.min.js"></script>
let agent = new Agent();

...
// Connect to master
// Supply an socket.io instance
// Returns a promise that resolves when finished connecting.
agent.connect(socket);