text: var flow = require('../index').flow;
  var as = require('../index').as;
  var fs = require('fs');
  
  var myFlow = flow('myFlow')(
    function readFiles(file1, file2) {
      fs.readFile(file1, 'utf8', this.async(as(1)));
      fs.readFile(file2, 'utf8', this.async(as(1)));
    },
    function concat(data1, data2) {
      this.next(data1 + data2);
    },
    function end(data) {
      if (this.err) throw this.err;
      console.log(data);
      console.log('done');
      this.next();
    }
  );
  
  myFlow('file1', 'file2');