nest-stream

nest-stream

Stream that allows nesting another stream for each value of the outer stream and streams the flattened result.

'use strict';

var nestStream = require('nest-stream')
  , through = require('through')
  , from = require('from');

var stream = nestStream(getInnerStream);

function getInnerStream (outerVal) {
  return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
}

function stringify (data) {
  this.queue(data + ' ');
}

from([10, 20, 30, 40])
  .pipe(stream)
  .pipe(through(stringify))
  .on('end', function () { console.error('ended') })
  .pipe(process.stdout);

// => 11 13 14 15  21 23 24 25  31 33 34 35  41 43 44 45  ended

more examples

Installation

npm install nest-stream

API

nestStream(getInnerStream[, sep])

/**
 * Streams values resulting from all the inner streams generated from the values of the outer stream.
 * 
 * @name exports
 * @function
 * @param getInnerStream {Function} function (outerValue) { .. } that returns a stream generated from the provided value
 * @param sep {Object} (optional) 
 *  any non-null object to serve as a separator between values queued for one value piped by the outer stream
 *  default: ''
 * @return {Stream} that queues a value for each value provided by either of the inner streams
 */

License

MIT