1  var inherits              = require('util').inherits
 2    , Readable              = require('stream').Readable
 3    , ReadableAsyncKit      = require('./lib/readable_asynckit.js')
 4    , ReadableParallel      = require('./lib/readable_parallel.js')
 5    , ReadableSerial        = require('./lib/readable_serial.js')
 6    , ReadableSerialOrdered = require('./lib/readable_serial_ordered.js')
 7    ;
 8  
 9  // API
10  module.exports =
11  {
12    parallel      : ReadableParallel,
13    serial        : ReadableSerial,
14    serialOrdered : ReadableSerialOrdered, 
15  };
16  
17  inherits(ReadableAsyncKit, Readable);
18  
19  inherits(ReadableParallel, ReadableAsyncKit);
20  inherits(ReadableSerial, ReadableAsyncKit);
21  inherits(ReadableSerialOrdered, ReadableAsyncKit);