1 var stream = require('stream')
4 function isStream (obj) {
5 return obj instanceof stream.Stream
9 function isReadable (obj) {
10 return isStream(obj) && typeof obj._read == 'function' && typeof obj._readableState == 'object'
14 function isWritable (obj) {
15 return isStream(obj) && typeof obj._write == 'function' && typeof obj._writableState == 'object'
19 function isDuplex (obj) {
20 return isReadable(obj) && isWritable(obj)
24 module.exports = isStream
25 module.exports.isReadable = isReadable
26 module.exports.isWritable = isWritable
27 module.exports.isDuplex = isDuplex